Open Source Stepper Motor Controller Problem Statement

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Revision as of 17:24, 24 April 2011 by Mjn (talk | contribs) (→‎Requirements: Added specs of the Xylotex Nema 23)
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Problem Statement

To date, there is no open source variant of the respected Gecke G540 stepper motor controller. Smaller ones are available for RepRap, but is there an open source option that could be used on a larger device such as the Torch Table Build? The problem statement involves driving the cost of these stepper controllers down to about $10 or so per axis by the ability to mill them on a bootstrapping CNC Circuit Mill. Thus, the problem statement is threefold:

  1. What is the best bootstrapping CNC circuit mill available that could produce not only the stepper motor controller but also the microcontroller (Arduino equivalent)?
  2. What is the best open source stepper controller that can be used, and can it be adapted to higher voltage power supplies that would allow sufficient power to drive a torch table?
  3. If the above is not possible, then we move on to an Open Source Stepper Motor Controller designed from the ground up

See Stepper Motor on Wikipedia for a high level description and a nice animation of how one works.
A Tutorial on Control of Stepping Motors.

Requirements

The stepper motor being considered is the Xylotex Nema 23 Double Stack/Double Shaft Bipolar Stepper Motor. See [1].

Specifications are:

Holding Torque 269 oz.in
Rated Current 2.8A/phase
Phase Resistance 1.13 Ohms
Phase Inductance 3.6mH
Step Angle 1.8 degree (200 spr)
Motor Body Length 3 inches
Shaft width .25 inch
Front Shaft length .75 inch
Back Shaft length .62 inch
Wire lead length ~12 inches

Possible Solutions

A possible solution is to use an existing open source driver option and a CNC mill to build them.:

  1. http://reprap.org/wiki/StepperMotor#Stepper_drivers
  2. Mantis 9 - appears to have a boot-strappable stepper controller and microcontroller design that could be made on this $100 mill. Good points - $20 spindle; $100 for everything. Modify this to metal for stability, and this would make a great universal bootstrapping circuit mill to last a lifetime.
  3. SnapLock appears to be a robust bootstrapping mill, but cost is $600
  4. MyDIYCNC - $580 for complete kit
  5. RepRap Prusa Mendel - simplified version of RepRap Mendel. What's the cost for just circuit milling?
  6. KitsRUs Kit 94 Digital Rotary Control of a Unipolar Stepper Motor
    1. Picture of PCB
    2. encoder.zip Kit 94 source code 2K
    3. ecw1j.pdf Kit 94 Bourn Grey Switch encoder Data Sheet
  7. KitsRUs Kit 109 Unipolar Stepper Motor Driver Kit
    1. Drives any 5, 6 or 8 lead unipolar stepper motor. Based on the UCN5804 IC. All features of this IC (direction, on/off, pins 9 & 10) are brought out to SPDT PCB-mounted switches. Pulses from a 555 setup as an astable oscillator are used to rough position the motor. Switch to manual single-step mode for final positioning using a tact switch. 4 LED's give visual indication that step has been made. Three run modes supported. Full explanation
  8. KitsRUs Kit 113
    1. March 14, 2005. Kits 113 158 179. Peter Simmonds has developed a visual basic program with source code which can interface a PC running windows to the stepper motor kits K113, K158 and K179 via the parallel port. It uses a high speed timer component RSTimer. Both the source code and RSTimer are available for free at here. Two Stepper Motors Driven from a PC. Connects to the PC parallel port & will drive two stepper motors up to max. 3A each. All contained in an RS232, extended D-shell case. Software will accept 4 inputs from external switches. Software will also single step motors. Three run modes supported. All components supplied except the stepper motors. This kit uses a Grey switch aka bit switch, to single step a unipolar stepper motor in either direction. Uses a PIC 16C54 plus UCN5804 stepper driver IC. PCB is 4 in square, single sided.
  9. KitsRUs Kit 158, Bi-polar Stepper Motor Driver kit
    1. March 14, 2005. Kits 113 158 179. Peter Simmonds has developed a visual basic program with source code which can interface PC running windows to the stepper motor kits K113, K158 and K179 via the parallel port. It uses a high speed timer componentRSTimer. Both the source code and RSTimer are available for free at here
  10. KitsRUs Kit 187 Stepper Motor Drive
    1. The Stepper Motor Chopper Driver is a Bipolar Stepper Motor Drive with easily adjustable current control up to 2A, based on the SGS-Thompson L297 and L298 stepper motor controller and driver IC’s. Stepper motors are rated by current and and not by voltage. A chopper driver because it is switching on and off current allows a set current to be fed to the coils and not be dependent on the voltage of the power supply. The Chopper Driver also allows for the use of higher voltage power supplies (up to 36V) to overcome the effects of the inductance of the coils giving better performance and a higher top speed.
  11. EasyDriver Stepper Motor Driver
    1. Here is a simple motor controller for $15.25 at Electronics 123. Fully assembled, no less.