How do I give a radio control car autonomous control

[Kenjones1935]

More details.

Originally the pulse width modulated signals from the radio receiver control the steering servo motor and the amplifier (speed control) which drives the DC motor.

My design has the PIC interrupting that service by controlling the multiple double pole double throw relay switches.

Channel 3 from the radio receiver be used to tell the PIC to toggle between autonomous control and radio control. This decision can be overridden with the toggle switch in the middle of the picture.

Once in autonomous control the car has two means of evaluating its environment. A narrow angle lense (the cardboard tube from a toilet paper roll?) light sensitive device and two sonic range control devices.

The light sensor could find a incandescent light bulb. Once found (by turning in a 360 degree circle for example) a simple line following algorithm should lead the car to the light source.

The front and right side mounted sonic range controls could guide the PIC counter clockwise around the inside of a room. This idea is on the WEB at:

http://letsmakerobots.com/node/928

Thanks all,

Ken

[Kenjones1935]

A quick judgment please.

I just discovered solderless breadboarding. Does it work? Is it reliable? I think I can buy some at You Do It tomorrow. Is it a good idea?

Ken

[Pic_User]

A quick judgment please.

I just discovered solderless breadboarding. Does it work? Is it reliable? I think I can buy some at You Do It tomorrow. Is it a good idea?

Ken

YES! YES, for most prototypes Yes, they are a great way to test ideas.
-Adam-

[mackrackit]

Took a quick look at the schematic and you will need a regulator from the 6 volt battery pack...

As for the bread boards.
Good, bad, and ugly....
That is all I use for proto-typing. Then when I am happy with things I get the soldering iron out.

[Kenjones1935]

Folks,

OKAY: Details.

My reading of the PICkit 2 Users Guide tells me that AN0 is connected to the on board potentiometer. AN1 is available for my use.

I need to connect the light sensitive resistor to an analog to digital converting input. Please confirm that I am getting this correct.

Pin 20 is A to D input AN1 and available.
It has an input resistance of at least 1Kohm
I can choose my reference voltage to be either Vdd or Vss.
I would install a 1Kohm resistor from Pin 20 to Vdd.
If I were to choose a CDS cell that varies from 1Kohm in darkness to 24Kohm in bright light do you think the A to D on pin 20 could discern the difference?

Yes, a voltage regulator on the six volts. Thank you.

Ken

[Kenjones1935]

A 5 volt regulator has been suggested. I need to know the power requirement.

I have looked but not found the Microchip spec of the current consumption for the PICkit 2 or for the 16F887 chip itself.

Do you guys know where to look or know the value off hand?

Ken

[Kenjones1935]

Anybody know what happened?

[mackrackit]

A 5 volt regulator has been suggested. I need to know the power requirement.

I have looked but not found the Microchip spec of the current consumption for the PICkit 2 or for the 16F887 chip itself.

Do you guys know where to look or know the value off hand?

Ken

I am not sure if there is any one answer. It would depend on the work being done by the chip. ~~How many things and at what current is the PIC driving? LEDs for example.

But saying that..... 1 amp should do for the regulator specs.

[Kenjones1935]

The undisturbed connection between my Fatuba receiver and my ESC box has three wires, black, red, and blue. The black is GND (reference), the red is Vcc (hopefully a regulated 5volts), the third is the signal from the receiver to the ESC telling it which direction and how fast to spin the wheels (what voltage and which polarity to feed the DC motor.)

This is pulse width modulation. How is this information encoded?

My guess is that a square wave (50% Vcc 50% reference) tells the ESC to not power the motor at all. A larger than square wave pulse stream says to feed the motor positive voltage proportional to the area under the pulses. A smaller than square wave pulse indicates to reverse the voltage polarity and feed power inversely proportional to the area under the pulses.

Am I close enough for government work?

Ken

[Kenjones1935]

I bought a Radio Shack 2 1/8 inch IC breadboard socket kit. It looks just like one in your picture.

I am confused on how to use it. I have some dtdp switches that are dual twelve pin packages. They snap into the breadboard just fine, but not over the channel. Hence (if I understand which pins are connected to which correctly) the opposite pins are shorted to each other.

I have a dual inline socket into which the dpdt switch fits fine. It fits bridging the channel of the breadboard. That is what I expected. However, the pins do not snap into place. They are not allowed to become fixed. Could they be too big? I thought everything was standardized.

Our Radio Shack stores are down in inventory and the sales folks know nothing about these pieces.

Ken