I want to generate encoder output pulses from the angular velocity of a motor using simscape.

I want to reproduce the A and B phase pulses of the encoder using the Incremental Shaft Encoder in simscape's Electrical. The angular velocity of the motor has an output signal in another model and I don't know how to connect it to this simscape encoder.And it is not clear how to get phase A and B signals as simulink signals.

Answer 1

[Sreeram]

Hi @滉 中桐,

I see that you have connected an Ideal Rotational Motion Sensor block to the Incremental Shaft Encoder. Ideal Rotational Motion Sensor is a device that converts an across-variable measured between two mechanical rotational nodes (R, C) into a control signal proportional to angular velocity (W). It is a sensor and cannot be used as a rotation source for the Encoder. Instead, you can use an Ideal Angular Velocity Source. This block generates a velocity differential at its terminals (R, C) proportional to the physical input signal (S).

You can pass any Simulink signal, such as a sine wave, to the port S of the Ideal Angular Velocity block through a Simulink-PS Converter block.

Regarding the second part, the output signals A and B are voltage signals. They need to be converted to physical signals using a Voltage Sensor, and then the physical signal can be converted to Simulink signals using a PS-Simulink Converter block.

Here’s how you can make the connections:

1. Connect the Simulink signal to the Ideal Angular Velocity Source using a Simulink-PS Converter.
2. Connect the output of the Incremental Shaft Encoder to the positive terminal of the Voltage Sensor. Connect the REF signal to the negative terminal of the Voltage Sensor
3. Use a PS-Simulink Converter to convert the physical signals (V) from the Voltage Sensor to Simulink signals.
4. Visualize the signals using a Simulink Scope block.

Here is my connected model for your quick reference:

Do not forget to add Solver Configuration and Mechanical and Electrical Reference blocks as needed.

I hope this helps!

You may read more about the blocks here:

Ideal Rotational Motion Sensor: https://www.mathworks.com/help/releases/R2023a/simscape/ref/idealrotationalmotionsensor.html

Ideal Angular Velocity Source: https://www.mathworks.com/help/releases/R2023a/simscape/ref/idealangularvelocitysource.html

Incremental Shaft Encoder: https://www.mathworks.com/help/releases/R2023a/sps/ref/incrementalshaftencoder.html

Voltage Sensor: https://www.mathworks.com/help/releases/R2023a/simscape/ref/voltagesensor.html

PS-Simulink Converter: https://www.mathworks.com/help/releases/R2023a/simscape/ref/pssimulinkconverter.html

Simulink-PS Converter: https://www.mathworks.com/help/releases/R2023a/simscape/ref/simulinkpsconverter.html