I was wondering if I could program some kind of autonomous code to kick in if we have a radio signal dropout. Would this work?
No, because as a safety feature, the robot disables all the outputs when there isn’t a radio signal.
Why don’t r/c cars do this? I forgot to raise the antenna on my transmitter and then couldn’t figure out why I lost control when my car when it got about 200 yards from me. :ahh: It is a little disturbing when your r/c car hits a curb at 45-50 mph :eek:.
Well, thinking about it, when disabled, do servos return to their center location? If not, they could be disabled when the radio signal is lost, but there is one servo for throttle and one servo for steering, so it would keep going at it’s current speed and angle/turning degree which is what it does.
I think your RC car was operating on static. I’ve seen cheaply made rc cars jerk around when the transmitter isn’t working…
You shouldn’t have any problems with reception at competition; the signal is very strong and if it isn’t, everyone’s robots would be jerking around. That would be FIRST’s fault, not yours. What were you doing when it dropped out? I haven’t seen the radio drop out at all when we were doing anything.
I know that the signal at competition should be good, but was wondering why they don’t put a safety feature like that on some of the radios used by r/c cars. And my car was just definately out of range of the transmitter. Also…it wasn’t cheap at all.
At the risk of continuing a threadjacking, they make fail-safes for nitro-powered R/C cars. I’m not too familiar with them, but they’ll return a servo to neutral (or full brake, can’t remember) if there’s no signal.
You Can also program in a “heart beat” that shuts down the bot after radio connection is lost 
Nitro cars don’t necessarily have a brake, they just sort of slow down…slowly until they’re at a full stop, but probably the servo you had just left it at the position it was at before because I know that there is supposed to be a spring or something like that that releases the throttle and brings the servo back to neutral, so maybe the spring that was in your car had fallen out…I dunno…I may be totally wrong. But nitro cars are cool. What size is yours, 1/8, 1/10?
On their own? No. In RC cars? Dunno. On the FRC? Yes, because when there is no signal, all PWMs go to 127.