PBP projects for R/C models

[Kenjones1935]

I think this video does a pretty good job of showing the potential of this PIC controlled car.

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With the three sensors this car might be able to negotiate a true maze.

What do you think?

Ken

[mackrackit]

Ken,

I think the PIC® drives better than you do

Looks great!!
That should really get the kids interested.

[Kenjones1935]

I need the correct PWM signals to be going to the wheels (Electronic Speed Control) and to the steering (servo) at all times.

I have programmed a PAUSE 500 to guarantee sufficient time for the car to back up out of trouble after hitting a wall.

Am I correct is thinking that since PAUSE 500 is not re-entrant my interrupt driven PWM pulses will not occur for that 1/2 second? The car will not back up as planned.

I need to turn my PAUSE into a time consuming DO LOOP. True??

Ken

[Kenjones1935]

Sorry, folks, I've been distracted trying to figure out how to "kit" this "educational tool" (toy). The Microchip PICKit2 board only costs $23.99. It has a small surface mount proto area. I do not understand how to make use of it. I need to mount my Zettler relay and my TI sn7407n plus a bunch of mini EMS connectors for the radio, the three SRF05's the steering servo and the electronic speed control. sssissshhh!

Today I eliminated the need for channel 3 on the radio system. Which is very good cost-wise. Regular Ready to Race hobby cars come with only two channels on their radios. Adding the third is quite expensive. The PIC can know it is inside a maze given input from three proximity sensors. If there is something close to the right and to the left then it must be in a maze. The first run of this new algorithm showed it flawed. The PIC thinks it is out of the maze when it comes to a corner.

Back to the drawing board. Any suggestions?
Ken

[mackrackit]

Is darkening the maze an option? Then maybe a light sensor would work??

[Kenjones1935]

My first attempts at toggling between PIC and Radio control automatically have not gone well. I figured that the PIC could know from the proximity sensors that it was inside the maze. There seems to be too many variables.

If I were to use a light sensor to distinguish, which sensor and at what wave length makes sense. Remember I am imagining the cars to be racing - going fast even in the maze. This set up would be in a middle school gymnasium - a basketball court maybe. If I could imagine making a maze out of BIG cardboard boxes with roofs I could use simple light detection. But I don't see how to make that elaborate a maze. Is there a light detector that does not see ordinary ambient indoor lighting, but does see some kind of special light source? Could I run a string of these light sources the length of the maze? Inversely I could run a string of these light sources outside the maze where the cars would see them.

Thanks for your attention.

Ken

[mackrackit]

I was thinking a "tunnel" type thing, but now I see that is not going to work. Maybe the light idea is not the way but still on that thought.

Have you seen a "line follower" setup? An IR sensor follows a black line...
What about having the floor in the maze black and an IR looking down on the front of the car?

Or...

A horizontal IR beam at the beginning of the maze and one at the end. Sees IR once the car is on auto, sees IR the second time and it is back on manual.