Dr. Ashish Dutta

Professor, Dept. of Mechanical Engineering

Email:adutta@iitk.ac.in

Office: Faculty Building Room 338
Phone:91-512-2597562 (Off.), 2598710 (Res)
Fax:91-512-2597408

Affiliated Center(s):

Centre for Mechatronics

Design of an optimal
finger exoskeleton based on human motion data

Outline:

Objective : understanding synergy between: hand kinematics - muscles - brain.

§ Human finger motion biomechanics.

§ Optimal design of a hand exoskeleton.

§ Hybrid control (EEG+EMG+Dynamics)

Finger biomechanics:

•How do humans perform simple object manipulation (rotation + translation) ?

Simple task of moving a coin and its motion analysis(NAIST Japan):

- 30 subjects performed this task.

Axes notation for each joint:

Manipulability calculation based on joint positions:

Ellipsoid calculations:

•Activity of each finger :

•Ellipsoid volume

•Direction of major axis of ellipsoid

•Ratio of axes

Rotations and 3D motion:

Design of finger exoskeleton:

•Three finger exoskeleton (index-middle-thumb).

•Grasping and simple manipulation ability.

•Control using EMG / EEG, Inverse kinematics.

•Use in stroke rehabilitation, assistive robot, physical therapy.

Thumb and middle finger:

Links made by rapid prototyping and actuated by ultrasonic motors:

Fabrication of the exoskeleton: Rapid prototyping:

Three finger exoskeleton for exact finger motion emulation:

- 10 DOF actuated by ultrasonic motors.

- Both translations and rotations are possible.

- Control : NN and Inverse Kinematics

New 4 DOF Two finger exoskeleton for Stroke Rehabilitation

Hybrid control:

Augment EMG with EEG for Control

Flow chart of the control strategy: EMG + EEG signal recording - Feature extraction and classification - control of joint motors.