Scenarios and Clinical Trials

Scenarios and Clinical TrialsAnnemarie Kokosy, Gareth Howells, Mohamed Sakel &

Matthew Pepper ISEN/University of Kent/EKHUFT

January 27th, 2012Ecole Centrale of Lille

1Part-financed by the European Regional Development Fund

Part-financed by the European

Regional Development Fund

Plan of presentationI. First Scenario

1. Description2. Prototype3. Clinical evaluation

II. Second Scenario4. Description5. Prototype6. Clinical evaluation

III. Third scenario

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First Scenario – Collision Avoidance• Description

– The user drives the powered wheelchair via a joystick– The intelligent device must

• Detect obstacles • Slow down the PW proportionally to the distance between the

obstacle and the wheelchair• Stop the PW if the distance between the PW and the obstacles is

less than the security distance, overriding any action by the user • Provide the user with visual feedback on the distance (measured

by the sensors) between the wheelchair and the obstacles in its way

• Have a switch to allow the user to enable or disable the device

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First ScenarioHardware Implementation at ISEN

• ISEN Prototype– 2 electronic boards: 1 for the joystick and 1 (Arduino) for the

data processing and navigation strategy– 9 US sensors– 2 IR sensors– visual feedback

DupontMedical with DynamicControls

4Invacare Storm 3 with DynamicControls



First Scenario Hardware Implementation at UoK

• ISEN Prototype– The technical report to replicate the intelligent module

(deliverable A3D1) is available and was sent to University of Kent at the end of November 2011

DupontMedical with DynamicControls

5Invacare Storm 3 with DynamicControls



First scenarioHardware Implementation at UoK

Prototype at University of Kent INVACARE Harrier Plus wheelchair Dynamics Control System

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• Processing, Beagle board or equivalent.• Sensor boards, Arduino or equivalent.• Sonar 5m (LV-MaxSonar-EZ4 MB1040). • I/R 5m (SHARP - GP2Y0A710K0F).• I/R 1.2m (SHARP-P2Y0A02YK0F).• Optical camera and Fisheye lens.• Magnetic compass (CMPS10).• Floor colour sensor (Inex).• Dynamic object sensor (GE/ ZTP-135S).• Drive shaft angular rate (existing motor).• Angular body rate (MLX90609-E2).• Acceleration/velocity (ADXL320).• Position (optical mouse sensor).



First scenario• Clinical Trial: Hospital of Garches

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First partSecond part



First scenario: Clinical Trial - HG• Pilot study of 27 people divided into 3 groups

– Group1: 9 healthy volunteers who have never driven an electric wheelchair

– Group2: 9 experienced electric wheelchair users– Group3: 9 users who didn’t pass the electric wheelchair

driver’s licence

• Goal: reduce the number and severity of collisions • Methodology: create a circuit that simulates a real life

indoor environment (walls, doors, obstacles)

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First scenario: Clinical Trial - HG• Evaluation Criteria: the number of collisions during the

test, and the time the user needed to finish it.• Total duration of the test: 3 hours• Duration of the study: 5 months• Ethics Approvals: The clinical protocol has been approved

by AFSSAPS (French agency for health and sanitary security) and the CPP (Commission for the protection of people) at the end of December 2011

» The clinical protocol and the observation booklet were sent to EKHUFT in November 2011

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First Scenario: Clinical Trial - HG• 3 users (from groups 1 & 3), have already taken

the test• Some technical problems were identified

– To go through doors (90cm)– To navigate along the corridor with obstacles (distance wall

– obstacle = 1m)– For reverse navigationSolution (in progress)

• To better locate the sensors to reduce dead zones• To change the navigation strategy

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First Scenario: Clinical Trial - EKHUFT

• Pilot Study to Confirm Findings from HG– 9 healthy volunteers – 9 Patients selected by Dr Sakel

• Provision of ISEN interface by UoK - ?• Testing of ISEN Interface at UoK - ?• Ethics Approval: The clinical protocol has to be developed

and application made to the National Research Ethics System via the Integrated Research Application System (IRAS) – October 2012

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First Scenario: Clinical Evaluation - EKHUFT

• Repeated for each patient over Hospital stay• Evaluation Criteria:

– Number of collisions during the completion of the clinical test path– The time to complete the path.

• Patient Evaluation/Experience – Questionnaire to be developed

• Subject Participation duration: 1hour?• Duration of the study: 5 months• Possibly at same time as Scenario 2?

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Second scenario (HG)• Description

– The user drives the powered wheelchair using a joystick– The intelligent device must

• Detect obstacles• Detect Steps/Stairs • Avoid obstacles, overriding any user action if necessary• Go autonomously through doorways• Provide feedback to the user (must be visual or audible)• Have a switch to allow the user to enable or disable the device• Have a switch to allow the user to enable the “pass through

doorways” mode

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Second scenario• Prototype: new challenges

• Obstacle avoidance idea: use the potential field method (the joystick direction=attractor; obstacles = repulsor)

• Second prototype vs first one– Use of US and IR sensors for obstacle detection– Use the Arduino board for data processing– New data: camera and/or laser for position and velocity estimations– Use of a PC or mother board (If PC not allowed for the ethics approval)

for data processing and navigation algorithm– What kind of device for the user's feedback ?– A switch to change between the autonomous or semi-autonomous

navigation

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Second scenario• Prototype: who uses what kind of sensors and

for which goal?

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ISEN/EC Lille University of Kent

University of Essex

US and IR Obstacle detection

localisation perception

camera localisation localization

Kinect perception

Laser perception

Inertial sensors localization

GPS localization



Second scenario• Main results

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ISEN/EC Lille University of Kent University of Essex

Localization Use one cameraand one or two landmarks (OK on simulation)

Use US (indoor), GPS (outdoor), inertial navigation system on the real robots

Perception Use of US and IR sensorsStatic obstaclesDrawback: the system is too slow

? Kinect, laser, camera, to build the maps (SLAM)

Speed estimation Use one cameraand one or two landmarks (OK on simulation)Observers and estimators

Inertial navigation system

Path Planning Michel A*

Tracking and Control Sarah & Thierry PID Control, Fuzzy (Huosheng)



Second Scenario: Clinical trial• Hospital of Garches

– Define the clinical protocol with the SYSIASS team– Ask for the Ethics approval– Initial Evaluation of the prototype in a clinical environment

– January 2013?

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Third Scenario• Based on the first results of the survey on user

needs• Survey

– Start date: November 2011 – End date: April 2012– Questionnaire available in French and English on our web

site (www.sysiass.eu)– Realized by ISEN/GHICL in collaboration with 2

rehabilitation centers (Berck sur Mer and Villeneuve d’Ascq) and the Social Institute of Lille

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http://www.sysiass.eu/



• First results of survey: ConclusionScenario 1: collision avoidance

The intelligent device doesn’t correct the trajectory

Scenario2: assisted navigation in semi-autonomous way The user drives the powered wheelchair The intelligent device avoids obstacles with the user action on the loop The going through doorways is autonomous (the user chooses this

option)

The survey results allow us to define a third scenario: autonomous navigation

EKHUFT also proposes a scenario (see the next presentation)

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Third scenario



Project plan – Time line

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Feb/2012 Aug/2012 Feb/2013 Aug/2013 31Dec/2013End

1st scenarioTechnical work

4/12 6/12 10/12 12/12 4/13 6/13 10/13 12/13

Clinical trials

2nd scenario

3rd scenario

Technical work

Clinical trials

Technical work

Clinical trialsEthics Approval

Ethics Approval

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Scenarios and Clinical Trials