Sr. Telemaster + PicoPilot

[workshop]

UAVers,

My name is Jeff Parisse and I own a special effects company in Southern California. We've started a small special project to explore autonomous GPS navigation for a variety of reasons and I'd like to share our results and experiences here.

First some photos showing the guts. GPS58 has six test flights to mechanically trim flight surfaces and balance and next week we will take her out to the dry lakebeds for some PICOPILOT testing.

I'll post specs and details over the next few days... I look forward to sharing with and learning from you guys.

Jeff W. Parisse
www.teslacoil.com

[kd7ost]

Thanks for the pics Jeff,

Is that the GPS unit velcro'd to the wall in the first picture?
And the Telemaster must be Electric powered with those big electrical connectors is that right?

Dan

[workshop]

Dan,

Yes, that is a Garmin GSP18-LVC but it is shown in it's storage position. Normally the Garmin unit gets attached to the top center of the wing.

The GPS58 is electric. I'll have a full spec sheet probably today. So far, I get about 30 minutes in the air. I can parallel another pack for twice the time.

Here's another round of photos:

Jeff

[workshop]

PICOPILOT Test this Tuesday...

[icebear]

That's a beautiful ship Jeff! Nice arrangement of the electronics too!

Looking forward to seeing the specs and reports on the test Tuesday!

/Bjorn

[workshop]

Wow Icebear... Thank you very much...

Today's Flight Test 7 went off fine. WP32 return mode works. The new prop and motor battery give better performance (don't know the trade-off yet) and the extra weight of the RF shielded enclosure and NiMH batteries (I was using switching PSs) didn't affect flight as far as I could tell. Tomorrow the vast Southern California desert!! :D

Specs:
Airframe: Senior Telemaster (Hobby Lobby)
Wing Span: 93"
Wing Area: 1330 sq."
AUW w/o Camera: 200.6 oz.
Wing Loading: 21.7 oz./sq.'

Motor: AXI 4130/16
Prop: 16" x 10" APC-E
Battery: TP4200 6s2p
ESC: Jeti 77-O

Receiver: JR 770s (SPCM) Ch. 58
GPS Receiver: Garmin GPS18LVC
Autopilot: PICOPILOT NAV2, ALTE
Rudder Gyro: GWS PG-03
5v PS: 1450mAh, 4 Cell, NiMH
6v PS: 1650mAh, 5 Cell, NiMH
Servos: HS-645MG
Switch Harness: DPDT (both batteries at once)

Jeff Parisse
www.teslacoil.com

[icebear]

Jeff,

Thanks - it'll be interesting to hear how your desert trip goes!
I couldn't do more testing today due to the weather, AND I have a problem getting my FMS receiver to Enable/Disable the unit, so I'm looking at more tests later in the week around my local corn field..

/Icebear

[workshop]

UAVers,

The first autopilot test got off to a slow start when my wife surprised me with news of my daughter's eye doctor appointment (I had to take her). So much for dawn patrol! My friend Nick and I didn't get to the lakebed until noon (read: hot and windy).

The "neat" news was that "someone" was testing what looked like a Predator RQ-1L (might be smaller, might have fixed gear). We could watch the entire flight path including the runway flybys at 5 feet off the deck. Two chase planes (one a single engine Beechcraft of some sort) followed with one in close pursuit and one high up for bird's eye observation. They followed the UAV in probably a ten-mile oval pattern for HOURS. The uncool part was the altitude; well below the FAA's 500' (El Mirage is a State of California Public Recreational Area). The UAV team was not flying out of the Aldelanto Airstrip but a private facility about two miles NW. The buildings seemed too "commercial" to be a part of (near by) Edwards Air Force Base so I guess it is a private test strip. None-the-less, skimming a public playa with a military UAV (a killer BTW) isn't cool. Fortunately, they seemed to alter their flight plan to a much higher northern route when they saw us setting up. I'm sure they have some sort of FAA waiver but how is that going to help when they suck up some kids foamie?

My test seemed anticlimactic after all that! I programmed the Waypoint route into the plane and my handheld (Garmin eTrex Vista). We positioned the plane at altitude and engaged the autopilot. All seemed to work except the ALTE gain (50%) is too high as the plane pitched up and down (more so during turns). The wind made this a tough test to gauge the flight characteristics so we made a hotel reservation in Aldelanto for Wednesday so we can REALLY do dawn patrol on Thursday morning.

Anybody have any PICOPILOT setting suggestions other than that which can be found on their FAQ?

Jeff Parisse
www.teslacoil.com

[kd7ost]

I use the Alt3 E myself. I have the rate gain set pretty low. I have a slight amount of upthrust in my engine so keeping full throttle on won't keep me at altitude with my current gain setting. It will still rise slowly. I have GPS and video overlay system so I can watch the altitude. I have my whole system set up so that at crusing speed, (throttle setting) the Pico Alt will keep me where I set it at. For personal preference, I have my platform set to climb slightly under full power.

I would note those issues in your own plane. If you set the throttle at 50 percent or so, trim it to fly straight and level, then advance to full throttle, does the plane go up or come down or stay level? If all of that is working for you to stay level, then enable the unit and watch what happens. If the plane notably porpoises, you have too much gain. By the same token, if it won't hold it at altitude when going down wind, (sinks) or going upwind (rises), you need a little more gain. It's a balance. Easy to get when winds are calm. High winds will allow the plane to rise and sink in a bigger altitude window. It will likely take a few sessions in different winds for you to dial it in the best for you.

Dan

[workshop]

Dan,

Thanks for the input. Getting a starting point or other such advice from the PICOPILOT manufacturer always resulted in the same advice: read the FAQ. I'm so glad to be on this fourm with you folks and gettin' some work done (before I have to go back to work). :rolleyes:

Given today's prevailing winds, a Waypoint survey by car and your comments, I'm going to set-up an up-wind zig-zag pattern for Thursday's test. That way the wind direction will be simetricall for both left and right turns. Today's Figure 8 pattern was programmed offsite (in LA) and was "askew" to the wind when we got there (El Mirage Dry Lake).

Jeff

[Mike Freas]

Good luck tomorrow morning. It looks like your testing right around where I use to live(Ridgecrest).

[workshop]

UAVers,

First the Predator. It WAS flying from Adelanto Airstrip and probably was the Minuteman Project practicing landing approaches. Luckily they weren’t flying today (at 7:00am).

Nick and I got to Liberty Point on the Playa at 7:00am and setup. We were in the air a few minutes later ready to test waypoint sequencing. I wanted to observe a turn close up so I made the SECOND waypoint above our position. I, however, programmed the first waypoint almost a mile away. The lakebed looked so much smaller on the computer screen. :rolleyes: Even in real life, the illusion of distance is pretty strong. Bottom line: As the plane flew away from us and towards the first waypoint, it seemed like it was NEVER gonna turn. Even though Nick was watching the plane with binoculars, the distance was too far for me to see well so I aborted the autopilot thinking it had over flown the spot and was headed for Las Vegas.

The two flights did give us the chance to dial down the pots and get better turns but we ran out of time and juice before we could load up another set of points. Instead we erased all and tested the auto return feature. It worked great and the pitch problem is resolved. We logged about 22 minutes of airtime.

What we learned: When testing, make the FIRST waypoint close to the observer so one can observer "autopilot on" when the plane veers towards the observer/pilot. Then one can observe "autopilot sequencing on" as the plane moves on to the second waypoint. I'll make my route legs much shorter too (maybe 1/2 mile each?).

Dumb Mistake: I forgot to turn off the rudder gyro for the last two days of testing. The rudder might have been fighting the autopilot during turns. I'll set gain to zero for the next round of flight-testing.

Jeff
www.teslacoil.com

[icebear]

Thanks for the update Jeff! Interesting to read about your testing. I totally agree about setting up the waypoints closer when testing. I had the same issue when testing my first UAV last year. The waypoints where so far away that I "chickened out" fearing that I would loose radio range when my 42" Super Impress turned into a small speck just 1/2 mile away. My longes routes are only about 1.5 miles but the plane is never more than 1/2 mil away.
With my new bigger airfame (SuperMiss, 54")
I'll be more daring. Hopefully I'll be able to test it with the Geko 201 and PDC-10 this weekend!

/Icebear

[workshop]

UAVers,

Here is a link to the Google Sat. Photo of El Mirage Dry lake bed.

http://maps.google.com/?ll=34.637728,-117.59491&spn=0.067087,0.109692&t=k&om=1

Nick took photos of yesterday's test and I'll add them to this post later today...

Jeff

[lvspark]

I look forward to seeing them .. Cool Project!

[workshop]

Good luck this weekend Bjorn... It'd be interesting to hear how it goes...
Thanks LVSPARK, it's been fun so far...

San Pedro Flight Tests
Now that the NAV2 and ALTE gains are adjusted for smooth flight and reasonable turns, I'm going to bring the testing closer to home (three hour trips, three dollar gas and hotel rooms were adding up) and fly at a large soccer complex in San Pedro.

Flight Fifteen
Today I learned that it's probably a good idea to walk the (flight testing) perimeter with a handheld GPS to mark the route and landmarks in Mapsource before proceeding with programming waypoints. It seemed that the waypoints I programmed in the night before didn't correlate with the actual field and I couldn’t seem to enter the pattern. Once I walked the whole field complex (making notes of landmarks) and loaded the "bread crumb" route into Mapsource, I could much more clearly see where I needed to fly and where I had made my mistakes. The handheld GSP has become essential tool.

I've set a figure eight pattern with the waypoints at least 500 feet from each other. The turns are all equal to or greater than 90 degrees. I hope the PicoPilot has enough resolution to make this route or I'll have to go back to the desert. :o

Jeff

[kd7ost]

Sounds pretty cool Jeff. You're making some great headway. If your plane can't make the turn it might be more of a factor of aircraft speed and turn rate ability. Your rudder gain needs to be dialed down so the plane won't zig zag and it sounds like you've done that well. If you ask it to turn too sharply it's like trying to turn a 90 degree turn in a boat. It will side skid (slip) as it comes around. If your next point is inside the crafts ability to turn you will overshoot. But wait, there's more.

The Pico Pilot Nav unit uses waypoint departure sequencing which is much better in a small UAV than waypoint arrival sequencing. The "way point made" in the pico pilot sequencing software happens once the unit is within .1 mile of a waypoint. .1 mile is equal to 528 feet. In other words, If you approach a waypoint, once you are within 528 feet, the waypoint will be made good as far as the sequencer. But, it now looks for departure. As the plane travels past the waypoint the distance begins to increase. That's what the sequencer sees to tell it to now start navigating to the next waypoint. You might be 500 feet off to the right or the left of that waypoint if you have a cross wind for example. It will look like your plane didn't make the waypoint to the gnats hiney. It didn't. But it made the waypoint as far as the software goes. This needs to be like that. The small amount of error in a GPS position fix, coupled with aircraft flight dynamics and winds might have you flying around a waypoint till fuel runs out if the spec were too tight. If you had to get within a foot, the plane might skid around up there forever and never make the waypoint. Parameters in the code have to be big enough to allow small light planes to fly a course. The smaller the course gets, coupled with the bigger and faster the plane becomes, the more you can expect to see what might look like erratic behavior when flying a small course.

The plane makes one waypoint and starts to turn to the next. The first one might look pretty good. The plane starts its turn and winds or over correction can cause the plane to turn too little or too much. It starts to correct the other way. These are subtle and look fine from your ground position. Just a little way into the turn though, it’s already made the next waypoint as far as range because it’s only 500 feet away and the sequencer made it at .1 mile. You might not go right to the waypoint. It might skirt the edge of that round range target and begin to gain greater distance. This tells the sequencer to go to the next waypoint. It cranks over to cross your figure eight and your thinking, man it didn’t even come close to that second waypoint. You might think it missed but it made it and moved on already. This isn’t always going to happen the same way in such a short and tight turning course. How you enter the course in autonomous mode (bearing and range) can cause the turns to be a little different each time.

Here's an old thread where Icebear and I hammered out a learning curve on the pico pilot. Much of the information would be important to you in your route sizing application. Anyhow, it’s just something to be aware of. Icebears original unit used arrival sequencing which made his look really like it was failing when it wasn’t. The plane in the early version would start the turn as soon as it got within .1 mile. He had a course smaller than that range so it was sequencing through the course without really getting away from him. The current Pico Pilot variants use the departure sequencing like I described so it is better. If it doesn’t look good to you during flight, it might be better to run an oval course with a few in between waypoints to allow the turns to be gentler. That will allow you to evaluate the operation without over steering the plane in a tight course. A slow little plane will stay tighter than a bigger fast plane. Keeping your aircraft speed down to just enough to keep moving along will also help it not overshoot.

http://www.rcgroups.com/forums/showthread.php?t=410349

Dan

Edited to include,

Post 29 and 30 in that thread talk about the distance to waypoint issue.

[icebear]

Interesting read Jeff and Dan - and I am looking forward to the next flight report.

In the meantime I managed only one testflight of the Supermiss this weekend due to strong winds. I am planning to test the PDC-10 + Geko 201, first "return home" and the a short route.

Unfortunately, when the winds calmed down sunday evening and I finally could walk to my nearby field (I am lucky to have one really close), the FMA co-pilot wasn't correctly setup. The plane behaved well but when engaging the Co-pilot I had set the gains to low and it would loose height and enter a shallow spin. Now everything is re-calibrated and ready to go this evening. We have 75 degrees F and calm winds!

Here's a small picture of the route.

/Icebear

[workshop]

Dan,

Thank you so much for taking the time to describe waypoint sequencing to me. I have a much clearer picture in my head on how PICOPILOT works and now I can see the how the map and plane relate.

MAPSOURCE was planting a visual image of a straight-line path. That's the way the route looks on the screen. :rolleyes: Given your post and the dialogue with Icebear, I can see now that instead of a line, I should think of a 500' wide swath (representing the margin of error) with the plane overshooting the WP before "looking" for the next one. I should also slow down.

Here's a before and after of the next test I have planned for today...

Thanks again...

Jeff

[libelulamodelos]

i got also a telemaster , now our team are developing a "TERRACO", pictures soon at:
http://andresherreracali.blogspot.com

[kd7ost]

Dan,

Thank you so much for taking the time to describe waypoint sequencing to me. I have a much clearer picture in my head on how PICOPILOT works and now I can see the how the map and plane relate.

MAPSOURCE was planting a visual image of a straight-line path. That's the way the route looks on the screen. :rolleyes: Given your post and the dialogue with Icebear, I can see now that instead of a line, I should think of a 500' wide swath (representing the margin of error) with the plane overshooting the WP before "looking" for the next one. I should also slow down.

Here's a before and after of the next test I have planned for today...

Thanks again...

Jeff



Happy to throw .02 into the fray Jeff,

Here's an example of what I've seen in flight based on similar courses. I used your second picture and painted three different examples of possibilities. The first one has the skinny line. That's meant to simulate a small slow plane or a big course. Maybe 1 mile legs or something like that. In my painting I used the big red dot to simulate where the plane is at when you enable the autonomous mode. The red line through the course simulates a fair assessment of where the plane might actually track.

The second picture shows a small course and a big fast plane. It gets started from the same location but you can see it has trouble making point 2. Once it gets into range where it's makes the waypoint and starts to move farther away, it sequences on to point 3.

The third example is meant to be the same small course big plane combination as in picture 2. In this case you enter it on a course line that connects point 1 and 2. The fast speed and short distance causes the plane to overshoot point three. The sequencer see;s it came close enough and sends it on to the final point where it will start to loiter.

This was just done to illustrate possible types of examples you might see in a small course. Good work putting up that picture. One thing I've noticed is you can generally see the plane starting to crank around pretty quick in proximity of the waypoint when you have tight corners to fly. That pretty well gives you the visual clue's that keep you outside the comfort zone (at first) but well within the human panic zone. :D You'll probably keep you're eye's on it, not blinking, ready to take it back at a moments notice.

These are just examples of what it might look like. Variations in size of course, size and speed of plane, throwing in cross winds etc all play into it and will make your actual flight track unique.

Dan

[typicalaimster]

Oh neat. So it flys a route much like I saw in post 198 in this thread (http://www.rcgroups.com/forums/showthread.php?t=484568&page=14&pp=15)...

[kd7ost]

Hey that's it Scott. Even your RC car did it. I think it stayed tighter than a plane would have though.

Hows the search for the new flying field going for you guys?

Dan

[twinturbostang]

He's invaded DCRC up in my neck of the woods. It's ok though. It's hard to be in people's way with a dead servo. :D ;) ;)

[typicalaimster]

It's like you said the car DOES have a tigher turning radius than the plane will.

Well the field search here in VA is going nowhere fast. However over the river in Germantown, MD there is another club that I've been flying at. While I was there I was invited over to another electric only club in Rockville, MD. Both are about a 30-45 minute drive. However they are pretty cool with developing technologies.

I'll have a new thread up in a month or two with a new plane. About that time I'll start some new tests.

[workshop]

Dan,

I see where this is all heading (no pun intended) and that is the ability to "let go" and allow the plane do what the plane is designed to do; fly without me. I may have to go back to El Mirage and try again while tracking the plane via car.

Attached, is what I envisioned at the local park. I still plan on giving it a try at slow speed on a clear day (we were socked in today).

Jeff

[typicalaimster]

Did you have a pair of wireless serial modems? It is possible to 'snoop' the GPS's serial output and send that back to the ground. From there you could monitor on a moving map. In fact I believe that U-Nav used to sell a Y-Cable that would interface with the system and allow such a setup. They also sold their own OEM version of the Maxstreams.

I found myself adding more Waypoints with the car to keep me on track. If the waypoints were not tightly stacked together the car would wiggle its way to the next waypoint. With a plane you won't have such a tight turning radius. Your results should be a bit different. I spent a week trying to get a smooth track.

[workshop]

I plan on adding a 1 watt 900 MHz video transmitter in the future and overlay GSP data in the screen. Not as fancy as the moving map but our telemetry focus is on video. I was also thinking of placing my handheld GPS on board and d/ling the "Track" into MAPSOURCE. Again, not real time (read: fancy)...

My wife and I lived on 18th and Wyoming and later Tacoma Park and Silver Spring. I used to remember nothing but open space but I have heard things have changed... :eek: I think your traffic is worse than ours and I'm in LA! :cool:

Jeff

[icebear]

Thanks for the update and interesting to see Dan's projections! This is a great thread...

In the meantime I managed to get my Supermiss in the air yesterday and I tested the Geko + PDC-10 for the first time. Yesterday evening was perfect with 70F, clear skies with just a light breeze.

Stabilization with the Co-pilot is now fixed and I tested both "return home" and to follow a short route (purple).

It turned out that I probably had too little "gain" on the PDC-10 beacuse the plane made very large slow turns and you could actually see the Copilot stabilizing to counteract bankning and making the plane "skid" in the turns.

I made a copy of the track recorded by the Geko (black) and you can see the plane trying to turn slowly. It probably made the end waypoint while trying to navigate my track (purple) and just started circling.
Interesting also to see that the plane had a fairly constant 50 km/h (30 mph) speed with a top speed of 90 km/h (60 mph) in a dive (flying manually). And my field is at 6 m's (24 feet) above MSL.

Jeff - I guess your Telemaster would easily be able to lift a small handheld GPS if you want to 'record' how it performs while navigating your WP's.

I have now dialed in some more gain (from 25% to 50%) and I will make a new test tonight if the weather permits.

Good luck Jeff!

/Icebear

[workshop]

UAV'ers,

Man, what a morning. I left the computer, chargers and gear and took the GPS-58 to San Pedro to see if could fly the pattern shown in a previous post. Success! :D

I was able to fly the .75-mile route three times in 5:13, 5:09 and 6:13 minutes respectively including takeoffs and landings. The UAV managed to hit all points and loiter above home after each flight. It is twelve hours later and I am still grinning ear to ear. Two club buddies were there to make it even more fun! :)

The UAV oscillated a bit in pitch and roll but as I slowed down, the symptoms improved. I won't change the PICOPILOT gains until I have more airtime. I used 3.835Ah in 16 minutes at an average 65% throttle setting drawing 14.38A (25W/lb. - 83% motor efficiency). With these (preliminary) numbers, I am going to keep my course length to 2 miles or less untill I add more batteries. $$$ :mad:

Next Up: Tomorrow, I will attempt a more complicated course (as shown) and later this week I will make an attachment point on the UAV for my hand held GPS so I can download the actual track generated by the UAV and overlay it on the map and compare it to the programmed route. Neat!

Future: I am starting to look into video systems and 900MHz looks like the TX frequency I want (nope, I won't be bringing the GPS-58 to Europe with me). Does anyone have a compelling reason to go for a 2.4GHz TX?...

Jeff

[icebear]

...to a successful mission! Good work!

I had some success yesterday as I managed to get the "return home" to work after adjusting my gain on the PDC-10 from 25% to 50%!
As expected 50% was on the high side as the plane turned quite sharply and had trouble maintaining height in the turns even if it worked. 35%-40% seems to be just right..

The dreaded "smart-routing" of the Geko 201 GPS made the plane going directly to my end-point so it didn't follow the route :(
I have made a new simpler route (more spread out) which I will try this evening, but after that I will probably go back to the Picopilot!

U-NAV also informed me that they are working on an updated Editor which will work with the newer Mapsource files.

Looking forward to seeing how the GPS track will be compared to your new route Jeff!

/Bjorn

[workshop]

Re: U-NAV

That's great to hear that they are going to update their editor. Funny, however, that they are going to fix it after:

1: You and I already fixed it. :rolleyes:

2: They told me: "All of our engineering resources are currently tied up on another project so I do not anticipate allocating any time to the PICOPILOT project for the foreseeable future. From the reports we have received from PICOPILOT customers, most of them use the direct edit method of programming anyway". :rolleyes:

I wonder if they'll just write up our fix (DAxxx Naming Convention) and post it and say they fixed the problem.

The PICOPILOT seems like a fine product even if support is... uneven... :mad:

Jeff

[icebear]

I was surprised by the reply too, but since I have quickly grown tired of the re-naming procedure, I am happy they decided tofix it! Let's hope it's not only our 'quick-fix' :)
No flying today since I had to go to Switzerland in my job :(... Get's in the way sometimes, doesn't it?
/Bjorn

[workshop]

Bjorn,
I was in Switzerland on business a couple of months ago (Technorama) and it wasn't that bad. :D

Nick says that this is a great hobby for us married guys (he saw the ring in your photo) because now instead of retreating to the garage with our computers and airplanes, we can drive out to fields far away!...

Testing:
Today we flew the route described in the last post (10 waypoints, 1.1 mile route) and GPS-58 hit every one of them. We flew the route twice in about 6 minutes each. I need to slow down even more but the Telemaster just seems like it just hangs in the air.

Nick took video and if I can get my editor to work, I'll post one of the flights.

Jeff

[powerblimp]

hello where do you go in switzerland?
i just recive one picopilot i want to install ina blimp (www.minizepp.com)
so doest it work?

i'm in Franch part of switzerland near geneva (60km) in Lausanne

best regards

[workshop]

Technorama is a Swiss Science Museum in Winterthur. My company might be installing some high voltage special effects there this summer.

The PicoPilot works. :D

Jeff

[kd7ost]

Yay Jeff,

Way to go. :D

Dan

[workshop]

I ran a 16 WP course this morning and was able to really watch the UAV fly.

I believe that the minor wing rocking that still exists is a result of adverse yaw and not (so much) over control. I'm looking into aileron/rudder mixing options because 1. that's what the rudder is for ;) 2. decreasing gain will increase turning radius (I guess...) and 3. I have all the aileron differential I can possibly mechanically dial in (50%).

I'll ignore the minor pitching until I hammer out the turns. Pitch oscillations may disappear once the UAV can make a better, coordinated turn.

Jeff

[workshop]

UAVers...

Here is the video of the first test of the GPS-58:

www.teslacoil.com/files/gps-58/gps-58_test.mpg

The camera work is unsteady so we'll use a tripod next time (maybe I'll shave too). See if you guys guys agree with me that the wing rocking is adverse yaw and not over controlling (it's probably a mix but I'll take your votes).

Great Gadget: The VeeTail OMNI... Very useful in many ways... :D You'll see what I mean when you see this link: http://www.veetail.com/

I'm going to use it to mix aileron into rudder so I can get more coordinated turns without dialing down the PICOPILOT gain. It seems it can also be used to add expo to PICOPILOT controlled RC channels (why, I don't know... yet).

Enjoy the video!

Jeff

[kd7ost]

Are you using the Nav2 R or Nav2 A? (I'm processing the info :rolleyes: ) I'm thinking it would help us to know if there are MEMS rate sensors in the guidance package.

Dan

[kd7ost]

I just watched about half the video the first time then made my above post. I went back to watch the rest and heard you mention Bjorn and myself. :o You honor us. But, you'll be moving to the "instructor" ranks now yourself. ;)

OK, I'm curious how you have it all set up. You mention a gyro on the rudder. The plane appears to me to be making coordinated turns during flight. I don't see a co-pilot on the plane so am surmising you must be using the aileron version of the pico pilot and it is controlling the ailerons. (Some people use the A version on rudder)

But the A version uses a MEMS accelerometer. The software and axis implementation has the plane putting in roll, but leveling the plane by sensing yaw. (Calman filtering magic or something software geeks know about. :confused:) Your plane may have adverse yaw in roll. (Most planes do especially high wing trainer style planes) UNAV recommends setting up the plane in a manner to try to rid the adverse yaw which can cause the oscillation. I'm not certain thats what is going on in your plane. The way to rid the adverse yaw is by setting up the mechanical linkages to your ailerons to provide differential aileron throw. You do need to have each aileron on it's own servo. Basically what happens is your linkage is oriented on the servo wheel so that the servo rotation, causes the roll deflection by moving the aileron on one side high up, but the other side does not move down much. When you roll the other direction the same thing happens. The aileron moving up moves to full deflection. The downward moving aileron moves down very little. The less the better. This will provide a more axial roll without inducing as much yaw. This may be something that has to be done to stop the oscillations.

I'm not experienced with a rudder gyro. I don't know if that could be causing the problem to be less, or more. Can you fly the same course after bypassing the gyro once and just have the rudder locked to trimmed center position just to see if it is better or worse or if there is any change at all. It might be a piece to remove from the equation just during the preliminary set up so it's not a factor in the oscillation.

Dan

[typicalaimster]

Are you using the FMA CoPilot with the setup? I see something on top of the plane. Maybe this is just the GPS puck. I had the same sort of wing rocking when I had the gains turned up to high.

These two videos was some of the early testing..

http://video.google.com/videoplay?docid=8749145529195067157

http://video.google.com/videoplay?docid=5159910176775576899

Mind you that Google compresses the videos so it looks like craphola!

[workshop]

I'm using the NAV2A on Ailerons. No Co-Pilot; the hockey puck is the Garmin GPS18-LVC receiver. I have 50% differential (twice as much up than down) mechanically established. More aileron differential seems like a shame with that rudder looking at me with those big eyes... :rolleyes: Putting the rudder to use to coordinate the turns just seems to make sense AND if the PICOPILOT can control TWO surfaces.... well... umm... cool! :o

There IS a single-rate rudder gyro aboard GPS-58 but it has been disabled (gain=0) since returning from the desert. If the gyro is up (say 50%) it fights the yaw from roll and makes the rocking worse or prevents the plane from turning. However, if the gyro was receiving an aileron signal, it would move the rudder surface with the ailerons and not fight the turn but instead make it coordinated.

I still want/need rudder on my left thumb so an electronic mixer is what is needed. There is a company in England (http://www.mainlinksystems.co.uk/) that makes a "bloody simple" mixer that I'd prefer but it is easier to buy the Veetail unit locally. Icebear, you might check out the link if you want to check out PICOPILOT rudder mixing too.

Re: End of video... You guys REALLY helped me out and for that I thank you!

Jeff

[kd7ost]

Sounds like a plan Jeff. You're treading in new territory. Keep us posted. This is good stuff.

Dan

[workshop]

I'm laughing as I type this... :D

REI (a camping and outdoor store in the US) sells these $4 eyeglass cases that I'm sure are sold my many retailers all over the place. It's 100% plastic and fabric and has a clam shell design...

Here's my new Handheld GPS mount....

Jeff

[icebear]

Hi Jeff!

Back from Zurich now and happy to find a great video - really enjoyed it, and nice to be mentioned in it too! :)

The slight wing rocking that can be seen on the video could perhaps be tamed by adjusting the gain, but it'll be interesting to see how your mixer works out!

I'm awaiting some servo buffers before I'll install my Picopilot in my SuperMiss so I am gratfeul for the tip about Mainlinksystems!

Keep us posted!

/Bjorn

[workshop]

It was very windy today and I was unable to make the entire route. The feedback from the handheld GPS attached to the UAV is really valuable however.

I added the rudder mixer and removed the fixed gain gyro (now unneeded). I'll be adding 6v and 5.4v regulators to the batteries and rf filter/servo amps to the elevator (the rudder and ailerons already have a filter/buffer/amp by way of the VeeTail mixer) in the next day or two. I will also change out the 7CH PCM receiver for a 10CH PCM to have more camera gimbal control options for the future.

Tomorrow I'll test the rudder.

Jeff

[icebear]

Jeff,

Interesting to see how the plane gets blown off course. I have experienced the same when flying in windy conditions. I wonder if this suggests to little rudder authority?

Inspired by your earlier route, I reverted to my trusty SuperImpress UAV (why are my UAV's always named 'Super'?) with the Picopilot NAV-A/ALT-T and whent for a quick 1 mile route yesterday. It tracked beautifully and made all 12 WP's before heading home to circle. I noticed that my 'left' turns made larger circles than 'right' so this reminded me how important trimming is.

Here's a picture of my route - I had plenty of power left so I'll see if I can make a 3 mile route with 31 WP's next time. Not bad for a GP1100 mAh pack in that case...

/Icebear

[workshop]

Not bad for a GP1100?... That's amazing!... I use those for radio batteries! :eek:

I can't believe the difference the rudder makes to smooth coordinated tight turns (sure I know that from flying with my left thumb for seven years, but MAN puttin' two thumbs on one channel really made the UAV fly nicely). As a side benefit, it seems that the wing leveling is much more effective.

The flight was a beauty and only a nit-picker would tweek it any more. :rolleyes:
Well... :rolleyes: :rolleyes: hmmm... OK... so I'm a nit picker! :mad:

The flight path speaks for itself as you compare it to the last one I posted. Today was just as windy but from the opposite direction. Altitude data from the xTrex Vista showed I maintained 500'+-15' good thing as I was blown DIRECTLY over the smokestack (I was WELL above it... 250'+).

Since the PICOPILOT uses a yaw sensor to sense and correct roll as well as yaw (Kalman filtering as Dan opined?) I feared that the addition of more yaw response would foul what the software expects. Not the case. Improving turn coordination made for a easier airframe for the PICOPILOT to control.

Update Stats:

Planned Route: 1.6 miles
Recorded Route: 4.86 miles
Flight Time: 7:24 minutes
Max Speed: 69.8 miles/hr
Avg Speed: 39.4 miles/hr
Ahr Used: 2.33
Mileage: 2.09 miles per Ah

I need to slow down and get better mileage.... :(

Jeff

[icebear]

That's really neat Jeff! I guess you used the Veetail mixer to mix rudder/ailerons. Any settings recommended in the mix? I'll definitely look into the UK mixer you suggested!

GP1100 as RX packs! I managed to test a full 31 WP's yesterday for the first time and it was a success!
It was windy so the downwind legs were ballon shaped to say the least. Flew the course twice on two separate packs (2.3 miles each but longer in reality) and the GP1100 packs were almost empty at the last WP. Had to glide my way back as I was fearing range issues..

Interesting to see that our milage/Ah is about the same...

/Bjorn

[workshop]

The nit-picking paid off! The GPS-58 flies on autopilot as well as if I were at the controls! Bjorn’s comments about trim made me think about my servo setups. The elevator and rudder were set to maximum mechanical advantage (pushrod in servo arm hole farthest away from the servo pivot point). This resulted in 70% of servo travel producing 100% of control surface deflection and a low pot setting on the PICOPILOT. I changed the mechanical gain to make 100% of servo travel produce 100% of intended control surface deflection. This step alone removed all pitch oscillations without changing the electronic gain of the PICOPILOT.

I’m almost done with flight-testing and am getting ready to start looking into a video transmitter for spotting. Here’s a summary of my biggest lessons so far:

Computer Radio? What Computer Radio?
The autopilot doesn’t have the features one’s computer radio does. Set everything up mechanically. Then, one will understand why computer radios were invented in the first place. :D

Buy a Handheld GPS Unit:
Walk off the boundaries of the intended flight zone as well as studying map and satellite photographs before testing GPS navigation. The “real world” is a lot bigger than the map. :rolleyes:

One Channel Coordinated Turns:
Know your airframe and set it up to be able to fly perfect turns with one channel. In my case, adding 35% rudder mix to full deflection ailerons (which are set at 50% differential) via an electronic mixer (VeeTail Omni) made a HUGE difference in smooth turning and wing leveling on the flat bottom airfoil of the Senior Telemaster.

Chain of Gain:
Setting mechanical servo gain to “100% servo travel = full surface deflection” allows the in-line electronic gain of the PICOPILOT to be set at higher setting allowing for more control surface resolution.

Record Each Flight:
One must record the flight and compare it to the programmed route after the flight to make intelligent decisions on aircraft trim and autopilot settings.

Senior Telemaster Control Throws:
Elevator: Up .5”, Down .5”
Ailerons: Up .5”, Down .25”
Rudder: Left 1”, Right 1”
Mixed Rudder: Left .375”, Right .375”
Servo End Points, Mid-Points and Differential set mechanically
Servo Travel (mechanical gain) set as close to 100% as possible
Rudder Mixing via Vee-Tail Omni Electronic Mixer


Next Up: Video Transmitter

Jeff

[kd7ost]

Very nice investigative work Jeff. That's very cool you worked that out and so quickly.

Dan

[icebear]

I agree - and I liked the summary - this thread has helped me too even if my setup worked before! Nice work, Jeff!

And the new Picopilot WP editor is out on the U-NAV webpage!!! Supposed to work with the newer Mapsource.

Bjorn

PS: Did another 32 WP (incl. return to base) trial yesterday - 4 km's in 6 mins using 800 mAh = more milage :) 3 miles per Ah!!!

[workshop]

Leave it to the Swedish to get better mileage...! ;)

Way to go Bjorn... I need a bigger park to program that many WPs...

Well guys, I'm done... I flew the last route two more times this morning, in wind, and got 100% both times. I've got a nice combination of tight turns, wind handeling and level stable flight.

The next phase of the GPS-58 project is to install a 1W 2.4GHz video system for spotting and GPS data overlay. I'm going to continue here rather than move to the AP forum because I want more of a "situational awarness" system (eyes for the UAV) rather than a photography system (that'll be last, under the "payload" heading).

Work is on the horizon... My UAV R&D may slow down for a while but at least I have a platform and that was my goal. Thanks again for everybody's help.

Jeff

[d_wheel]

What radio control system are you folks using? A friend of mine tried PicoPilot and couldn't get it to work correctly with Futaba PCM. He says it worked OK with a PPM receiver, but not at all with PCM. He shelved it because he wants to be able to use failsafe.

Later;

D.W.

[kd7ost]

The Futaba PCM receivers put out pulses at 3.3 vdc. That's because of the processor they use. The PIC chips used by the UNAV units need 5 volt TTL levels to operate. 3.3 vdc pulses are ambiguous to the PIC used. There are fixes to get it to work. I use a Futaba PCM. Here's a thread describing the issues and how to interface them.

Dan

http://www.rcapa.net/forums/viewtopic.php?t=734

[kd7ost]

Sorry, looks like a load of crap. RCAPA is making you become a member and sign on in order to read all our old stuff we put there for free. Maybe I should sent them a bill for all the information I've posted. :D I'll cut and paste it here for you.

Dan

There are two qualities in some Futaba PCM receivers that can cause interfacing problems with certain electronic devices. Most notably interfacing with 5 volt TTL circuits including PIC chips or interfacing with the Co-pilot CPD4 roll and pitch stabilizing unit. The two qualities are described as follows.

Both these issues are caused by the same thing. The way Futaba processes their servo signals. The processor used is a 3.3 volt unit. This means the pulses being generated are only 3.3 volts as a logic high. TTL circuitry needs to have 5 volts +/- a small percentage. 3.3 volts is too low to be considered a logic high and can cause ambiguous operations.

The other thing Futaba does when sending the servo pulses is they send them all in parallel. In other words, all the pulses going to all the channels are being clocked out at the same time. This doesn't matter in normal operations because they're all going to different places.

This can be a problem when sending those pulses to a device where a processor reads them. Like the co-pilot. The co-pilot needs to read those pulses coming in individually. It takes in first one, (either pitch or roll it doesn't matter) then the other in order to make sense of them. Other receivers send pulse out one after another and in sequence. First to channel 1, then 2, then 3 and so fourth until it starts over again. This is what the co-pilot is looking for. First one pulse then the other.

So how do we work with these? There are a couple of ways. First, changing the voltage level of the pulse from 3.3 volts to full battery level. Typically 4.8 to 6 volts. All you need to do is install a servo buffer in line between the receiver and the TTL device or PIC chip. This device takes the incoming pulse and re-creates it to help the pulse stay intact on long runs or RF noisy environments. As a side effect, it will re-create the pulse at the same level as the battery pack it's plugged into.

Coincidentally, this is also the recommended way to resolve the issue to the co-pilot. All you need to do is to add one, perhaps two, servo drivers on one of the two signals coming in. Only one though. (It doesn't matter which one) The servo buffer causes a slight delay as the pulse gets shifted though. That means on the output, that pulse will no longer be lined up with the pulse that isn't being sent through a servo buffer.

You can also shift the levels out of a 3.3 volt receiver by installing a device like a Jomar optically isolated Glitch buster. The pulses coming into the glitch buster will be 3.3 volts but they will be re-created on the output at the full battery voltage level.

Please add any other unique situations and work around solutions you may be aware of.

[workshop]

Try not to laugh as you look at my mock-up for my tilt and pan mechanism. I’ll mount the Pan servo upside down in the nose and have the Tilt servo and camera outside. ServoCity sells some nice robotics attachments and I’ll post my progress as parts arrive.

The addition of Tilt and Pan servos has upped my servo count to six. I began to look into my power supply and decided to redo it for the fourth time.

Evolution:

Power Supply v1.0
6.0v Switching PS
5.0v Switching PS
ON when connected to Motor Battery
Problem: Possible R.F.I. from switching PS

Power Supply v2.0
5cell 1650mAh NiMH
4cell 1450mAh NiMH
DPDT Switch (ON – packs run individually, Charge – packs charge individually)
Problem: Full charge on 5cell NiMH exceeded 7.2v

Power Supply v2.1
5cell 1650mAh NiMH w/ 6.0v Linear Regulator
4cell 1450mAh NiMH w/ 5.4v Linear Regulator
DPDT Switch (ON – packs run individually, Charge – packs charge individually)
Problem: no fail-safe redundancy on batteries or switch

Power Supply v3.0
2x 5cell 1650mAh NiMH parallel into 6.0v Linear Regulator and 5.4v Linear Regulator
DPDT Switch (ON – packs run in parallel, Charge – packs charge individually)
Solution: If either pack fails, the other will carry both regulated loads. If either side of the DPDT switch fails (highly unlikely in a sealed RF box in an electric plane) the other side will carry both regulated loads. Individual charging allows for pack diagnostics. The total capacity is 3300mAh.

Jeff

[d_wheel]

Workshop, Is that a PCM receiver? If so, how does it work with the PicoPilot? Does the auotpilot activate automatically if the receiver goes into failsafe? How about issues with the mixer? What brand mixer is pictured?

Later;

D.W.

[workshop]

The receiver is PCM... works great. The mixer is a Vee-Tail OMNI. The web address can be found a few post up. Also works great.

The PCM reciever fail-safe is set to turn the PICOPILOT to ON, Throttle to HALF, Rudder to CENTER, VIDTX to OFF, Ailerons and Elevator to HOLD (i.e. N/A). I have not tested it yet.

Jeff

[icebear]

Great progress Jeff! I need to look into my power supply as well since I am relying on a regular BEC - works but on the limit I think...

And hey - I used to work for a pharma company which made those asthma inhalers! Glad to see that they come in handy in many ways :)

/Bjorn

[d_wheel]

The receiver is PCM... works great. The mixer is a Vee-Tail OMNI. The web address can be found a few post up. Also works great.

The PCM reciever fail-safe is set to turn the PICOPILOT to ON, Throttle to HALF, Rudder to CENTER, VIDTX to OFF, Ailerons and Elevator to HOLD (i.e. N/A). I have not tested it yet.

Jeff

Thanks! I don't see any line buffers so assume that JR PCM receivers don't need them to work with the picopilot or mixer. I am attempting to help a friend install a picopilot. We both use Futaba equipment, and are having trouble getting things to work correctly. He had some line buffers over-nighted in and they helped with the picopilot, but we still can't get his mixer to work. It works fine with PPM, but not with a PCM receiver even with buffers installed...

Could you create a block diagram of how you have your system wired? I assume you are going from the receiver; to the picopilot; to the mixer. Into the mixer you have the aileron/rudder output from picopilot and also an input from the rudder channel.

Later;

D.W.

[workshop]

Bjorn,

Yeah, I had to use it yesterday still hooked up to the servos... I musta looked like a real dork... :o

I've been meaning to do a block diagram so if you don't mind a hand drawn one... :rolleyes: I'll u/l today after work...

I have a couple of buffer/amps but they are buried under the wires. They are for RF noise filtering for long tail leads and the VIDTX on/off channel because of its proximity to the transmitter. The JR gear uses a "% of line" for signal output so my signal is close to 5v. I understand that the 8 Channel Glitch Buster from EMS/Jomar is a plug and play solution for servo power and signal isolation.

Jeff

[workshop]

UAVers,

Here is the block diagram for my PICOPILOT system...

Jeff

[d_wheel]

Thanks for the diagram! Ours is set up basically the same, with the exception we have to use buffers between the receiver and picopilot. Everything on ours is working except for the mixer. It simply does nothing when used with a (Futaba) PCM receiver, even with buffers installed. With a PPM receiver and no buffers anywhere, it works fine... but no failsafe...

Was on the phone with my friend this morning and he was on line and in the process of ordering a JR system.

Later;

D.W.

[lvspark]

for failsafe on that ppm system try http://h1072112.hobbyshopnow.com/products/description.asp?prod=HAN6015
I use one and it is great.

[d_wheel]

for failsafe on that ppm system try http://h1072112.hobbyshopnow.com/products/description.asp?prod=HAN6015
I use one and it is great.

There are several fail safe add-ons available, but it just means adding more "stuff" to the system. The system already has buffers in line with all of the servo leads, so adding fail safe units to each one seems to be going too far. We believe that it is best to keep things as simple as possible. Using a JR system will eliminate both of these and help keep the wiring jumble to a minimum.

Later;

D.W.

[kd7ost]

Some mixers can handle getting two pulses at the same time but some cannot. The Futaba 8 channel PCM unit not only puts out 3.3 volt pulses, but it puts out 1 and 2 together, then 3 and 4, then 5 and 6 and then 7 and 8. Depending on what channels you're feeding into the mixer, it might be getting both at once. The code used with some pic's allows for first one pulse, then the other. The Co-pilot is like the previous described. You can't give it both pulses at the same time. You have to delay one. Futaba is a little more intensive to work with. The JR systems put out 5 volt pulses and sequence them 1 through 8 before starting over. It's easier and in the long run, cheaper and lighter, less parts to fail etc, to just go that route for your UAV needing failsafe.

I need a new location to post some tutorials I had written up and posted on the RCAPA site that covers some of this.

Thanks

Dan

[workshop]

Dan,

I've got a huge commercial website that can store UAV related files. I can setup a public folder called www.teslacoil.com/uav (or something similar) and you, me and everybody else can store there. Let me know if this sounds like an option for you?...

Camera Mount
This is gonna work out great! The gyros really help the stabilize the image at least on the bench. I lashed up the system under the plane with a servo tester and the camera plugged into a camcorder. When I rocked the fuse and watched the image on the camcorder, I could see only the prop move; the scene stayed still.

I was too excited and plugged everything into the plane forgetting that the gyros only work on 4.8v. I fried one. :o So, I moved onto the physical aspects of the mounting and proceeded to cut the plane up.

The photos pretty much tell all. The first is a wiring harness that taps the 5v buss for the Tilt and Pan servos (rather than the flight control system's 6v buss). On the other photos, one can see the aluminum "L" camera bracket and how it fits into the Servo City 1/4" shaft adapter. The "G" Foam and metal spring seen above the Tilt servo were used to dampen the servo's lateral movement and to fight the gravitational pull from the weight of the camera, respectively. The complete unit with servos added 10.4oz to the nose.

Tilt ranges from straight down to slightly pointed up past horizontal. Pan is about 120 degrees. The quality of the KPC650 image is excellent; it is almost as good as my camcorder except with a wide lens. In-Flight video will have to wait until I can afford a TX/RX. :(

Balancing with a bigger flight battery (I want to fly for an hour) and the VidTX in mind will be my next chore. The under carriage hard points for the VidTX are right under the CG, so I can just add that when the time comes.

Video Power: I found a nice 5A, 12v fixed linear regulator in a T03 case that I can add up front (in the cooling airflow) that will power the camera and VidTX. I'm getting sick of the concept of separate batteries for everything but that alone is not a good enough reason to stop. Does anybody have experience with VidTX power supplies?

Jeff

[kd7ost]

Dan,

I've got a huge commercial website that can store UAV related files. I can setup a public folder called www.teslacoil.com/uav (or something similar) and you, me and everybody else can store there. Let me know if this sounds like an option for you?...Jeff

That sounds great Jeff. I'll collect my material and get you a PM or direct e-mail to start working it out. It isn't a lot of stuff. Just common interface issues that keep coming up as questions. There are pictures and text.

Dan

[Keith R.]

Looking good Jeff :)

Keith,
(that guy who works at that hobby store ;) )

[LukeZ]

I need a new location to post some tutorials I had written up and posted on the RCAPA site that covers some of this. We need to get the tutorials back into the public domain where people can have unimpeded access to it.Dan, I suppose there are some pros and cons to it, but you might also consider posting your tutorials here on RCGroups. One doesn't have to be a member of RCGroups to read the posts. And although the threads will soon become buried in the past, I for one would be sure to bookmark them, and when people asked we could provide them with the link. Not to mention they should come up in site searches.

There's nothing wrong with posting them on Jeff's site, and I say go for it. Only they might be kind of handy here as well.

Just a thought, but I'm glad you're thinking ahead about these things and want to keep them accesible, as I believe they're quite useful.


Luke

[workshop]

Hi Keith, Thanks for stopping by... I hope we get the chance to fly together soon; I'd love for you to see the GPS-58 in action. And thanks for the HeliMax single rate gyro too; it works better (smoother action at all gain settings - seems dampened a little) and is easier to set-up than the GWS PG-03 that I had been using.

Guys, Keith is a local celebrity. The DARPA sponsored auto-navigation team, of which he is a member, made mention in our local papers several times.

FileSpace: www.teslacoil.com/uav will be setup by the end of the day. I am thinking of the following file organization: Projects, Tutorials, and Resources. Files can be uploaded to uav@teslacoil.com for virus scan and subsequent u/l to the ISP. Total read access, 24/7/365 till at least 2014 (I'm paid up till then and will most likely renew). Wait till tomorrow, 5/29/2006, to u/l so I can setup the necessary accounts.

IMO… These chat/info boards are almost universally run as benevolent dictatorships. That’s OK; it’s the same way I run my company. However, policies change, governments intervene (e.g. asking phone companies to hand over user records without warrants) and info that was available sometimes gets locked up. RC Groups is probably the best place to find this stuff NOW, but my offer is a hedge against censorship of this technology or profiteering from works intended to be public domain. :censored:

GPS-58 - Headache time
I'm in the process of installing the video system power supply (I answered my own question: 4cell LiPoly on a NTE933 5A, 12v regulator) and the placement of objects (some I haven't purchased yet) is a real pain. Balance issues yes, but also antennae proximity, lead length to batteries, etc. Wow... :o

"We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard." - J.F. Kennedy

;)

Jeff W. Parisse

[Keith R.]

Thanks for the offer Jeff. Hopefully we can meet @ feild of deams (or wherever is convienient) and fly your plane. I should be able to do it mid june when school is out for the summer :D

Anyway, in reguards to that battery you bought for the camera, what you should do is bench test it and add see how long it takes to completely drain it. Once you figure that out, depending on how long it takes to drain the battey, add a buffer of time as to how long you can keep the camera on without over discharging your battery. I was thinking about a way to make a LVC for it also to make sure that you do not ruin the battery. What i was thinking about was making a LVC using a LVC. What i was thining up of was taking a LVC for a 4 cell lipoly battery and installing it on the battery lead before the regulator. Then attach the servo lead that usually hooks up with the esc and attach a micro servo (like the hs-55). Then attach a switch to the arm of the servo and install the switch BEFORE the regulator. That way, in theory, when the lipo gets to the low voltage, the LVC will send a signal to the servo to "turn off" or rotate to one of its limits. In the process of doing that, it would flip a switch that would turn off the power to the regulator, which would shut off the power to the camera and tx, and would save your lipo from over discharging. I am not too sure if that will work without any bugs, but doing something like that would prevent you from over discharging your lipo.

I hope I helped,

Keith Robertson

[workshop]

Keith,

That's a great idea but adding a electronic switch instead of a servo makes it perfect. The video transmitter will be on an e-switch and perhaps a LVC can be integrated into that. Today’s' tests suggest that I won't have to worry about LVC with the amp draw I have.

I going to rededicate the front hatch area of the plane to video equipment. The camera and gimbal hangs there as well as the pan gyro making the wires handy. Once I add the PS, battery, OSD (on screen display) and altimeter (for the OSD) the area will be heavy enough to balance the plane with the motor battery in the under-wing compartment above the shielded RF enclosure. The TBA video TX will install under the fuse at the CG. I have much more balancing range and room for a second motor battery (1hr run time) when the time comes.

Jeff

[Keith R.]

I am curious as to what the actual amp draw is to the predicted amp draw. If it is simmilar to what the predicted amp draw was, you should have about a 3 hour run time. If that is the case, i would set a timer of some sort to go off at 2 1/2 hours to let you know it is time to re-charge the battery. I cant believe i didnt think of using the electronic switch. :o

K

[workshop]

Keith,

The battery lasted almost two hours at 1.25A. So, as you calculated, the battery will last twice as long as I need it to (1hr.). That's perfect.

On-Screen Display
The OSD and video lines are all in. I am waiting on the VidTX and e-switch as they are the LAST parts to go into the never-ending money hole! :rolleyes:

The OSD is the Vizion from DPCAV (www.dpcav.com). Even though it is their low end option, it is really well made and thought out! The mini-joystick was a mini-joy to use and made set-up really fast. I positioned the white text at the top of the screen so I can pan up to the black fuselage underside to see the text under any conditions. I can also toggle the OSD off and on at the transmitter. The Vizion is perfect for electrics because it has voltage and current sensors for in-flight feedback of these two very important parameters.

I ran a separate power line to the Z-Log to completely isolate the video system power from the radio system power. The OSD on/off (channel 9) does NOT connect the radio and power buss but the Z-Log's radio lead DOES. Luckily, the Z-Log can accept 12v so I ran separate power to it's pass through connector and left the radio lead (read: radio/power) unconnected. This setup is different from what is outlined from the manual but works and provides superior sub-system isolation.


Jeff

[workshop]

While double-checking the electrical system after I installed the OSD, I noticed a 1.3 ohm ground connection between the radio/autopilot system ground (RF box) and the video system ground. I checked the motor battery lead and it was there too!

The OSD’s radio lead (signal and ground, no positive) that is meant to connect the OSD to the radio so the display can be toggled on/off was one of the culprits! The other culprit was the “unintended” ground connection between the ESC’s battery negative lead (luckily NOT the ESC’s opto-isolated radio lead) and the OSD’s voltage sensor (duh!).

The voltage sensor is super critical and I can’t use an isolation transformer because it’s DC not AC. So, I’ll forget about that potential problem until later. I HAVE to isolate the radio/autopilot from the video system however.

I designed, tested and PCB etched a custom 6v to 12v R/C opto-isolator for the task and it works great so now both systems are totally isolated. We’ll see if the common ground of the OSD voltage sensor injects interference into the video system. I doubt it, as the OSD was purpose built for electrical motor feedback via video link.

I added two side scoops to cool the motor battery compartment to a greater degree. Also I added a “Video Standby” / “Transmit Ready” switch with day bright LEDs so I can switch off the video main power between flights and still have an indicator light remind me that there is a LiPoly battery still on board.

Transmitter gets installed tomorrow after OSD test flight.

Jeff

[workshop]

UAVer's,

The attention to R.F. shielding detail paid off as the 1W video transmitter passed all of it’s tests in a VERY urban test location. Bench and airborne tests have been 100% radio/autopilot glitch free so far and even though the video receiver is a low-end model (waiting for BW Diversity), the transmitted image quality is extremely good.

In more than a month of everyday airborne testing, GPS-58 has logged more than 20hrs. of successful autonomous flight with only one unexplained glitch resulting in a flyaway. In that case, we were able to return the plane with the “manual override/autopilot on” turning method to set the vector back to home. Now that we have on-board video, we have a better R.P.V. emergency return feature.

Thanks for everybody’s help and interest; the prototyping is over. Now we are on to actually using the platform for videography as intended.

Jeff W. Parisse
www.teslacoil.com

[workshop]

more photos...

[freepride]

hy ther e,


i realy like to know more about it ,
but the link of the site is not working ? :o


what is the total cost's to asemble a plane with these gps and stuf please ?

[workshop]

The link is down because there wasn't enough (any) interest.

GPS-58 is working on agriculture in Souther California. Last week we surveyed corn fields that will soon be growing pumpkins!

The plane works great and the video is outstanding. I'm switching out components on the camera gymbal (stronger servos and better gyros). The cost? Thousands... probably between three and four $3,000 - $4,000 US).

Jeff

[lvspark]

Nice rx antenna set-up!

[winterhank]

Workshop: anything you put up under a link - I'm dying to read/view.

[workshop]

Guys,

My camera mount is starting to fail as the heat wave killed one of my gyros. The vertical camera shake is caused by the gyro. The blooming is because I don't have an auto-iris lens yet and I don't know what caused the proposing.

The landing was the worst on record for this plane. I misjudged the crosswind but the plane came out undamaged.

So enough for the disclaimer! The video is of the California coast and yes, I'm flying over the ocean under 400'. :D The location is the White Point Nature Preserve which used to be the White Point Nike Missile Site. The launch elevators, blast exhaust hoods, various hard points and buildings still exist. If JettPilot was posting this video he'd title it "UAV Targets US Missile Base" but sorry, it's just me flying with the seagulls over dry grass and water. :rolleyes:

www.teslacoil.com/gps-58/gps-58_white_point_1_mpeg1.mpg

Enjoy!

Jeff

[Mr.RC-CAM]

Nice video - that is definitely a beautiful place to fly. Much better than the dry grass and roof tops that I get to see where I fly. :)

BTW, yours is the first posted video I have seen that shows the Vizion OSD in action. Thanks for sharing!

[workshop]

Thomas (Mr. RC-CAM),

I manufacturer engineered products too. Your stuff is really well designed and made. I'd buy anything you build. Thanks for your dedication to our hobby/sport.

Jeff

[icebear]

Jeff -that was great to see a video from your project which was so much fun to follow!

Thanks!

/Bjorn

[JettPilot]

Guys,

If JettPilot was posting this video he'd title it "UAV Targets US Missile Base" but sorry, it's just me flying with the seagulls over dry grass and water. :rolleyes:

www.teslacoil.com/gps-58/gps-58_white_point_1_mpeg1.mpg

Enjoy!

Jeff

You are right about that ! The way you promote your video will get you more attention than what is in it ;)

I think you should go over to the AP forum, post it and go with the above title for the thread, you will not be dissapointed :D

JettPilot

[jparisse]

Jett,

Thanks you for the complement on the video but it’s my worst camera work so far. :( I u/l'd that video because of the beauty of the coastline. I have MUCH better video of the sanitation facility on Gaffee Street. :rolleyes: I hope to return to White Point in the next few weeks and really hug the coast for a mile or two at about 250-350' AGL. We scoped out pilot vantage points that will permit more linear flights (rather than going round and around to catch the same piece of coast each time).

In so far as the AP forum. I'm not fond of the tone that people use to talk to each other there (hence your very funny joke). The people that freak out about your videos (you don't help with your titles :rolleyes: ) and who argue endlessly about being watched by the FAA, the RCAPA bashing and the RCAPA bashing bashing is keeping me away from the fray.

I just want to fly my little robot plane with the least amount of friction as possible. I do special f/x for a living and AP is a service we do for fun, "pumpkins" and "t-shirts". I am not into this for money (yet, while I’m still using HAM links) or to trade flames with the AP Gods.

I admire your achievements and think your wife/girlfriend is hot! :D

Jeff (not in the Workshop - on the road with Laptop)
www.teslacoil.com

[JettPilot]

I have been following this thread for a while. Some of the stuff you have done with the electronics is awesome. You have chosen a great plane with the telemaster. I almost went that route myself, but I do enough high risk, high stress flying that I had to go with an EPP wing and other materials that are very crash resistant. One day I will post those videos when people get bored with and stop flaming the very tame videos I have been posting. I have to break those guys in slowly... I dont mind stirring them up, but I dont want to give any of them heart atttacks ;)

You do have some guts though flying over saltwater like that :eek: I would love to do some beach videos, but I just cant bring myself to risk it, to much electronics on the plane. I would love to fly in the desert where you did your testing, we dont have anything that cool around here. Thats a lot of hours you have put on that plane, thats what this is all about, flying a lot and having fun with it :D

JettPilot

[jparisse]

Thanks Jett, coming from you that "guts" complement really means something. I design and coordinate extremely high risk high voltage electrical stunts for a living so flying a few grand over the ocean was actually relaxing and fun like a hobby should be. :D

After talking to some professional photographers and a doing few gigs that presented less than perfect landing areas (hey, Dan, I never knew farms were so dirty :rolleyes: ), I've decided to make some airframe changes someday.

1. Counter rotating twin motors on the wing
My best flying plane is a Hobbico Twinstar with counter rotating twins. Flys and lands like a dream with zero P and T effects. I'll get a new Telemaster and retrofit the wings.

2. Move camera gimbal to nose
A no-brainer. The prop kills the commercialism of the video that I hope to make commercial someday (or not).

Jeff

[drone]

Jeff

I am ready to drill the wing hold downs using your bolt modification. I am wondering about the "struts" however. Do you always use them? I have seen comments on this and other forums about both opinions. I don't plan on acro but will be hauling both video and still cameras. Curious about your comments...

Second question is whether or not you are using any RF Chokes on the leads from either the aileron servos or the rear mounted servos for the rudder and elevator?

Thanks again for your efforts in this project...

Leon

[sodman12]

did i hear it right that you were going to remove the motor from the front and put one on each wing?


Jettpilot,

I think you should post a few more videos maby on The uav forum. i for one would enjoy seeing them!

[jparisse]

I don't have any chokes on any leads. I removed the external buffers (shown in a pervious schematic) after realizing that they wouldn't help a swamped RF environment. JR does not recommend any RF chokes as JR has much faith in their low-pass first-stage filtering. All R/C and Autopilot gear is mounted inside a RF shielded box. I used heavy duty TWISTED servo leads for all runs. I have positioned the VidTX under the shielded box and have positioned its antenna (RF energy pattern) and the R/C receiver antennae for minimum physical bleed-over.

I believe the struts are more than a good idea. Mine take just a few seconds to attach and increase the load bearing capability tremendously. My plane weighs 15 pounds.

More video is on the way. I'm out of town now (Birmingham, AL - that's why I'm no longer "Workshop" till I get back to the workshop). I have another AP gig on Friday and Nick and I want to get back to White Point as soon as we can to fly farther up the coast. I have a couple friends with boats docked at San Pedro or Long Beach. I intend to coordinate a route farther out to sea with a boat (i.e. spotter) or two waiting at a GPS waypoint.

Yes, you heard right. I am planning to create a twin motor (counter rotating) wing and place the cameral gimbal in the nose. I want to talk to some engineers about thrust lines, flat bottom wings, etc. before I jump ahead.

Jeff

[kd7ost]

After talking to some professional photographers and a doing few gigs that presented less than perfect landing areas (hey, Dan, I never knew farms were so dirty :rolleyes: ), I've decided to make some airframe changes someday.Jeff

Boy howdy are they ever. When I used the Rascal 110 as my prototype aircraft I knew I wanted rear engine and tricycle LG so incorporated that into my design. I get to fly off the paved rural roads. I still have some issues to work out in my next design to get back on gravel and two track. That engine of mine vacuums rocks and sucks them through the prop sometimes. I'll fix that in the Pegasus V2. It's tough to lose a 25.00 prop on takeoff. :eek:

Dan

[typicalaimster]

That engine of mine vacuums rocks and sucks them through the prop sometimes. I'll fix that in the Pegasus V2. It's tough to lose a 25.00 prop on takeoff. :eek:


Even with my design my prop has 'green tips'. No matter what you do something is eventually going to hit the prop. I have been flying with the same 9x5.5 prop for about a year now.

[sodman12]

you need an HD video camera or something like a full size video camera in the front. Not sure how doable that is.

[workshop]

Below is a quick summary of the upgrades I plan to make on the GPS-58 UAV. These changes come after fifty programmed missions and discussions with buyers of (other peoples :o ) professional aerial photography.

I’m looking at Neu Motors and a sealed planetary gearbox. I’ve avoided gearboxes like the plague but in this application and with quality equipment (unlike the hobby gearboxes that have give me so much trouble) I can’t beat the efficiency. I’m limited in prop selection and have decided to use matched 11x7” APC props (one will be a pusher) and have them counter-rotate.

I’ll rotate the camera gimbal 90 degrees before I mount it into the nose so that I can dispose if the “L” bracket and mount the camera directly to the spline of the pan servo (tilt and pan servos now “trade places”). :confused: ;)

Here’s the mod list and my thoughts as to the “why”…

Motor Mods:
Wing Mounted - Prop Clearance
Twin - Prop Clearance (smaller prop: two 11” rather than one 16”)
Counter Rotating - Superior Handling (no P or T effect)
Sealed Motor Housing - Farm Proof
Higher Eff - Longer Flight Times

Camera and Gimbal Mods:
Nose Mounting - Camera Protection, Better Forward View
JR Digital Servos - Better Response & Holding Torque
90 Degree Mounting - Less Mass
Auto Iris Lens - Eliminate "Blooming"
Manual Zoom - More Camera Options
Better Gyros or PicoTilt P&T Controller - Better Stabilization

It will probably a while before I make the moves. I need more time in the air. I HATE where I have my camera though.... :censored:

Jeff

[icebear]

Exciting project Jeff!
I'm looking forward to hearing more about it.

My Supemiss AP plane is finally finished and in service and I have just got my Picopilot back from UNAV for a firmware upgrade. I'm not sure you would need the upgrade since your setup is so well trimmed. The new firmware would allow for really short route legs and I'll report here after some testing.

Good luck!

/Bjorn