Servomechanism
with elastic torsion shaft

Controller design with Sysquake and Calerga VR

Virtual Experimentation

Run  

Observe the system to get a basic understanding of its main features: the DC electrical motor is on the left, the load (a heavy wheel) on the right, and both are linked with an elastic shaft. Then interact with the system:

• Drag a point not on the system to move the point of view around the system. You can revert to the initial view with the target icon , and restart the simulation with the reset icon .
• Drag the wheel to make it rotate. Observe the measured values.
• Drag the square blue handle left and right.
• Compare the system behavior when the handle is on the left (it becomes red) or not. Do you think the model structure is the same? Why?
• Press the yellow button (second button from left) to apply a voltage of 2 V and observe the measured values. Brake the wheel by touching it. Touch the wheel at a point closer to the rotation axis and compare the effect.
• Move the wheel left and right and observe what happens.
• Press the small triangular arrows next to “1/3” above the measured values to switch the display. The second display shows the controller parameters used in feedback controller mode; the third display shows a scope with the measured values. Move and release the wheel. What can you observe on the scope?
• Press the red button to halt the system. Press it a second time, a third time, rotate the wheel by hand or by switching one or two seconds the yellow button. Observe what happens.
• Press the gray button (right-most button) and observe what happens.
• Press the green button to switch to the feedback controller mode, with gray button off. Observe the measured values until the rotation speed of the wheel is constant.
• Brake the wheel until the rotation speed becomes constant again and observe what happens. How is it different from the 2 V constant input?
• Experiment more in controlled mode. Is it a good controller? Why?
• Pause the simulation by unselecting the “Run” checkbox.

Model

For simulation and controller design, the system is represented as a state-space model.

Details

Controller design

The transfer function from motor input (voltage) to wheel velocity and a controller based on it can be computed with Sysquake.

Sysquake js