Hi, I am very new to robotics and honestly I call what I am attempting to build a "Robot" but it may be considered to be by some just a big RC toy. This is strictly an entertaining robot. Not equipped/expected to do any major task. I will tell you what I am attempting and you can decide. I am using rc transmitters and receivers to control servos attached to certain DPDT switches that are wired for forward/reverse abilities. I am using a Tactic 6 channel system and I have actually got a good part of the "robot" working. The head is on two channels of my receiver. This control is actually a 2 servo stack on a homemade gimbal to move the head in any 180 degree direction(up,down,left, right, diagonal) The base of the bot is actually the metal tubular frame of a Mongoose Dirt grinder. (Link to product at bottom for reference) Now I have had to do some adjustments to it such as remove the plastic body and I am using the speed controller that came on it with one dpdt switch inline in order to move forward and back at a certain constant speed (not to fast). This works remarkably well.
The steering is where I have run into a problem. I want to use a pwm controller attached to a 12 volt dc window actuator or windshield wiper motor in the same fashion as I am using the speed controller for the fwd/rev and honestly if I can get this to work I will replace the speed controller also with another pwm. Why am I wanting to use a PWM? Well it is quite simple. The motor I want to use for steering moves much to fast. By the time I activate and then deactivate the dpdt switch the motor has traveled the complete distance the wheels will allow. which is fine if I only wanted to travel in circles and never straight fwd. So I need the pwm to slow it way down, almost to a crawl, so that I might be able to go fwd at some point.
So now you are caught up on my project and here are my questions.
1) Where can I find a PWM that I will not burn out with 12volt battery? (I have looked but not sure about the amps they can handle or how many I am dealing with. Amps confuse the heck out of me)
2) Can/should I use a motorcycle battery, or should I just use the Sealed Lead-acid (2)Batteries (12v12ah/20hr) that came with the dirt grinder to run all the 12 volt motors?
3) Can anyone suggest a better way (inexpensive) to turn the front wheels? (And I have tried giant scale servos and they are not strong enough)
4) Is there anything I am not thinking of that might be helpful in making less mistakes on this project?
I appreciate any help on this. Thanks for taking the time in reading my post,