Programmable Potentiometer/Resistor For 12V DC Motor

[Arouse1973]

Ok so I think we should start with the interface side of things, because we may not need to design a motor driver if we can get an off the shelf one to work. We need to nail down what socket control method you are going to use, USB, or serial. My first offering is for serial connection. Lets forget the PC GUI interface for the moment because you might want to as @hevans1944 mentioned use a phone or something.

So we could use this http://www.robotshop.com/en/8x-12-bit-digital-to-analog-converter-pmodda4.html to take an instruction from the application software and convert it to a voltage, to control one of these http://cds.linear.com/docs/en/datasheet/69921234fc.pdf.

Then output that into an off the shelf ESC. You will have to make sure the frequency you choose is compatible with the ESC.

To communicate to the DAC you could use something like this.

http://katalog.municom.info/product_info.php?products_id=6979

The user interface could be a little VB app (activeX control) to take data from Excel spread sheet containing your graph and output it to the serial port.

This hopefully will give you some ideas. But you may want to do something different or improve on it.
there are many other options and hardware modules available, this is just an example.
Adam

 

[Scotty Rienschield]

Ok...I am quickly realizing how in over my head it appears I am with this. I like all of this...but where do I start?

 

[Martaine2005]

Ok...I am quickly realizing how in over my head it appears I am with this. I like all of this...but where do I start?

Sit back, buckle up..Gonna be a bumpy ride..
@hevans1944 I still have the original 'You Steer' 1/32nd set.
Slot car or 'Scalextric' has never been out of fashion, just moved to a fanatics corner.
I am not a fanatic but a small time collector. My car collection in it's hundreds is small fry for the real collector.

Martin

 

[Alec_t]

Here's the basis for another option, providing your motor is a brushed DC type :-

Any PC, tablet or phone is used to generate a suitable programmed sequence of different tones. This circuit receives a tone as a line-level input. Each cycle triggers a monostable circuit (U1a, U1b) giving a fixed width output pulse. The pulse turns on Q1 which acts as a level-shifter. Q1 controls gate-driver Q2,Q3 which in turn switches MOSFET M1 to switch on the motor. The higher the tone frequency the more pulses of current the motor gets per second, i.e the greater the duty-cycle, hence the faster it runs. Think of it as PWM with a varying frequency.
With component values as shown, tone frequencies of about 500Hz to 10kHz result in a duty cycle of about 10% to 95%.