Electronic Thesis and Dissertation Repository

Thesis Format



Master of Engineering Science


Electrical and Computer Engineering


Kermani, Mehrdad R.


In recent years, Magneto-Rheological (MR) fluids has been used in various fields such as robotics, automotive, aerospace, etc. The most common use of the MR fluids is within a clutch-like mechanism, namely an MR clutch. When mechanical input is coupled to the input part of the MR clutch, the MR clutch provides a means of delivering this mechanical input to its output, through the MR fluids. The combination of the mechanical input device and the MR clutch is called an MR actuator. The MR actuator features inherently compliance owing to the characteristic of the MR fluids while also offering higher torque-to-mass and torque-to-inertia ratios over common actuators. As such, MR actuators are suitable candidates for human-safe and collaborative robots.

The goal of this study is to design, develop and test customized electronic drivers that are compact and powerful to enable effective low-level control of the robot joints. The electronic drivers are responsible for sensor data processing, between-joint communication, supplying electric power, and executing control actions. The hardware design is optimized to handle transient current and voltage, and dissipate heat generated by components. Moreover, software development is based on μ C/OS-II real-time operating system to handle multiple time-critical tasks and to guarantee the stability and effectiveness of robot control system. A series of experiments are conducted to validate the designed hardware and software systems, and evaluate their performance.

Summary for Lay Audience

Magneto-Rheological (MR) fluids are smart materials that have increasingly been used in developing essential components of the robot, automotive, aerospace, etc. Its rheological properties change fast and reversible under the effect of an external magnetic field. In the field of robot development, MR fluids is commonly used to develop the MR actuator. It can deliver the mechanical input to its output through the MR fluids. The difference between the MR actuator and the commonly seen electric actuator is that the MR actuator features higher performance and inherently compliance. As such, MR actuators are suitable candidates for human-safe collaborative robots. Based on that, we are developing 5 degrees of freedom collaborative robot.

This dissertation focuses on design a compact and powerful electronic driver to enable effective low-level control on the joints of a human-robot-safe collaborative robot. The hardware design is optimized to handle extreme situations. The software design is based on a real-time operating system to guarantee the instantaneity and effectiveness of the robot control system. Then, the control system for controlling the entire robot is constructed by building the connection between electronic drivers. Experiments are conducted to evaluate the performance of the robot and software/hardware systems.