UNAV PICO TILT Controller

[air]

Unav Pico Tilt Page (http://www.u-nav.com/picotilt.htm)
Any thoughts / comments / current users?

[kd7ost]

I don't own one yet, but it's on my list of gear I gotta try out. I like the concept a lot. I had planned on using a spare co-pilot and placing it on top of a moveable camera roll and tilt stabilizer. But, I already have one of those on the plane. I'm using a barometric sensing altitude lock though and not using the pitch control from the co-pilot. During calm conditions I don't see much movement from my plane. But once the winds get 10 to 20 mph I see some pitch and roll changes as the devices work to keep up. The pitch changes are noticeable especially when heading into the wind. I get a fair amount of motion in the camera when this occurs. I like the idea of not having to use a spare co-pilot and building a mount that sticks out the top of my fuselage. This looks much cleaner. It also doesn't need the calibration process etc. I just have to figure out whether to use a pair of high speed servos or not in my plane. It also keeps the camera pointing straight down if you roll. It's a fairly new product but Dave at Unav told me he couldn't get his beta testers to give up the test models. Thats a good sign.

Good luck and I would sure like to hear your results if you try one out.

Dan

[air]

Hi Dan,
Thanks for the reply, I'm hoping to buy a picopilot & possibly this item in the next few months.
I assume one has to build their own gimballed mount for use with the controller?
It would be nice if there was a range of hardware available to go with it.
Best regards,
Fionn.

[danstrider]

Try http://www.servocity.com/html/servo_mounts.html for a quickie pan-tilt mount that you can rotate and make a tilt-tilt mount (twist your head around, it's just in how you mount the 1st servo to the plane).

I don't know if anyone will know, but does the PicoTilt drift over time? For example, say you were holding a straight-down view and flying for 60 mins. Will the gyros build up error over time?

Also, I can't quite tell from the pic & explanation, but does this stablize AND let you control the mount? It almost looks like it does for pitch, but I can't tell for roll.

Dan E.

[air]

Cheers Dan, looks good.
I was wondering about drift myself, some dynamic orientation sensors that I was looking at some time ago used arrays of orthogonal magneometers and accellerometers to reduce this problem.

I agree that it is unclear as to what its functions are exactly, i think that the unav product information in general could do with being more descriptive & possibly give some information on sample uses or whatever.

[kd7ost]

I don't know what propietary method was used, but there is no drift. There is no independant control over the unit's ability to pan, tilt, rotate or anything. It was designed to keep the camera looking right down at the ground in the midst of unwanted roll and pitch changes. The roll will stay stabilized within +/- 2 degrees even if your platform rolls up to 45 degrees. It will keep pitch stabilized too but it will read your own elevator input and not keep the pitch looking straight down if your trying to pitch up or down. If you aren't inducing pitch changes then it will correct the camera mount on pitch.

I like the sounds of this thing as a possible replacement for the co-pilot. The co-pilot is a great device but certainly has a few holes in it if your using it for a camera platform.

Dan

[air]

That does indeed sound promising and great value at the list price.
I'm not interested in the ability to move the camera manually for my application, prefering
to have it vertical at all times. Indeed I would prefer if it stayed level at all times even during a climb. I suspect that it would be easy to get the unit to do this anyway, even if one had to connect a spoof elevator input.

[kd7ost]

That does indeed sound promising and great value at the list price.
I'm not interested in the ability to move the camera manually for my application, prefering
to have it vertical at all times. Indeed I would prefer if it stayed level at all times even during a climb. I suspect that it would be easy to get the unit to do this anyway, even if one had to connect a spoof elevator input.


Agreed.

[philgib]

To have the camera always pointing down, I am personally using 2 basic servos for pan and tilt NOT electrically connected to any receiver, so without power.

Gravity and servo natural friction allow the camera to point at the ground but does not swings back and forth. If u r using a light camera, gravity won't work well, so just use a mini-servo.

Using pure friction may not be too good on a long term for the servo, but I do not really care and will replace it if it fails.

You would be surprised as this stupid solution works really well. I have adopted it on a kite which generates lots of camera swing. What I like is that friction allows for a smooth camera correction and not a speedy one as I have read for a pilot or a picotilt.

[patrickegan]

I’ve seen a mock up in action and it’s a little dandy. P

[workshop]

Guys,

Here's a quick preview of the Tilt/Pan head I'm working on for my GPS-58 UAV (Senior Telemaster + PICOPILOT Thread). The shaft adapter came from ServoCity... The Pan Tray is homemade from aircraft ply and designed to carry a single rate gyro for the Tilt Servo (that way, no matter which way the camera is pointed, tilt error is resolved - i.e. pitch correction when the camera is facing forward and roll correction when the camera is pointed sideways.

Does the PICO-TILT do anything besides 2 axis correction?

Jeff Parisse
www.teslacoil.com

[Steve McBride]

Guys,

Here's a quick preview of the Tilt/Pan head I'm working on for my GPS-58 UAV (Senior Telemaster + PICOPILOT Thread). The shaft adapter came from ServoCity... The Pan Tray is homemade from aircraft ply and designed to carry a single rate gyro for the Tilt Servo (that way, no matter which way the camera is pointed, tilt error is resolved - i.e. pitch correction when the camera is facing forward and roll correction when the camera is pointed sideways.

Does the PICO-TILT do anything besides 2 axis correction?

Jeff Parisse
www.teslacoil.com

Any ideas on how well a heading hold gyro would work on both pan and tilt?

[workshop]

Not sure... But check out the "Gimbal Video" thread... is this what you want to do?....

Jeff

[lvspark]

I saw the pico tilt and it looked like it worked very well. Only reservation I have is it looked a little "jumpy" to me..

[speckstein]

By the way: I 've heard pico pilot is completly unsuitable for less stable aircrafts
and it doesn't support any airframe/tail configuration than trainer-standard.
My team colleagues want it for test flights with our flying wing....

[air]

Its no secret that the picopilot is not suitable for flying wing configurations, this has been discussed on these forums before. The u-nav site makes it quite clear what type of airframes and air speeds etc the pico pilot is suited to.

[kd7ost]

Pico Tilt and Pico Pilot are two different animals. This thread isn't about Pico Pilot. ;) Comments are correct though. Pico Pilot guides a stable airframe without pitch sensitivity issues.

Dan

[lvspark]

Wonder how well the pico tilt would level an airframe?? No need to worry about horizon sensing.. ???

[jparisse]

I'm still not sure how the PicoTilt differs from two single rate gyros. I'm using two Futaba G190s (one for yaw one for pitch on the camera mount) and they seem to work great. Does anybody know if there is an additional benefit of the PicoTilt over two gyros?

Jeff

[longjeng]

I am new player for UAV system, we hope to build a stabilizer mount for camera. Would you kinderly tell me the model of Tilt gyro for for PICO TILT controller. Thanks

[patrickegan]

Why don’t you spend the time and money to develop your own system?

[kd7ost]

Wonder how well the pico tilt would level an airframe?? No need to worry about horizon sensing.. ???

I wondered that same thing but it won't work according to Dave at UNAV. Here's a cut and paste from his FAQ's.

"How does PICO-TILT work? PICO-TILT is designed to stabilize a camera mount in a moving vehicle . The 1"x2" circuit board outputs RC position commands to the PITCH and ROLL servos to keep the camera mount steady while the vehicle bounces around. It can be used on a three axes RC camera mount with the following mechanical configuration; The camera is mechanically mounted to the PAN servo ( controlled from the RC receiver ), which is mounted to the PITCH servo, which is mounted to the ROLL servo. PICO-TILT automatically keeps the PITCH and ROLL level (except during coordinated turns). The PITCH servo command can also be manually controlled from the RC receiver. PICO-TILT was designed for airborne mapping applications where it's important to keep the camera pointing straight down to minimize the error between the vehicle GPS co-ordinates and the ground GPS co-ordinates. PICO-TILT is not recommended for vehicle stabilization."

During a coordinated turn, the sensor would not detect Yaw, roll pitch etc. The plane has to be trying to go one way while the sensors trys to stay straight. Seems like there's got to be a way to do it though. Dave is a bit of a bear to get answers from. He can't understand why I don't understand it all. He needs a Tech support that's people oriented.

Dave is also dead set against stabilizing the aircraft with a co-pilot. That's a shame for the Aerial Photography folks because as far as I can tell, there are no products out there that do what the co-pilot does, does it as well and does it for the cost. To me, the last thing I need is a camera ship rolling all over the place while I try to get lined up for a vertical picture on a photo run on a huge field with a cross wind.

I guess that's where the pico tilt could come in but then you're dealing with additional, cost, parts count and building complexity. Making the plane fly coordinated turns, then stabilizing a Two axis camera mount inside of the fuselage is two electromechanical steps to get the camera looking straight down. On the other hand, if you just stabilize the airframe so it fly's flat, (That means aileron ships in use) Then you can mount your camera looking straight down and have a simple and effective platform.

So far, only a FMA co-pilot on the roll axis with ailerons does that job real well. It just has that IR thermal horizon issue. I still contend it works for me 95 percent of the time. When someone is paying you for pictures, you do what works.

Dan