DIY 2DOF build project

Hi everyone!

I have an on going project where i'm building an 2DOF simulator.

The simulator was designed in CAD before ordering parts.

The parts I'm using are:

Motors:


Model: 5D120GN-RV40
Number of poles: 8
Rated power: 120W
Rated voltage: 24 (V)
: 1800rpm
Current: 7A
Wormgear ratio 1:30
Torque: 12,5 Nm

Electrical components:

Arduino UNO running SMC3

VNH5019 2 channel 30A motor driver board.

Power supply 24V 16.5A 400W

5K Ohm potentiometers


The electronics were connected and the motors were tested in SMC3.


Parts for the frame was ordered/manufactured and partially assembled.


This is the current state of the project


I have tested the simulator with simtools and the axis/DOF seem to be correct.

The problem I'm having is that the motors are jerking/juming a lot.
I'm suspecting that the motors are not powerful enough or not mounted in the optimal position.
If you have any suggestions/tips please help me.
I'll keep you updated.

Thanks!

I think my rig is pretty well balanced, but I will try to balance it again.

Resting angle is 90 deg.

Simtools settings:



SMC3 settings:

I've tried different values for PWMmax and PWMrev.

I also downloaded SimCalc and entered my values, the forces seem pretty low right?



I will try to film the rig the next time i'm testing it.

Also bought myself a Christmas present, can't wait to try it with the sim.

Enjoy that wheelbase! I have the same one and it is really fun to use.

Like noorbeast said, you should refine the motion profile when you want to test the motors. For example I have my axis allocation at 25%.

Did some testing today. It seems that the problem is not in the Simtools settings, I have the same problem when testing the motors in SMC3.

I took some screenshots in SMC3 and a video to show you what's going on.

This is the curve on PWMmax 90 and i slowly manually moved up and down:

This is the curve on PWMmax 120 and i slowly manually moved up and down:


I tried disconnecting the rods from the motor and still saw the same kind of pattern.

PWMmax80, not connected to rig:


PWMmax40, not connected to rig:


Here is a video from the tests:


As you can see from the curves/video when the motor moves down the PWM curve spikes/jumps up and down and the motor shakes, same problem can be seen even with the rods disconnected. This happens for both motors.

Ah, I have had this same exact problem with my simulator. The solution for me was to use the Ziegler Nichols method.

You tune one parameter at a time and it will ensure smooth movement.
Let me know how it goes.