  In cable driven parallel robots (CDPRs), a single cable malfunction usually
induces complete failure of the entire robot. However, the lost static
workspace (due to failure) can often be recovered through reconfiguration of
the cable attachment points on the frame. This capability is introduced by
adding kinematic redundancies to the robot in the form of moving linear sliders
that are manipulated in a real-time redundancy resolution controller. The
presented work combines this controller with an online failure detection
framework to develop a complete fault tolerant control scheme for automatic
task recovery. This solution provides robustness by combining pose estimation
of the end-effector with the failure detection through the application of an
Interactive Multiple Model (IMM) algorithm relying only on end-effector
information. The failure and pose estimation scheme is then tied into the
redundancy resolution approach to produce a seamless automatic task
(trajectory) recovery approach for cable failures.

Robotics