This article was originally published in RC Driver’s December 2015 issue.
At RC Driver we get to drive a lot of cool vehicles for testing, but there have been times recently where we’ve been jealous of the editors over in our sister magazine’s offices on what they are testing. Lately they’ve been raving over some FPV racing drones coming into the office. We see them testing out new goggles at their desks and flying the racing drones in our parking lot. That of course got our minds working on how we could use FPV in RC cars. Using FPV in cars is not new; there are lots of people trying it. So we wanted to take it a little further and devised a cool way to use FPV in RC. The project you are about to see may look a little crude since it’s a work in progress, but we wanted to share the fun of what we’ve been experimenting with.
Drive with head tracking FPV
After talking over what vehicle category would be suited to outfit with FPV, we decided on trail trucks. Since faster vehicles like an 1/8 buggy or monster truck are so low to the ground, we felt the fast motion of the car and the bouncy ride would be a bit too much for the senses. So mounting the system on a trail truck where you use slow moves to clear obstacles felt like the best option.
Our next thought was whether we should just slap a camera in a trail truck. As I mentioned this has been done many times. We wanted to be a bit more unique. We found an FPV camera set up on a pan and tilt gimbal available from HobbyKing that could be bolted to our vehicle. HobbyKing also offers a Quanum budget DIY goggle kit and head tracker unit that would allow the camera gimbal to move wherever we turned our head while wearing the goggles. This will allow us to look at obstacles while driving on the trail. To complete the FPV setup we needed a few more items. From HobbyKing we also grabbed the Skyzone Plug & Play FPV 500 set to transmit the video. A Turnigy 11.1V LiPo battery was selected to power the goggle setup. The signal for the head tracker mounted to the goggles needs to be sent through a trainer port on the radio in order for the gimbal to move on the truck. Since car radios do not have a trainer port, we modified a Tactic TTX850 airplane radio to use with our project. We swapped gimbals from left to right so the throttle stick had a return to neutral spring. Then we programmed the head tracker to transmit to the pan and tilt servos using channels 7 and 8 on the receiver. Now it was time to pick a machine to attach it all to.
Axial’s Jeep Rubicon SCX10 seemed like the perfect choice to set up the FPV system on. The camera gimbal bolted right to the driver’s seat with just a slight modification by cutting a portion of the seat for a better fit. The front Lexan windshield was removed for camera clearance as it moves. A power wire was run from our truck’s Tekin ESC to power the camera and transmitter harness. The truck was programmed to run with a 3S pack to properly power the FPV system and the truck at the same time. The extra power in the truck was an added fun bonus.
There is some wiring involved to get everything hooked up and if you go the gimbal route you will need to download HobbyKing’s head tracker program to set the parameters of the head tracker to where the end points need to be.
For some this would be good enough to go out and have fun. But we tend to overthink things; we wanted to have an FPV competition. We wanted to send the truck out similar to a real trail truck event where a spotter or trail buddy points out how to progress on obstacles. So the thought is, the FPV trail truck goes off on the trail with a person as a trail buddy to point things out. For better communication between the FPV driver and the Spotter, we used Midland walkie-talkie radios with an ear piece and voice activated microphone. Now our FPV setup was complete. We made a small course in the woods and I drove the rig FPV while Tony walked alongside the truck on the trail, communicating with me what I saw and how I had to approach parts of the trail.
Well I’d love to report things worked flawlessly, but this technology is still on the new side and we encountered some signal loss issues with the camera that limited us on how far we could go. Driving the Axial Jeep when we could see was a blast. You look right down over the hood of the truck to see what’s in front of you. Then if you need to see what’s on the sides, you can simply move your head and the camera gimbal will move instantly to see where your head is pointing. The ride is a bit bouncy and jittery as the gimbal is bolted to the body which is moving and jolting on the trail, but after each of the editors at the office tried it, they overcame the bouncy effect and had a great time trail driving from the seat of our SCX10 Jeep.
• Axial 1/10 SCX10 2012 Jeep Wrangler Rubicon 4WD RTR, AX90028
• Skyzone FPV 500-SET, 544000005-0
• Quanum DIY FPV Goggles V2, 9171000702-0
• Quanum 3 Axis head tracker, 9171000542-0
• Pan & Tilt Gimbal for FPV, 263000028-0
• Turnigy 2700mAh 3S 20C LiPo Pack, 9472000019-0
• Tactic TTX850 8-Channel SLT TX w 8Ch Receiver, TACJ2850
• Tekin FX-R Forward/Reverse Brushed ESC, TT1091
THE LAST WORD
We’re pretty excited about our venture into surface FPV and think we came up with a neat spin on how to hit the trails with a trail buddy. I think it would be cool to see FPV worked into the car world and the trail truck segment is certainly a great segment that is interested in trying new things and possibly getting this type of driving going as a more mainstream part of RC. If you have an FPV project you’ve been working on or have ideas about it. We want to hear from you. Send us an email or some pictures to firstname.lastname@example.org