Presenter : Jaya Bhanu RaoSupervisor : Dr. John Hedley Date : 20 July 2015

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WORLD CONGRESS ON INDUSTRIAL AUTOMATION 2015

Disabled or elderly people unable to manoeuvre powered wheelchair smoothly due to frail and lack of dexterity in handling joystick movement.

Leads to fatigue and discomfort to wheelchair users.

Smooth wheelchair movement and transition are needed to overcome this problem.

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To develop a robust algorithm to detect and avoid static and dynamic obstacles.

To develop a control system which can assist the wheelchair user in minimising the sharp shifting of wheelchair movement.

To validate wheelchair navigation via joystick using Matlab and Player/Stage simulation on Ubuntu 12.04LTS platform.

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Go To Target

Laser Obstacle Avoidance

Unobserved Obstacle Avoidance

Follow the Leader

Emergency Stop

Env

iron

men

t

Fuz

zy L

ogic

Σ

Laser

Input Device (User)

Laser

Laser

Laser

Converter

MCU

Motor Controller

Perception Reactive Module

Support AI Motor Schema

vect

or

weightage

vect

or

Out

put v

ecto

r

Spe

ed, t

urnr

ate

ν, Ω

Action

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Point distance based segmentation (PBDS)

K.Rebai et. al. 2009

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• Collision avoidance can be divided into static and dynamic obstacle. These obstacles can be avoided with collision avoidance behaviour which is based upon VO method and Collision Cone principle.

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Fiorini and Shiller, 1998; Chakravarthy and Ghose, 1998

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The inputs of the emergency stop behaviour include the sensor data and the maximum weight of the wheelchair speed. This behaviour becomes active if the minimum distance to the obstacle is below a minimum specific threshold or the maximum weight of the robot velocity is zero.

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Ceballos et al., 2010

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Based on the simulated results it have been proven that there was a significant improvement in the wheelchair movement with Fuzzy Inference System.

Further work will be carried out to introduce other behaviours and to further improve the performance of the system.

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