Project Updates for 6/3/2008

It's been a while since I updated this page. Since my last entry, I made many design changes. First of all, I decided to go with a dsPIC33F device that is specifically designed for motor control. It has many nice features that would make future expansion of the robot very simple. However, in order to use it, I need to have an ICD (In-Circuit Debugger) to program it since making some kind of adapter for my programmer would be impractical and the ICD allows debugging straight from the software, which is very nice. I went ahead and built a USB version of an ICD clone, but when I attempted to plug it into my computer, the lights lit up, but no new device was detected. I compared my circuitboard to the original schematic and found a couple design bugs, which I fixed, but it's still not working at this point. I wonder if I may have fried the USB chip when removing it. I do have another one and I probably should have tried breadboarding this before making it, but oh well. That portion is on hold for now.

Recently this past weekend, I had stopped by goodwill and found a Nikko 4WD car (I can't remember the model) that came without a remote or battery for only $6.99, so I bought it. I am now going to use this for the chassis. It's much bigger than my truck and looks more proportionate to my remote control size. The motor that controls the steering is basically a pseudo servo and has a potentiometer and a motor inside with some gears. I am working on designing a simple circuit that will read the PWM signal and control the position of the motor based on it's value. For that I'm going to use a PICF628A which has all of the basics I need. I should be able to get this circuit working in the next few days, which is extremely simple. I have more to update, but I need to get going.

Posted in Old Posts 03 Jun 2008