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reposting >> need help to find a motor controller

Posted: Mon Aug 31, 2015 3:10 pm
by dacflyer

Re: reposting >> need help to find a motor controller

Posted: Wed Sep 09, 2015 7:26 pm
by cae2100
why not just build your own, a simple 555 timer analog to pwm generator would work perfect for you, add another and some mosfets, and you have a 2 channel analog motor driver.

Here is an example of analog to pwm converter using a 555 timer. If you used a 556 timer, you have two 555s in the same package to size down the circuit quite small.
http://www.circuitdiagramworld.com/basi ... 14413.html

Re: reposting >> need help to find a motor controller

Posted: Thu Sep 10, 2015 7:08 am
by dacflyer
i looked at this,, it does not seem to have the ability to for a signal to reverse the motor.
and if i was to use a joystick pot, would it be at 0volts when the stick is centered ?
these are the issues i am facing.. have done 555 PWM etc. before, but not in this fashion.

Re: reposting >> need help to find a motor controller

Posted: Thu Sep 10, 2015 6:11 pm
by cae2100
hmmm, only thing I can think of is to do two sets of the circuit and set each one in an H-bridge pattern, then it could be reversable and such. Another thing you can do is just use a simple microcontroller to read the value of the pot throught an A/D pin, I use it all the time to tell the values of thermistors, just a pot would be centered around 128. minimum is 0 and max is 255, just tell the microcontroller to read that and turn it into pwm on two pins depending on what side of 128 (middle) it is. That is really all you need, most arduino motor shields can control at least 2 motors and sound perfect for what you need.

Here's an example of what Im thinking of:
http://www.instructables.com/id/CRANE-GAME/?ALLSTEPS
Looks like the code and everything that you are really after is right there also.

Going that method with the arduino isnt really that expensive imo, you can easily build the motor shield yourself on some breadboard and the arduino clones, you can find for like 10 dollars. The clones are good to play around with to learn off of, but genuine arduinos have a bit more hardware tweaks that make them a bit better. The motor shield, the older one used l293d but thats only good up to i think like 500 mA per channel, the SN754410 handles a little bit more if you wanted to do the h-bridge stuff with just a single chip. They both pretty much have the same pin layout and such so is interchangable as far as I remember.

An alternative to that is just make your own h-bridge with just a few mosfets and switching transistors. Makes the board a little bigger, but you can push alot more power through it and later upgrade to larger motors and can adapt your design to fit your needs.

Re: reposting >> need help to find a motor controller

Posted: Thu Sep 10, 2015 7:13 pm
by dacflyer
i have a UNO, but i am not good at code at all, can a smaller micro be used? i have seen some really small ones ( arduino )

i found this at the flea market this weekend, i can't find much info on it, but i know it was part of a university project
this is the info on the board.. i seen on the satellite board there is a dual H-bridge on it.
QSK62P PLUS Rev C
and then it has on the satellite board. ECE306 NCSU the project looks like it was part of a line follower robot
i bought the board and what was left of the line follower for $1.00 :D
so maybe if there is a way i could use the satellite board in some way.. or would it just be cheaper to find a small micro with built in H-bridge ?

i have found this small 5A h-bridge board
https://www.servocity.com/html/roboclaw ... fI1Tpd8ctE
but it is way out of my price range. ( $70.00 + S/H )

would this be usable ? http://www.adafruit.com/products/2377
i think i could easily attach pins from that to the section of this satellite board, unless there is a micro H-bridge board out there somewhere.

i hope i am not making this more confusing than it needs to be..

Re: reposting >> need help to find a motor controller

Posted: Thu Sep 10, 2015 11:21 pm
by cae2100
from what I can see, the main board you bought was just a large microcontroller board, a kind of trainer for the electronics, the satellite board, I tried looking it up to find a datasheet, but it was part of the college there as a class name, other than that, everything else I found was that they're kinda tight lipped about thier stuff other than the videos. I would try to see if there is any other numbers or anything on the satellite board, and just keep googling everything to see if you can find some sort of datasheet. That should allow you to hook it up if Im not mistaken quite easily after you get the pinouts.

The motor controller you have there is pretty expensive, I have to agree with you there, I usually just build my own boards and saves me alot of money that way. Just build it out of trash and you'll be set, lol. All you really need is just the mosfets and board. Look on ebay and you might be able to find either the mosfets and everything, or you could find a pre-build board on there if you dont mind the shipping from china.
Here's an example of one of the board Im talking about:
http://www.ebay.com/itm/New-L298N-DC-St ... 2ca0adcc05

As for the arduino, most electronics that you find is 5v logic level components, and if you tried mix matching them, it'll fry the 3.3v stuff, better to go with a 5v version. I have the 5v version of that modeled off of the arduino leonardo, which has built in usb, so you dont need to have a seperate usb converter like the one you listed. I believe it was called the leonardo pro micro, and the code for the normal arduino will work with the leo version with little to no modification of the code, and it is 5v tolerant.

Re: reposting >> need help to find a motor controller

Posted: Fri Sep 11, 2015 5:10 am
by dacflyer
thanks, i'll dig into it more and see what to get, and i'll check back with you and get your advice,
might need help with code also, not sure if you can do that or not, but i would not think it would be too hard if it is just a pot to control a motor forward and reverse.

my ideas is to use a old R/C joystick..
the more the stick is moved the faster the motor would turn, and center position would be stop
opposite would be a reversed move.
i think you get what i am going for.. but ultimately this will all be for a wired PTZ pod for a camera for use on my plane,

Re: reposting >> need help to find a motor controller

Posted: Fri Sep 11, 2015 7:19 pm
by cae2100
yea, the code on that instructable for the crane would work exactly for what you are after, just change the pins in the code to match your needs. Thats what it does.

Re: reposting >> need help to find a motor controller

Posted: Sun Sep 13, 2015 12:13 pm
by dacflyer
cool,,thanks, i'll look into it.

Re: reposting >> need help to find a motor controller

Posted: Thu Oct 29, 2015 10:24 am
by ReidLage
There are many motor controllers available. H-bridge is also a popular one. I want to know about your motor specifications.
Which type of motor is it and what control you want with it?
Also you can build your own by using a simple 555 timer analog to pwm generator and some mosfets, and you have a 2 channel analog motor driver.

assembly card circuit

Re: reposting >> need help to find a motor controller

Posted: Fri Oct 30, 2015 1:39 pm
by dacflyer
well i am looking into a "H bridge" really does not matter as long as i can get 2 directional drive.
the motors i am using are modified servos, brush type motors.
the servos have the electronics stripped out of them, and the stops cut out.
i am wanting to use a joystick X-Y 5k pots and the center position is off.. one direction is forward, other direction is reversed.
when i let go of the joystick the motor stops. i do not need it to return to a home position.
the motors will use very little current. less than 1 amp. and i can use wither 5 or 12 volts.