Loading...

Impedance Control of Balance Robot

Rafiee Javazm, Mohammad | 2018

656 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 51282 (08)
  4. University: Sharif University of Technology
  5. Department: Mechanical Engineering
  6. Advisor(s): Behzadipour, Saeed
  7. Abstract:
  8. In recent years, rehabilitation has become of particular importance due to direct connection with the quality of life of human beings. Balance training and assessment devices have been designed to provide means for rehabilitation of patients with balance problems. Sharif balance robot is an example which has been developed at Sharif University of Technology. The subject stays on a plate with active rotation in both Medial-Lateral and Anterior-Posterior directions. The active rotation of this plate is provided by two electrical motors embedded inside the machine. Position commands for this plate are sent to the electrical motor by the control hardware which consists of a PC104 running MATLAB/XPC-Target. It also has four force sensors at the corners, which allows the controller to locate the center of pressure at any moment, which is used as a feedback in the control loop. In the present project, we plan to control the moving plate so that the person feels that he is on a plate with a certain stiffness and attenuation. This facilitates several rehabilitation scenarios to be implemented on this robot. Also, this feature can be used to simulate another rehab device, Biodex SD, which is quite popular in balance rehab. The first step for the design of the controller is modeling and obtaining the dynamical equations of each system. The main parts of balance robot are: human and its central nervous system, the mechanical transition of motion from the motor to the moving plate and the electrical motors. Each them was individually modeled. Then the interactive force between the human and the moving plate was measured with the force sensor and according to it, the command was given to the motors. After implementing the controller on the balance robot, it was concluded that the error between the desired and actual impedance increases with increasing frequency. But in the human frequency range below 15 Hz, the desired impedance, including stiffness and attenuation, was followed by a margin of error of 3% and 9%, respectively
  9. Keywords:
  10. Rehabilitation ; Servomotors ; Impedance Control ; Balance Rehabilitation ; Model Reference Control ; Balance Robot ; Pressure Center

 Digital Object List

 Bookmark

No TOC