Before I continue, this is the remote control I decided to use. It's a Futaba 2DR AM R162JE R/C with 2 S3003 servos running at 27 Mhz. I simply wired the two channel outputs from the receiver to the SaberTooth 2X12 motor drive control. The SaberTooth has a setting to accept R/C signals and that's all there is to it. SaberTooth will also power up the R/C receiver so you don't have to use a power pack.
This is an easy R/C control to get into. First the price; I picked it up at Amazon for $50 including shipping. There are two channels.... throttle and steering and that's all you need. If the transmitter stops transmitting, SaberTooth has a dip option that will stop the drive dead in its tracks, which, is a great feature. The last thing you need is the robot to run wild if you lose the wireless connection.
It took some time to get to this R/C. My first choice was two SPLat controllers with radio options along with a modified game joy stick. I actually did get a proto-type working with a game joy stick but it was proving to take a great deal of time and money.
Next I bought an old R/C along with a load of receivers and servos off eBay without doing the necessary research on R/C controls. As a result, I discovered that the batteries to run these things cost an arm and leg and there wasn't one receiver whose crystal matched the transmitter's frequency. Crystals cost the other arm and leg. On top of all that, I had 7 channels along with trims and options that would easily befuddle a 747 commercial pilot. With the new found knowledge gained from this adventure, I settled on the Futaba 2DR.
The whole idea of hacking is not to invent but to "steal" technology that was intended for something else. Building a wireless system from industrial embedded controllers was inventing. On the other hand, the R/C was intended to control a toy car or boat along with two servos; I hacked the servos for their connection wiring harness and wired the receiver into the SaberTooth. A slight "steal".
The video you're about to see is the field test of the robot thus far with the wireless system installed. One word of caution. When I was demonstrating the robot with the original wired controls to my brother-in-law, I accidentally ran over his foot. I expected him to jump back when I came close but he didn't. He was playing chicken and expected me to veer off at the last moment. I didn't. I seriously considered taking him to the hospital as he desperately tried to conceal the pain shooting up his leg from the crushed foot. Well, his foot wasn't crushed and the pain did subside but a lesson learned. As tempted as you may be, don't play chicken with this baby.
Wireless Control Drive System Field Test
One of the characteristics of the robot you may have noticed in the video was the tight turns it could perform and its ability to stop on a dime. Good characteristics if you plan to deploy robot in a area populated by people.
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| View of Transmitter Wired to the SaberTooth |
Next: Modification to add a couple of shelves above the control box for a laptop and a missile launcher (He he he he).
