Feature/smooth diff

[nyxrobotics]

Change Summary

Fixed a bug in the calculation of the differentiation of PID control. See the issue for details. This PR only fixes vesc_wheel_controller.cpp. I need another PR to fix vesc_servo_controller.cpp. Refactored PID controllers for both position control and velocity control.

• Fix #65
• Fix #67

Details

• I have created vesc_step_difference.cpp.
  • Classified functions for differentiating counter values.
• Refactored PID controller.
  • There was a bug in the I-control anti-windup.
  • Unnecessary variables were removed.
• Fixed parameters in launch file.

Impacts

• Robots that have been using PID control will need to readjust the gain.

References

Additional Information

• vesc_step_difference.cpp needs documentation.

[jsupratman13]

@Tacha-S

If you have no problem with it, I will merge it.

[Tacha-S]

OK. It's resolved what I was wondering. If I find any probrem, I will open a new issue.