PCFormat Forum Archive

Right, so I went scratching through my stepper motors the other day wondering what to use them for.

I have an idea, it won't happen over night though.

What i want to do is build a small robotic vehicle and use stepper motors for the drive train. I'll use hybrid motors for this purpose because I have 2 matched ones from a photocopier

Motor controllers and guides can be found here:

http://www.aaroncake.net/Circuits/stepper.asp Easiest
http://www.instructables.com/id/Easy-to ... Driver-ci/ Part of some other project
http://home.cogeco.ca/~rpaisley4/Stepper.html
http://hobby_elec.piclist.com/e_step.htm
http://zone.ni.com/devzone/cda/ph/p/id/287 Explanation to the coils
http://en.wikipedia.org/wiki/Stepper_motor
http://www.solarbotics.net/library/pdfl ... torbas.pdf More on their operation

However, rather than do everything through a PIC or several pics, I want to control it from a ultra small PC board such as an EPIA running say windows in the background.
then all the sensing would feed into the board for processing and it would then output back to the drive circuitry and it would be fairly easy to upgrade and expand and monitor location, battery levels, etc.

Do anyone know anything about inputs and outputs to a PC for a start?. I assuming I'd have to go through the parallel port?
I still need to try out MS robotics Studio and see what i can do on it and how much programming i need to know.

If I can get the basic framework running, then onto it, I can explore tracking it via say, google maps or adding in a GPS card.
Innitial sensing would be for avoiding obstacles. If i use that first circuit, i can use PWM and count the pulses to track the number of rotations for the motors and their speed which will simplify it alot.

So, comments or guidance would be appreciated.

hmmm ive also been wanting to work on a project like this...............

i had some stuff on which pins do what (on the parrell port ill see if a can find it again) but you will probably need to get extra ports (depending on how many motors you want to run)

you could use optical sensors for the measuring rpm (with the little disk thingy with slits in it)

i had a litle one of those cybot robotics kits. still got the ultrasound sensors and some of the circuitry if you want to have a look (doent help much since you want to run it through a pc but anyhow)

i had a book on robotics and ive lost it................ so i will do a bit of googling for you.


i want to see your design for it

I found some more links between studying and a serial driver design for stepper motors. Will probably use that

i have a working cybot which i'd prefer not to destroy and ultrasound cans are cheap. Like 14 rand per unit. Getting them to generate useable information is more difficult.

Oh and depending on how you step the motor, you don't need a feedback sensor. track the steps and convert to degrees and and the radians

Prime wrote:I found some more links between studying and a serial driver design for stepper motors. Will probably use that

i have a working cybot which i'd prefer not to destroy and ultrasound cans are cheap. Like 14 rand per unit. Getting them to generate useable information is more difficult.

you could use infrared sensors instead?............or just a simple trip switch with a slightly extended arm

djwez wrote:

Prime wrote:I found some more links between studying and a serial driver design for stepper motors. Will probably use that

i have a working cybot which i'd prefer not to destroy and ultrasound cans are cheap. Like 14 rand per unit. Getting them to generate useable information is more difficult.

you could use infrared sensors instead?............or just a simple trip switch with a slightly extended arm

i was planning to use ir later for interaction with a living world. That way you could pick up people and animals in your environment.

i don't know if you can navigate reliably with ir

btw what are you planning on using it for?

Prime, roombas use IR for navigation

http://www.avrprojects.net/index.php?op ... &Itemid=57

Monty, Link?

Prime, the parallel port has a 8 bit data bus on it which you can address. You will have to build some type of interface board for it to control the motors and I would suggest you use some small micro that just interprets commands and then does a necesary action. That way you don't have to worry about blowing up your serial port. Also use a USB to parallel converter (which you modify) and you can get up to 500mA out of the USB port. The other, BETTER option is to use a serial port to talk with said interface board and send commends via RS232. and YES it still is considered direct controlling in my world...

Robotics are awesome. I have been planning a UAV for quite a while now but never seem to get the time to start on it. I will eventually though, might make it into a masters or something.