How do I give a radio control car autonomous control

[Kenjones1935]

I am trying to modify a 1/10 scale RC car to carry a microcontroller with the capability of taking over control of the car. The idea is to hook middle school students into Science, Technology, Engineering, Math by creating a vehicle that can perform both under RC and autonomous control. Controlling the servos and the motors is nothing new. I have found nothing of the interface between the radio control receiver and the microcontroller. Anybody have some suggestions?

[ScaleRobotics]

Here's a simple pulsein example for reading what the receiver is sending the servo's:

http://www.picbasic.co.uk/forum/showthread.php?t=12039


And I used the RCAP pibasic pro based autopilot on an rc plane. I know a few people that have used it to control RC cars. This requires a GOTO gps (like handheld garmin, etc). But for extra credit, the cordic could be used to determine the distance and direction from one waypoint to another ... that is, if gps was in your plan.

Some info, and the picbasic code can be found here:

http://en.wikibooks.org/wiki/RC_Airplane/RCAP

Walter

[Melanie]

Define your vision of 'autonomy'.

When I was a little girl, a favourite uncle of mine gave me a toy electric car for Christmas. It had one switch ON/OFF. Switch it on and the wheels drove forwards in a straight line until it hit an object. On impact, the polarity to the motor was then reversed for a couple of seconds, but because of the central front wheel (it looked like it drove on four, but the two visible front wheels were actually dummy) was housed in a curved slot, when driven backwards the car would swing to the left. The polarity would then switch back and it shot off forwards in a new direction. In this fashion it could travel all round the room - completely autonomous - until the Batteries went flat or you switched it off.

[Acetronics2]

Hi, Mel

Pretty good question ...

let's suppose the model must stay on a 1/10 scale winding road ...

... As it was in the Beatle's song ... a long and winding road.

Precision of a GPS can be enough for a plane ... but a model car ...

Alain

[ScaleRobotics]

You are right, you need a wide road for the RCAP as it is. And no, it is not autonomous, but it includes many of the items that Kenjones1935 is asking about, like an example of a connection to the receiver that allows either transmitter control, or switched to "autopilot" mode, where the pic controls the servo. But I would love to see more examples as well!

Here is 4 or so trecks down a the straight, wide (1/1 scale) roads. Another good place would be a soccer field.

[Kenjones1935]

Thank you all for your encouragement and suggestions.

My vision is a car that can be raced using the regular RC control on a circuit defined in the basketball court of the middle school gym but then the track leads underneath the fold down bleacher seats. The student running the RC can not see under the stands. Remember that under there on the floor are many supporting structures. The car must avoid these on its own.

A different vision is to have the same track on the gym floor, but including a maze made from, say, cardboard boxes that the car must navigate. We could put Xmas tree lights over each of the exit holes in the boxes. In autonomous mode the car could sense the lights.

RC cars have beautiful model suspensions. They go very fast and are quite indestructible. From the point of view of developing STEM thinking they are missing a formal language and repeatable controls. I are trying to marry the two.

Ken