Control Systems

BumbleBee 2.0 has six degrees of freedom: surge, sway, heave, roll, pitch and yaw. Six PID (Proportional Integral Derivative) control loops are tuned to control the vehicle’s underwater dynamics. The PID controllers are designed with the following

considerations:

  • Low pass filter for the derivative component to reduce the exponential effects on sensor noise
  • Variable period time sampling for more accurate computation of the integral and differential components
  • Weighted set points to reduce transient effects in set point changes
  • Integrator windup protection for when actuators are unable to fulfill the PID Controller requirements

The PID control loops have been improved for dynamic allocation of actuator limits, allowing greater output in specific degree of freedoms. Velocity controllers for the surge and sway domains have been implemented for more precise maneuvering of the vehicle during mission tasks. A User Interface was designed by the software team to facilitate PID Tuning. (Click here for more info)