Active Electrical Load Design for a Cluster POWER Rehabilitation System Chung-Hsien Kuo Department of Electrical Engineering National Taiwan University of Science and Technology Email: chkuo@mail.ntust.edu.tw http://mrl.wikidot.com/ 2017/11/12-15 Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 1
Outline Motivation and Objectives Methods Active electrical load module design Cluster POWER machine design with active electrical load modules Experiments and Results Conclusion and Future Works Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 2
Motivation and Objectives Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 3
Motivation Frailty syndrome is usually used to represent the elderly with degenerate function. Produce Outcome to Worthwhile for the Elder Reactivation (POWER) rehabilitation is a reactivation based rehabilitation modality that was proposed by Japanese Prof. Takahito Takeuchi. POWER has been clinically proven as an effective rehabilitation for frailty syndrome subjects. Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 4
Motivation Features of POWER rehabilitation POWER rehabilitation is done by using "low load" and repetitive motion to re-activate the non-active muscles. Current clinical solution (drawbacks) Conventional POWER machines used counterweights setting to change the load applied to subjects for rehabilitation. Manual setting of counterweights are not convenient, and the POWER machine with counterweights needs a large footprint. Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 5
Objectives - I This paper presents an active electrical load design to replace the use of heavy counterweights. Automated counterweights setting could be desirable from the control setting of an active electrical load module. The active electrical load module is formed based on conventional serial elastic actuator (SEA) designs. Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 6
Objectives - II Six rehabilitation modules for conventional solution were grouped as a cluster rehabilitation machine Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 7
Methods Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 8
Active Electrical Load Design An active electrical load module is wired formed with two sets of DC motors and springs. The springs are used to produce the compliance as well as to measure the forces applied on the corresponding spring. The produced active electrical load modules were linked to the cluster POWER (Produce Outcome to Worthwhile for the Elder Reactivation) machine for rehabilitation load generation. Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 9
Active Electrical Load Design Mechanical design for cluster machine Linear activation Rotational activation Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 10
Linear Activation Two-activation pairs for dual-way manipulations Active side: keeping desired resistance/ with PID force control (spring length variation) Passive side: keeping nearly 0 resistance, without differencing the function of activation side Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 11
Rotational Activation Similar design with the linear activation module Rotary mechanism was utilized for the manipulation of specific POWER rehabilitation T r L J K 1 (x) K 2 (x) F 1,q 1 F 2,q 2 M 1 M 2 Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 12
Hip Adduction/ Abduction Mechanical design with linear activation module Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 13
Integration of All Modules Considering force sensors Force sensor Seated row machine Chest press machine Leg press machine Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 14
Experiments and Results Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 15
SEA Resistance Tests Validated with a commercial force meter 5 kgf 7 kgf 10 kgf Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 16
Physical Operation Seated row machine Chest press machine Leg press machine Lateral trunk bending/ flexion Hip adduction/ abduction machine Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 17
Seated Row Machine 5 kgf 7 kgf 10 kgf Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 18
Lateral Trunk Flexion Machine 5 kgf 7 kgf 10 kgf Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 19
Lateral Trunk Bending Machine 5 kgf 7 kgf 10 kgf Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 20
Conclusion and Future Works Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 21
Conclusion A cluster machine with six rehabilitation functions were produced in this project in a prototype manner Electrical SEA may produce similar operation feeling when compared to conventional mechanical weight-added solution Sensors with load cells were considered to measure the force between user s upper limb and machine handle Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 22
Future Works Due to the mechanical design complexity and limited assembly space of combining six modules, only five module can be operated simultaneously. The leg extension machine can only work individually because of mechanical component intersections. Clinical validation of the muscle activation performance of SEA electrical load will be done in terms of comparing with commercial mechanical load machines. In the future, the space of the cluster machine must be rearranged. However, it is very challenge! Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 23
Thank you very much!!! Q&A in acknowledgement of MOST 105-2221-E-011-024 -MY2 Medical Robotics Laboratory, Department of Electrical Engineering, National Taiwan University of Science and Technology 24