Hi, i´m starting a new big project, i´m making a new sculpture, i´m trying to connect a 76 dc motor and me xbox kinect. I already setup the kinect and i´m using processing. My questions is, may I connect 4 Arduino DUE in order to use all the PWM ports, or someones have a better idea?
My other idea is group 4 dc motor in only one pin, in order to reduce the number of pins, but i´m not sure if its possible.
The DC motor is 6v. I don´t care know the direction of rotation, using on direction works for me. I dont want to go intro H-Brige know.
If someones have a good idea or something i really appreciate
Better idea is to use some ICs to drive the motors. The Due's 3.3v output only drive a few mA of current.
How much current do the motors need?
You can use ICs with a lot of PWM outputs to drive P-MOSFET transistors to source current to the motors.
For example, WS2803 has 18 PWM outputs with 30mA capability, use that to pull gates of P-channel MOSFETs to turn them on. 1K resistor to 6V to turn the MOSFET off, the WS2803 pulls the gate low with PWM to turn them on.
18 outputs, so 4 chips would be needed. Only place I know to get them is E-bay, I would suggest the seller in Niagara Falls.
And 76 P-channel MOSFETs with Logic Level gates and low Rds (Drain-source on-state resistance) when on, such as:
Datasheet:
The key part being:
Rds-on: V GS=-4.5 V, I D=-9.7 A, 190-270mOhm
This one is even better for a few cents more:
I´m going to use a dc motor 3v witch gearbox reduction. My problem is, i dont know how to conect all of them (76), my firt idea was using 4 arduino Due inorder to try to use all of PWM ports, but i´m not sure. Or should i use a bootloader?
OK, tell us more. What are they going to do, how often, how many change at once, etc etc. If
only a few change at once some sort of I/O PWM breakout board/boards might be enough to get all
the signals out. As for motor drivers I presume winches means H-bridges throughout since you have
to drive both ways.
cpenzo13, which is it? Do the motors only need to turn 1 direction with controllable speed?
Or you need 2 direction with controllable speed?
Sculpture would imply 2 direction in my mind, in & out, or back & forth, or up & down, etc.
That would mean 76 H-bridges. PWM for speed control.
We need to know the current draw on the motor, or better a link to a part number, to make further recommendations, which will likely involve a custom design, or a big mess of off the shelf parts and a mess of wiring.
For example, maybe 38 of one of these dual H-bridge chips with shift registers and other chips providing the control and PWM signals.
I don´t care know the direction of rotation, using on direction works for me.
Do you need to control the speed of motor rotation? If not then a simple transistor setup might be used for on/off operation. Latching multiplex chips probably could be used for control of the transistors.
I would like to use both directions ( but it´s no indispensable ) (I think using H-brige is going to be a little more difficult )
It is should be like the simple project , the next step is to connect the Xbox Kinect to the computer and control all motor with it. (Using Processing and Arduino). I already controlled a few led`s with the kinect, o should not be to difficult to control the motors.
I'm not totally understanding what you want to be able to do here, maybe a drawing of your idea and a few of the motors would help us all to fire off some ideas at you. If all you wanted to do was turn the motors on and off in a single direction, the very easiest way I can think of to do that would be with a transistor. The 2N2222 would be one of the least expensive. You can buy a lot of 100 of them for only a few dollars if you shop around.
I've used this on really low level robots using DC motors to get some level of forward and rotational control. Turn one motor on and you slowly pivot around the wheel that isn't moving, turn both on and you go forward etc. This will allow you to use separate power sources for your motors and your micro-controller. You wire the base of all of your transistors to an output on the Arduino run the emitter to ground and positive to your motor. You can then turn the output HIGH and the motor turns on, or you can control it's speed using pulsed-width modulation. If you want to turn your motors both directions, the best way to do that is with H-bridges. These may seem challenging at first but I assure you, once you wire your first one up and get it working, they're really quite easy. Probably easier than interfacing with your game console.
Here's a schematic I dug out of google in a couple seconds for a basic "On off switch" using a single transistor.
I'm not an engineer so I might not be explaining this as well as I could but this should give you a fair idea.
As for connecting multiple Arduino boards together, can you do it? Sure, using I2C it is possible. I have not done this myself yet, but here's an Instructable that should walk you through it. I2C-between-Arduinos
Brand Name:ystd010
Continuous Current(A):70mA (250mA MAX) (3V)
Usage:Car
Type:Gear Motor
Certification:CCC
Torque:800gf cm min (3V)
Speed(RPM):1:48 (3V time)
Commutation:Brushless
Voltage(V):3V~12VDC
Model Number:28856
If you can live with just 1 direction, then a set of ten TPIC6A595 shift registers, with 350mA continuous current outputs, can be used. Shift in a 1 to turn the motor on, a 0 to turn one off.
Through hole & surface mount versions are available.
For H-Bridge, does this make a difference?
"Commutation:Brushless"
If not, then 38 of a part like this,
with 19 shift registers to control motor direction (each shift register controlling 2 H-bridge chips), could be used.
Why would you use twice the amount of components?
ULN2001A is only 7 channels too. At least recommend an 8 channel part.
ULNs will have high voltage drop across their output - up to 1.6V (likely somewhat less with max 250mA load).
TPIC6A595 will have just tenths of mV (0.25V) drop.
For a 1-time build, I'd go with the slightly higher cost, lower quantity design. 10-lot from Avnet.com would be $2.33 each.
If building lots of these, then lower cost parts on larger PCB boards might be more attractive, unless assembly costs make fewer parts a better option.
Not to derail your intellectual sparring, but couldn't he literally just use relays? He's already said he doesn't need to control speed and doesn't exactly care if the motors turn in both directions. Besides, 76 relays clicking on and off might make an attractive addition to this art piece.
I found a listing for HK19F DPDT relays for 52 cents each, free shipping.