Admittance Control of Bravo 7

Dynamics & Controls

Overview

Underwater manipulation tasks require precise manipulator and vehicle control to safely complete tasks like environmental sampling and dock maintenance. As underwater vehicle-manipulator systems (UVMS) are subject to complex hydrodynamic motions, UVMS must account for any undesired dynamic changes or external forces that occur during a manipulation task. In this paper, we propose an admittance control law that uses measured end-effector forces to determine the compliant motion required to minimize interaction forces. With this approach, we demonstrate, both in simulation and hardware, results for compliant motion of a manipulator that minimizes interaction forces.

Methods

  • Simulation
  • Admittance Control

Tools

  • MATLAB
  • Python

Samples

Bravo Arm Simulation
Gif of Simulated Forces on Bravo Arm
Admittance Control On Real Hardware
Gif of Real Forces on Bravo Arm
Admittance Control Sim Plot
The real admittance controller response on the Bravo 7 when force is applied to the manipulator’s end effector
Admittance Control On Hardware Graph
The simulated admittance controller demonstrates compliance when a 25N force is applied to the manipulator’s end effector