DX7 compatibility with UAV hardware.

[d_wheel]

I've started a systematic testing of the DX7 radio system with the other equipment I have on hand. First test was done with the FMA Copilot. As some of you probably know, there are issues when using the copilot with some brands of receivers. During my tests with the DX7, everything bench tested normally and flight testing was completed without incident. The two seem to be totally compatible.

Next will be with a Picopilot RTL system. http://www.u-nav.com/picopilot/picopilotrtl.html For those not familiar with this system, it is a Return To Launch autipilot. When triggered, it turns toward the location it was at when first turned on. It has saved my bacon on a couple of occasions, and could have on two others where it was not installed and equipment failure in one case, and my head up my a__ on the other, caused the models to fly away.

The only thing I dislike about the DX7 when used with autopilots is that it only has one channel of programmable fail safe. I would really like to be able to have the aileron and elevator channel go to neutral, and the autopilot enable channel go to the enable position on signal loss. The only way this can be done now is by using single channel fail safe devices on each of the 3 channels. The wiring of autipilot systems is a mess without having to add extra devices.... I have had a little success doing this by running a Y cable from the throttle channel, and using this to trigger the autopilot. The biggest drawbacks to this is (a) if the aileron and elevator are not near center, the wing leveler is not able to hold the aircraft in a level attitude, and (b) any time you retard the throttle it turns the autipilot on.... Anyone with ideas on how to overcome this please let me know.

On another note, during the last test of the Copilot, I was using a recording altimeter on the aircraft. The highest point recorded was a little over 1100 feet agl. At this point, I purposely pointed the transmitter in every position I could think of , including pointing it directly at the airplane, and never lost contact with the receiver.

Later;

D.W.

[Tom Harper]

Good info - thanks!

[Myron]

Hey DW,

I'm glad someone is having good luck with the FS8!.. Gene and I flew an AP gig today in a very rural town and we got a good steady bump- jitter- bump-bump- throttle blip-bump-jigedy jump. Totally crazy stuff. We have run them with mostly 9C transmitters with fixed freq modules and synth. as well. When you will talk to FMA, they will tell you how great they are and how Futaba's PCM isnt as safe.. I dunno, I have NEVER had an interference problems with any of my Futaba PCM gear. We have 7 of the FS8's and they have all been sent back at least once. I often refer to the FS8 as a "WM" receiver... Wasnt Me!... In reference to the jitters and throttle blips I get when were just sitting there...

Good Luck and keep us posted!..

Myron

[d_wheel]

Hey DW,

I'm glad someone is having good luck with the FS8!..

Myron

Mine is NOT the FS8 system. It is one of the original Copilot (http://www.fmadirect.com/detail.htm?item=1489&section=20) systems designed to be used with existing receivers. The results I referred to are with this being connected to the AR7000 Spektrum receiver. I had problems with the unit in the past when used with Futaba PCM receivers and wanted to see if the same issues were present with Spektrum. As far as I can tell, there are absolutely no problems when using this combination.

I have heard a lfew bad things about the combination receiver/copilot unit so have steered clear of it.

Later;

D.W.

[gwh]

Take a look at the BR6000 receiver. It has the same range as the AR6000 and fail safe on all six channels. http://www.horizonhobby.com/Products/Default.aspx?ProdID=SPM6000BR

[RaptorAP]

Hey DW, Im thinking of this unit:
Microfailsafe (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHLV3&P=7)
Im thinking of connecting it to the autopilot in case of loss of signal it will turn on, the GPS will have the one home waypoint already programmed in, Ill keep the Co-pilot on all the time since the majority of the flight will be in stability-augmented mode anyway.

Also, you dont want to share channels, ever, trust me.
Try landing an 80 inch wingspan UAV with an altitude hold that doesnt want to disengage, talk about a carrier landing!!:D:D

gwh: the BR6000 is a parkflyer range receiver, for UAV apps, the AR7000 is the way to go.

Mike

[RaptorAP]

Hey DW,

I'm glad someone is having good luck with the FS8!.. Gene and I flew an AP gig today in a very rural town and we got a good steady bump- jitter- bump-bump- throttle blip-bump-jigedy jump. Totally crazy stuff. We have run them with mostly 9C transmitters with fixed freq modules and synth. as well. When you will talk to FMA, they will tell you how great they are and how Futaba's PCM isnt as safe.. I dunno, I have NEVER had an interference problems with any of my Futaba PCM gear. We have 7 of the FS8's and they have all been sent back at least once. I often refer to the FS8 as a "WM" receiver... Wasnt Me!... In reference to the jitters and throttle blips I get when were just sitting there...

Good Luck and keep us posted!..

Myron

Myron you guys should go Spektrum, Im familiar with the problems you are having with the FS8, I talked to Gene, Ive switched over to Spektrum for heli-AP and fixed wing AP, I feel SOOO much better about going into unfamiliar areas to conduct ops.
Just a suggestion.
Mike

[d_wheel]

Hey DW, Im thinking of this unit:
Microfailsafe (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHLV3&P=7)
Im thinking of connecting it to the autopilot in case of loss of signal it will turn on, the GPS will have the one home waypoint already programmed in, Ill keep the Co-pilot on all the time since the majority of the flight will be in stability-augmented mode anyway.

I have used similar devices with ppm receivers, but there are at least 2 issues. First, my test bed does not have room to add more bits and pieces. Second, will the failsafe device work with the AR7000? The reason I ask is that when the AR7000 looses contact with the transmitter it does not stop sending data to the servos. Instead, it continues to pump out the last known good data. The failsafe devices I have used need a loss of input to activate. What we need is for Spektrum to add a REAL failsafe to the system.


Also, you dont want to share channels, ever, trust me.
Try landing an 80 inch wingspan UAV with an altitude hold that doesnt want to disengage, talk about a carrier landing!!:D:D

Mike

I can see where that would be a real bear to handle..

Later;

D.W.

[Myron]

Hey DW,

Thanks for clarifying that.. We have also talked to FMA about the copilot. In order for it to work with Futaba PCM, you have to be able to spread your channels out on your RX. This is because Futaba piggy-backs two channels per signal. ie: The Right stick on your remote is Elev/Ailerons and Futaba PCM uses 1 signal for both channels. The Copilot needs the seperation in order to work. We have one and we need to try it on my new 12Z becuase I can assign ANY function to ANY stick-knob-slider or switch. It should work with most computer radios that you can null and re-assign functions.
The sending of two channels on one signal is what FMA considers "not so good" or even dangerous.. For me having a system that is reliable is paramount. This is why I choose not to use the FS8 RX.

Raptor, Were looking at the xtremelink add ons for the 9C for most of our LOS/PIC stuff.. I do agree that DSS is the way to go..




Myron

[d_wheel]

Hey DW,

We have one and we need to try it on my new 12Z

Raptor, Were looking at the xtremelink add ons for the 9C for most of our LOS/PIC stuff.. I do agree that DSS is the way to go..


Myron

I can tell you for sure that the Copilot works fine with a 14mz and R5014 dps receiver. Don't know about the 12Z however.

Will be testing my equipment with Xtremelink as soon as they become available and reporting my findings here.

Later;

D.W.

[d_wheel]

Installation and ground testing of the Picopilot RTL have been completed without any problems. The AR7000 has no trouble communicating with this unit so I have high hopes for a successful flight. The weather isn't cooperating so no flight test as of yet. Maybe this weekend.

Later;

D.W.

[d_wheel]

Hey DW,

In order for it to work with Futaba PCM, you have to be able to spread your channels out on your RX. This is because Futaba piggy-backs two channels per signal.

Myron

I know that is what they claim, but if that were the case it would be even worse with the 14mz and I have used a R5014 receiver/Copilot combination without any problems at all. I am personally convinced that it is a signal level problem, not one of simultaneous pulses.

Later;

D.W.

[d_wheel]

It was WAY to cold and windy for my old bones, but I got out and tested the RTL unit anyway. After 2 short flights to make adjustments the airplane happily headed back to the launch point each time the unit was activated. Had so much fun that I ran the battery pack down and the speed control cut motor off. However it was noticed while the airplane was high enough to make a landing within 20 feet of where it took off. Looks like the Picopilot and Spektrum 7 work well together.

Next test will be with a Picopilot NAT (http://www.u-nav.com/picopilot/picopilotnat.html) (Nav/Altitude/Throttle) unit. That is if I can figure out how to stuff it all into the small test aircraft... This unit provides altitude hold, speed hold, and a 32 waypoint autopilot. I have been using it on one of my powered sailplanes with a course set up that flies over areas that are known to be good thermal producers. I set it up at about 1/4 throttle and it slowly flies the route. When a thermal is encountered, the airplane starts rising. It will then put the nose down in an attempt to hold altitude. It then picks up speed and the motor begins coming back to try to hold a constant speed. These are my clues to take over manually and circle in the thermal. I usually do this with the transmitter in my lap and relaxing in a folding chair and a cool glass of ice tea in my hand. A lazy mans way of thermaling perhaps, but very relaxing.

At any rate, I will let everyone know how this system works with the DX7.

Later;

D.W.

[d_wheel]

Was able to “shoe horn” the complete Picopilot NAT into my EasyStar For testing its compatibility with the Spektrum 7 radio. The system consists of 3 separate circuit boards that are shrink wrapped into a single unit with foam separation between each. The GPS antenna/receiver are shrink wrapped together as a separate unit. The top circuit board contains the altitude hold circuitry, the center is for speed hold, and
the bottom is the navigation/autopilot board.

One of the major problems I have encountered over my experience is that the wiring ALWAYS turns into a rats nest inside the smaller aircraft. With the picopilot, it seems like the wiring takes up more space than the actual boards. On each board, there is an input cable which plugs into the appropriate channel on the receiver (elevator, aileron, or throttle). Output cable that the appropriate servo is connected to. An enable which plugs into one of the receiver slots, and a cable with a 2 color led attached to indicate the status. On the nav board, you also have a cable for GPS input. The 3 enable cables are plugged into a 1 input/3 output cable so all can be enabled with one channel.

My first attempt was to just push it all into the fuselage, which worked, but the wiring was pressing against both receivers and intermingled with the receiver antennas. Just couldn't figure out any way to make it neat. Not good in my opinion. After looking things over, I came up with the following. By removing the outer heat shrink which holds the 3 boards together, I now have 3 separate boards that can be placed in different positions. The nav board fits nicely in the cavity on the bottom of the removable foam canopy. All of the wiring is held in place neatly by pushing tooth picks into the foam. I then hollowed out the foam on the outside of the fuselage on both sides. These cavities were made 2 times longer than the boards which gave plenty of
room to hold the wiring. 2 inch wide white plastic tape covers these up nicely.

I now have the system installed and ground tested, only waiting on a descent day for flight tests. As many of you probably know, getting a system of this type fine tuned usually takes several flights. I usually only enable one function at a time getting it working nicely, then moving to the next. However, my main goal is to see if it is all
compatible with the DX7, so won't really try to optimize everything before making my report here.

Later;

D.W.

[Dan_Jones]

Could you please take a picture? I am about to buy a E* and I am curious to know what I am getting myself into! :D Thanks!

[d_wheel]

Could you please take a picture? I am about to buy a E* and I am curious to know what I am getting myself into! :D Thanks!

Hello Dan,

If you are planning on using the Easy Star stock (not for uav purposes) then you have nothing to worry about. The fuse is plenty large enough for a battery and receiver. The servos are mounted externally, that's what gave me the idea to mount the circuit boards in this manner. If you are wanting to see how I did it, the next time I have the tape off of one side or the other for some reason, I'll take a picture and post it here. If you are just wanting to see pictures of the airplane in general, go here (http://sdwingmasters.com/easystar.htm) and you will find a wealth of pictures as well as valuable information.

Later;

D.W.

[Dan_Jones]

Thanks DW,
I was thinking of using the E* as a UAV. The hardware would need to be the size of the RCAP2 system but incorporate leveling, altitude and airspeed control in the space that the RCAP2 currently takes. One major way to do this is eliminate most of the wiring, which you said is a lot of the problem. In fact, one could use the SaprkFun UAV board in the E*. (I think...) So space management is pretty crutial but looking at the big picture, the functionality crammed in the E* could be as much as or more than the larger Telemaster planes. That is a very cool concept! I am excited to see where it goes from here.

[d_wheel]

Thanks DW,
I was thinking of using the E* as a UAV. The hardware would need to be the size of the RCAP2 system but incorporate leveling, altitude and airspeed control in the space that the RCAP2 currently takes. One major way to do this is eliminate most of the wiring, which you said is a lot of the problem. In fact, one could use the SaprkFun UAV board in the E*. (I think...) So space management is pretty crutial but looking at the big picture, the functionality crammed in the E* could be as much as or more than the larger Telemaster planes. That is a very cool concept! I am excited to see where it goes from here.

After finishing the PicoPilot testing, the next step will be to install my RCAP and see if it is compatible with the DX7. I think I will have to reverse my present installation by putting the receivers on the outside of the fuselage, in the cavities now holding the PicoPilot boards, and place the RCAP and leveler inside. I haven't measured, but it looks to large to fit into the outside cavities. At this time, no altitude or airspeed hold is planned. This could change if the altitude hold board (http://www.rcgroups.com/forums/showthread.php?t=633795) from eladiomf arrives before the testing is completed.

Keep us informed of your progress please.

Later;

D.W.

[d_wheel]

After waiting most of the day (several days actually) for the wind to die, I was finally able to test the PicoPilot. All went well. It appears to be happy working with the DX7.

UP next, the RCAP.

Later;

D.W.

[MisterCalhoun]

After waiting most of the day (several days actually) for the wind to die, I was finally able to test the PicoPilot. All went well. It appears to be happy working with the DX7.

UP next, the RCAP.

Later;

D.W.Any updates on this? I am currently flying an EZ* with the DX7/AR7000 and am interested in installing a PicoPilot. I'd love to see some pictures of your install. Thanks!

[d_wheel]

Any updates on this? I am currently flying an EZ* with the DX7/AR7000 and am interested in installing a PicoPilot. I'd love to see some pictures of your install. Thanks!

I have now ground tested it with the RCAP3. The original RCAP is just too large to fit in the fuselage. It appears that everything is working normally. Once again, we are having stormy weather here in west Texas, so it looks like monday will be the first day good enough for flight testing.

Later;

D.W.