Differences

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--- control_system [2023/05/03 15:58] – ursgraf
+++ control_system [2023/05/11 17:13] (current) – [Motor Model] ursgraf
@@ Line 37: / Line 37: @@
 ==== Controller ====
-The "Motor Model" gets the actual speed and the calculated torque as input, and outputs the desired voltage for each motor.\\
+The position of the TCP is controlled by taking in the setpoint (see above) and adding planned velocities and accelerations. The resulting total acceleration is then fed into the block 'Inertia' which - through Newton's law - calculates the resulting force. This force is still in cartesian coordinates and has to be translated into torques applied to each of the three motors.
-The "voltageSetPoint" serves for the initializing of the encoder. This block is no longer used after reaching Safety Level "systemReady".
+==== Motor Model====
+As our board cannot only control voltages fed to each motor, we must use a motor model to calculate these voltages. The block 'Motor Model' gets the actual speed and the calculated torque as input, and outputs the desired voltage for each motor. We must also take the gear into account. The speed is reduced by the gear ratio while the torque must be multiplied with the same ratio. The following equation holds
+<code>
+U = kM * w + I * RA + dI/dt * L
+</code>
+with I = M / kM and dI/dt * L beeing very small with our motors and accounting for the gear i we get
+<code>
+U = kM * w * i + M * RA / (kM * i)
+</code>
 ==== Outputs ====
 The drive signals to the motor are of type ''PeripheralOutput''. They are described in the HAL as well.
@@ Line 44: / Line 53: @@
 eeros::control::PeripheralInput<double> mot1("motor1");
 </code>
+The block 'voltageSetPoint serves for the initializing of the encoder when homing. It drives the motors with slow speed into a mechanical stop. This block is no longer used after reaching Safety Level ''systemReady''.