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Which product I should buy?


#1

Hello folks,
I have a large Bipolar stepper motor with rated current (parallel wiring) of 6 A and recommended voltage 30 VDC. it can be found here https://www.phidgets.com/?tier=3&catid=24&pcid=21&prodid=355
and rotary encoder with supply voltage 5 VDC which can be found here https://www.phidgets.com/?tier=3&catid=4&pcid=2&prodid=404
and I will buy a servo motor with operating voltage (6 to 7.4 VDC) from Pololu which can be found here https://www.pololu.com/product/2375/specs

After some reading in electronics and micro controller I think I should buy the following boards to control these motors from MATLAB

1 - A-Star 32U4 Prime SV microSD
2- DRV8825 Stepper Motor Driver Carrier Or Tic T825 USB Multi-Interface Stepper Motor Controller
3- Mini Maestro 18-Channel USB Servo Controller

I am a mechanical engineer and doing experiments in aerodynamics.Most of the motor motions I am interested in are harmonic motion such as this equation Like α=10 (degree)+10 (degree) sin⁡(ωt) α is the angle of the motor shaft
so my questions are :

1 - Are these boards selections correct to control both motors and to receive signals from the encoder? can I connect the stepper controller and the mini Maestro at the same time to the A- Star microcontroller?
2 - Is the A-Star seen by MATLAB as Arduino UNO I mean with the same Arduino commands?
3 - Can I replace the A star with Arduino UNO? is there an advantage for the use of A-star instead of Arduino Uno for my case?
4 - what are the accessories needed to wire all of these boards?
5- I prefer to use a power supply device not batteries, Do you mind if recommend an affordable one?
6 - I need to couple a 6 mm shaft to the chosen servo motor shaft but I could not find a coupler for the 17 teeth spline of the servo like the ones offered buy servocity website? Do you have some idea if there a 17 theeth spline adaptor for this servo or any other way?
7 - I dont have a good experience with electronics so ,is it easy to use the stepper controller or the stepper driver with the A-star board without the need to use additional electronic components?
8 - is the A star board capable of reading data from force transducer like this one http://www.ati-ia.com/products/ft/ft_models.aspx?id=Gamma?


#2

Hello.

It’s probably not very practical to use the Phidgets stepper motor you mentioned with any of our stepper drivers. That motor uses more current than any of our stepper motor drivers can provide so the torque available from the motor would be well below its potential.

The Arduino Uno and our A-Star boards have a lot of similarities, however there are some specific differences between them and, in general, we cannot say which might work or be better for your application. You have several questions about interfacing other boards and one specific difference between the Arduino UNO and our A-star boards that might be relevant for your application is that the ATmega328p microcontroller the UNO uses only has a single hardware serial port it can use to either talk to a computer over USB (like you mentioned for MATLAB) where the ATmega32U4 microcontroller the A-Star uses has a dedicated internal serial port for communicating over USB and an additional hardware serial port that can be used for a hardware peripheral like the Maestro.

To determine whether any combination of other devices might work with your microcontroller board, it helps to think about how each device connects to the microcontroller and to look for potential conflict between those connections. For our DRV8825, we provide a Minimal wiring diagram on the product page for the driver that shows a minimum set of connections. Our Maestro user’s guide and Tic user’s guide (both linked to on the “Resources” tab of their respective product pages) document the connection interfaces available.

It sounds like the devices you want to use will require a range of different voltages. You can find our AC power adapters (which will allow you to get low voltage DC power from an AC mains plug) and our voltage regulators (which can convert from one DC voltage to another) in the Regulators and Power Supplies category on our site.

We do not know of any 6mm shaft couplers for the servo you mentioned.

-Nathan


#3

Thanks for your reply Nathanb.
it seems I have to use the phidgets controller for the large bipolar stepper motor. Does the mini maestro read data from potentiometer for feedback control of the stepper motor as the phidgets stepper controller doesn’t have input to read from the potentiometer?


#4

The Maestro can read analog values like those a potentiometer might produce but it might not be very practical to control that Phidgets controller with the Maestro. An Arduino-compatible board like the UNO or the A-Star 32U4 you mentioned before should also be able to read values like that.

-Nathan