andales

Can anyone help me with a project?

I was thinking about interfacing a toy car to a computer port and then control the toy car's motion using keyboard input and using Visual Basic Program.

If I press the up arrow key the toy car will move forward If I press down it will move backwards, left if I press left arrow key and right if I press right arrow key.


Please help me

Sincerely,
andales

3v0

Are you open to what type of computer port to use ?

It would be best to put a micro controller in the car. You will also need h-bridges to convert the control signals to levels that can run the motors.

It will be a lot of learning and fun (some misinformed would call it work) but it can be done.

The printer port could be used and would not require a micro controller. But you would have that massive cable to deal with.

Are you still interested ?

Hank Fletcher

I'm just guessing here, but I think those micro R/C cars have controls that are just switches (i.e. full left, full right, full forward, full reverse). I think it's the same deal with cheap R/C toys, with the exception of maybe a pot control for the throttle?

So to make it work without having a cable tethered to your computer, and with the least amount of parts, I'd say hack the R/C controller. Use the parallel port and interface that with the controller: transistors or h-bridges for the switches, and a programmable resistor for the pot.

Voila! Seems like an awesome project - good luck!

andales

yes of course. I am still interested. I will be using the parallel port. so What should be the configuration of the wires of the cable?what devices I shoould use?Do i need to use Max 232? can i have a schematics if possible?

Hank Fletcher

The design and parts you need will largely be dictated by what you have to begin with, and what your plan for hacking the toy is. You don't need a MAX232 to interface your parallel port with anything (the MAX232 is for serial ports). The output (and input, if you want to program some sort of feedback into your toy) from the parallel port will be fine as it is. Read up on the parallel port if that's what you're going to use:
http://www.beyondlogic.org/ecp/ecp.htm

What's the toy car you're using? I still say hacking an existing R/C toy is the best way to go, but maybe the toy you have doesn't even have R/C to begin with? Even given the extra work it would take, I'd highly recommend adding an R/C component to your design over trying to plug a parallel port cable directly into your toy. How fun is that going to be, dragging a thick cable a whole three metres (because I don't think the parallel port is good for much longer than that) across your desk?

3v0

RC would would be an improvement. IFF you do not want to go with RC

They used to sell toy cars and such with a remote that was connected to the toy with wires. To use one of these you would just replace the mechanical switches with transistors or relays controlled by the port.

andales

I was thinking about two kinds of toy cars, the bounded and the radio controlled toy cars. First I want to be able to control the bounded type and then the Radio Controlled.

Can you give me all the information includin schematics and VB source code?

Hank Fletcher

Would if I could, but for starters I've never used VB (I use Liberty Basic), although I know many have successfully (and I'm presuming fairly easily) used VB to send and received parallel port signals. Read up on the parallel port in VB, the parts of the port in the link I posted, get some LEDs, and start trying to send some signals through the data port. Word of advice: be sure to set the data port for sending rather than receiving signals before you connect your LEDs.

The other reason I can't give you all the information you need is because I have no idea what you have to begin with. Get a cheap RC car, take it apart and put it back together again. By the time you've done that and read up on the parallel port, you should have all the answers you need.

ericgibbs

hi,
Look at this zip, it will give you an insight to the parallel port, theres also some of my VB source code you can use.

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

andales

Can you give me the schematics for it?

I have bought two types of Toy cars. One is bounded and the other is wireless.

So how do I replace the mechanical switches with transistors or relays controlled by the port.? Can I have schematics?