Abdul_Sajan.pdf (4.2 MB)
Robust and fault tolerant control of modular and reconfigurable robots
thesis
posted on 2021-05-24, 10:07 authored by Sajan AbdulModular and reconfigurable robot has been one of the main areas of robotics
research in recent years due to its wide range of applications, especially in aerospace
sector. Dynamic control of manipulators can be performed using joint torque sensing
with little information of the link dynamics. From the modular robot perspective, this
advantage offered by the torque sensor can be taken to enhance the modularity of the
control system. Known modular robots though boast novel and diverse mechanical
design on joint modules in one way or another, they still require the whole robot
dynamic model for motion control, and modularity offered in the mechanical side does
not offer any advantage in the control design.
In this work, a modular distributed control technique is formulated for modular
and reconfigurable robots that can instantly adapt to robot reconfigurations. Under this
control methodology, a modular and reconfigurable robot is stabilized joint by joint, and
modules can be added or removed without the need of re-tuning the controller. Model
uncertainties associated with load and links are compensated by the use of joint torque
sensors. Other model uncertainties at each joint module are compensated by a
decomposition based robust controller for each module. The proposed distributed control technique offers a ‘modular’ approach, featuring a unique joint-by-joint control synthesis
of the joint modules.
Fault tolerance and fault detection are formulated as a decentralized control problem
for modular and reconfigurable robots in this thesis work. The modularity of the system
is exploited to derive a strategy dependent only on a single joint module, while
eliminating the need for the motion states of other joint modules. While the traditional
fault tolerant and detection schemes are suitable for robots with the whole dynamic
model, this proposed technique is ideal for modular and reconfigurable robots because of
its modular nature. The proposed methods have been investigated with simulations and
experimentally tested using a 3-DOF modular and reconfigurable robot.
History
Language
engDegree
- Doctor of Philosophy
Program
- Aerospace Engineering
Granting Institution
Ryerson UniversityLAC Thesis Type
- Dissertation