Run a Linear Actuator ?

dc42

That depends on what you want to do with it. If you want to use it as an axis motor, that will be difficult because it needs to be synchronised with the other axes and extruders. If you just want to command it to particular positions using a special Gcode command, that should be possible, using the controller that Pololu recommends for it.

CJ.BRAVO

I want to use it as an extruder - "Tool 0" that will consist of one stepper motor and the linear actuator (mixed ratio).

dc42

@CJ-BRAVO said in Run a Linear Actuator ?:

I want to use it as an extruder - "Tool 0" that will consist of one stepper motor and the linear actuator (mixed ratio).

Do you mean that you will use the linear actuator to do some sort of mixing control, and the stepper motor to do the extrusion? If so, that should be possible. You would put commands in the tool change files to send to the Pololu controller to set the linear actuator position.

CJ.BRAVO

@dc42

Using the actuator to push paste and stepper to move auger screw for extrusion.

the two are in a mix ratio of 1:3 (actuator:stepper) - at least thats what I need.
So I need the actuator to change speed according to gcode in sync with the stepper.

dc42

@CJ-BRAVO said in Run a Linear Actuator ?:

@dc42

Using the actuator to push paste and stepper to move auger screw for extrusion.

the two are in a mix ratio of 1:3 (actuator:stepper) - at least thats what I need.
So I need the actuator to change speed according to gcode in sync with the stepper.

What will you do when the actuator reaches the end of its travel and there is more extrusion to be done?

CJ.BRAVO

@dc42

I stop the print and refill the cartridge of the linear actuator.

setup is a cartridge with paste, pushed by the linear actuator (hopefully), running through a tube reaching to an auger screw that's operated with a stepper motor.

The current setup is using two stepper motors for cartridge and auger but cartridge needs stronger motor with a different setup that a linear actuator might provide.

T3P3Tony

@CJ-BRAVO maybe @tom_lauerman can give some advice about this. he has a setup using a piston and auger i believe. not sure how the piston is moved.

CJ.BRAVO

the linear actuator that i'm fond of (https://www.pololu.com/product/2327) can be controlled by this motor control :
https://www.pololu.com/product/3142

it's mentioned that can be connected with TTL serial and I²C.
So I'm assuming I can get to work with the duet as an extruder?

T3P3Tony

@CJ-BRAVO It will require firmware changes to work as i2c or serial are not used to control synchronised motor axis in RRF.

Less work.woul be to find an alternative actuator.

CJ.BRAVO

@T3P3Tony

I needed it for synchronized extrudsion tool but I reckon it's also a bit of a mess.

So I'm heading back to a stepper motor I guess.

Silly question but can a servo motor synch with a stepper motor to work together as an extruder?