PBP projects for R/C models

[Kenjones1935]

Here's a video of our car running a hall in our house.

http://video.yahoo.com/watch/7164676/18657928

I moved the front sonic sensors closer to the front of the car and I figured out how to slow down the wheels a bit.

Next thing, I think, is to build a better looking and stronger prototype using a car with more room to attach stuff. What other kinds of sensors should I try and what other kinds of tasks will they help the PIC do?

Again, thank you for all your interest and help.

Ken

[mackrackit]

Looking good Ken!

Other sensors...
IR - Probably not do much better than the sonic, but they can be setup to "see" light and dark colors. Line follower. Maybe see the white wall...

Hall-effect - Have the car find and park or something on a metal plate, magnetic.

Solar cell or photo diode - Light seeking. You mentioned this at the beginning.

RFID - Place RFID tags along a path and have the car follow. (never done that myself)

[Ioannis]

Consider using PID control for your motors. This way your car will be less nervous in is reactions. Look for the routines by Henrik Olson at http://www.picbasic.co.uk/forum/showthread.php?t=5874

Ioannis

[Kenjones1935]

There is a large world wide subculture of robotics. Does it have a common higher level language? Are there some PIC's obviously better suited for certain kinds of sense and control tasks than others? Where can I read about such things? (I get SERVO magazine. I shall look more carefully for leads there. But where on the WEB?)

Ken

[Ioannis]

Maybe C is what you mean?

I think it's all in the software. Meaning the programmer.

Sure a dsPIC may do better in signal processing or faster, but requires that the programmer can code in C or assembly.

But generally speaking all micros can do more or less all sort of things.

Did you look at the link I posted? I think isthe key to your nervou problems. PID does just that.

Ioannis

[Kenjones1935]

This video is the same as the previous except it has an additional segment. The car goes down the hall, turns around and comes all the way back to me!!

http://video.yahoo.com/watch/7169550/18673820

Ioannis, I agree a potentiometer driven by a servo controlling direct current into the wheel motor would give the PIC smooth speed control.
For this home project with only my personal resources that is a complication I hope to avoid.

I would like some help directing me to a way to make interrupt driven PWM pulses delivered 50 times per second. My impression is with PBP GOSUB does not include arguments. This is very restricting. Am I correct?

Ken

[Kenjones1935]

I saw an article in SERVO which speaks about the VEX robotics computer package. The PIC is a 18F8520. My impression of the Microchip PICkit3 is that it is very close - it has a 18F8722 and a 18F87J11. The cost of a complete PICkit3 is only $164.00. Would using this tool make my project easier? more robust? more powerful? more flexible?

Ken