General Category => FPV at KRCM => Topic started by: Deerslayer on November 18, 2017, 09:34:36 AM

Title: Simple Pan/Tilt System
Post by: Deerslayer on November 18, 2017, 09:34:36 AM
Wilf and I obtained Foxeer cameras from Banggood. Wilf has used his quite a bit, mine awaits its first flight. I wanted a Pan/Tilt capability to play around with, something that was simple and cheap and compact.

I came up with the system depicted here, after some mockups in foamboard and old  hotel room plastic keys. This setup is made from thin plywood, hot glue and a patch of Velcro. I had some 5 gram servos lying around, which are ideal.

My idea is that this can simply be mounted on any of my planes, connected to a  5.8 GHz transmitter and probably with an OSD in between those two items.

As for how it can be used: On a flying wing, where there is no Rudder, that channel can be connected to the Pan servo. The Tilt servo, which is less likely to be used, can be connected to a knob or slider, or even to a 3-position switch.

On a plane which has a Rudder, there are several options for the Pan function: Use a separate channel and either control it via a knob or slider, or, mix that channel to the Rudder in whatever proportion is desired and then set up a Flight Mode to enable that function, possibly even disabling the Rudder itself during this Mode.

As for the Tilt function, if you were using a sailplane, then you could have the Throttle stick available to be mixed in to become the Tilt control, with or without the Motor enabled. I would likely do this with a Flight Mode that sets the aforementioned "Rudder" stick movement to control Pan and the "Throttle" movement for Tilt. This means that your Left stick is the camera controller while the Right stick remains as the aircraft flight controller.

If you think about it, when you fly in a real aircraft, your vision will tend to slightly lead any turn you initiate. (You do more extensive movement when performing a clearing turn prior to doing any aerobatics  or during flight in busy skies, such as thermalling in a gaggle with other sailplanes). During the resultant bank, you have already tilted this field of vision, even if you did not move your head up or down at all. At least in the case of my Mobius, with its original lens, it is already wide angle, so unless I wished to look back over the tail, I probably need very little movement in either the Pan or Tilt plane. What I can envision the Tilt  for is to perhaps have a fixed, slightly downward, setting that would be useful while setting up an approach - or possibly to help figure out where I am if I am FPVing and get lost!
Title: Wilfs Simple Pan/Tilt System
Post by: Deerslayer on November 28, 2017, 07:48:05 AM
Wilf has taken a slightly different approach. Here is his very neat Pan/Tilt system, as mounted on his new Sky Mule (attached pictures).

Some of the differences between his and mine:

I use standard Turnigy 5g servos hot glued onto the camera platform. At least at this time, my system uses a base which can be Velcroed onto whatever plane I want. This is the most compact and adaptable arrangement I could come up with.

Wilf uses Turnigy 180 degree sweep servos, one being mounted into the camera platform for Pan while the other is mounted into the base, to Tilt the camera platform itself. The Pan servo may be useful for gazing around to extreme angles. Tilt would likely never require much movement but, hey, he had these servos itching to be put to use, so ...! His system is slightly less compact than mine in some ways. He solidly mounts most of the servo into a cut-out in the plane, so it is less versatile, i.e., more effort to change to a different plane. However, he gets a more solid mount and his Tilt mechanism, I think, works out to be better than mine.

The other difference is that Wilf's system has actually been flown, while mine is still "ridin' the pine" as the hockey players say.   :(

A long time ago, Flypaper gave me a couple of little solid state gyros from helicopters. I plane to set one in between the receiver and one of the two axes, probably Tilt to start with. My Fun Cub is one of my test vehicles and I will probably try my Pan/Tilt system on it first.
I already use 7 channels of the DX9, so that leaves me with 2 for this camera system. No stabilizer for the plane, so having one or both of my camera system's axes stabilized may be worthwhile.

Wilf also has a couple of these little gyros kicking around, so he will probably beat me to trying this out, too!
Title: Simple Pan/Tilt System and Fun Cub
Post by: Deerslayer on December 12, 2017, 11:16:41 AM
Well, there are few more versatile planes than the Fun Cub to do everything from learn the basics of r/c flying, aerobatics, land/snow/slush/water flying, messing around with various mixes and just having fun. I use mine as a test bed to try out various ideas, especially more complicated things like multiple Flight Modes and mixes, sometimes transplanting the results over to my sailplanes or other aircraft.

So, along comes FPV (for me. a bit late to the game!) Having tried Mobius-based video work on various platforms, including the Fun Cub, Skipper, a couple of my deltas, the Optera and the Black Widow wing, I figured FPV was overdue to try. I did so, on a couple of that above-mentioned planes but, having seen Wilf's progress, I decided to move along to a FPV-specific plane.

Meanwhile, the Fun Cub was the place to try FPV, and my Tilt/Pan setup. Great success! The Cub proved to be an ideal platform - rock solid, slow flyer, no sudden stall/spin tendencies and very flexible landing gear. I have had a number of complete flights under the hood (Headplay goggles), using the Foxeer camera on my mounting system and the 5.8GHz video transmitter. It practically takes off and lands by itself.

The physical arrangement for the FPV camera + Tx is a replacement Cub canopy I made from balsa. Having already used 7 channels in this plane, I plunked in a Lemon 10-channel DSM2 receiver, as I needed 2 more channels. In hindsight, an 8-channel would do, as I have not found the Tilt function to be of any real use; however, I haven't had much time to play with this stuff, so you never know.

In addition to other Flight Modes and mixes I already have on the Fun Cub. I set up 2 switches associated with the Pan function. I like to mimic what would take place in a real airplane, i.e., what does a pilot do during taxi, takeoff and normal flight and landings. The Pan and Tilt servos are set to a slightly slower than standard speed, to provide nice smooth movements (which also avoids the tendency to cause vertigo!)

As I am taxiing, Pan is enabled and coupled to Rudder, so that the pilot can look around for situational awareness and avoidance of obstacles. The amount of mixing is around 20%, as you just need to look around normally and the camera is quite wide angle. As well, at any time and in any Flight Mode, I can pan via the knob on the DX9. 

At any time, normally in the air, I can switch in coupling of Pan to Aileron. It is mixed perhaps 20% to Aileron. The result is similar to what a pilot in a real aircraft does, i.e., shift one's vision to the direction they are beginning to turn, returning to straight forward once the turn is established.

Note that, if one left both Rudder and Aileron coupling to Pan, a properly coordinated turn entry would result in the 2 commands to Pan being additive. That could be helpful to know, and to utilize.

I haven't done much with Tilt. It is assigned to the Right Auxiliary Trim lever. I suppose one might want to mix it into Elevator during certain aerobatic maneouvers. For instance, in a real aircraft, during a loop you may tend to raise your vision toward the inside of the loop, lower it to normal at the top as you relax the stick and then again raise your vision toward the top of the canopy as you pull through the last half of the loop. (I have done may loops in real sailplanes and it is easy to think through what you are doing in real time; things happen much quicker with models!) If you are thermalling, you do tend to look around and up/down a fair bit, especially if there are other aircraft in close proximity and/or or soaring birds available to point out good lift.

This stuff is great fun. My original plan was to try it out on the Fun Cub and then transplant the FPV gear to the newly acquired Penguin FPV plane. Now, I have had second thoughts and plan to leave the Fun Cub fully geared up and buy a second setup for the Penguin.

If I want to do video recording on the Fun Cub, the FPV setup could do it. However, there are 2 issues: the FPV camera sees the prop, which makes for messy video work; the video recording would take place via the ground station, which results in a noticeably degraded result, compared to the in-camera recording. The solution here is to once again mount the Mobius out on the Fun Cub wing, which works perfectly to solve both problems.

The ideal FPV aircraft, as I see it, is a pusher. The Bixler (Roger's machine), the FliteTest plane that Wilf built, the Sky Mule twin that Wilf now has, the Penguin, or any of several other popular designs work well. The possibilities are endless!