How easy is it to to connect the controller to an R/C radio?
Very easy. The AX2550 will connect directly to two R/C radio channels for commanding each motor. One additional channel can also be connected to the controller to trigger on-off outputs for commanding accessories. How can the controller be used to remote or computer control a full size car The challenge with a large gas-powered vehicle is the force with which to activate the controls which far exceeds this of the heaviest-duty RC servos. This is particularly the case of the brake and steering activation. When operated in the position mode, the AX2550 can be used to create very high-power servos capable of such operation. See a detailed description on how to do this here. Can the controller be used in Underwater Robot applications This is a common application of the controller. One controller can be used to control two thruster. Typically, a second controller is needed for a third axis.Best performance is achieve by incorporating the batteries in the sub.