Project Freewheels: a human adventure looking at disability from another angle
© Inria / Photo C. Morel
On 8 October, Jérôme Parent will be competing in an exceptional cycle race.
Paraplegic for the last 21 years, he is regaining the use of his legs thanks to electrostimulation.
A close-knit team of Inria robotics researchers - but also a doctor and a physiotherapist - will be by his side.
He will take part in the Cybathlon in Zurich, a sporting competition between disabled sportsmen and women helped by new assistance technologies.
One of the six disciplines is electrical stimulation pedalling.
The few months of training he has undergone have already produced results: "I am rather proud of the fact that I am wearing shorts this summer," says Jérôme Parent. Completely paraplegic for the last 21 years, his thighs had rapidly lost their volume. However, the electrostimulation sessions he has put himself through with great discipline since November 2015 have enabled his muscles to regain some shape and part of their functions. "It is already a great victory", enthuses physiotherapist Anne Daubigney, who follows him in all the training sessions. The aim of this programme: during the Cybathlon*, cover 750 metres in under 8 mn on a three-wheeled bicycle, thanks to electrostimulations that will activate his leg muscles. Twelve other pilots have signed up for this event, including a Brazilian pilot prepared by a Camin partner team (see text box).
An experienced sportsman
Jérôme Parent was chosen for this adventure by Dr. Charles Fattal, medical head of the DIVIO functional re-education centre in Dijon. Firstly, from a medical point of view, his injury is such that voluntary nerve commands no longer function. On the other hand, the muscles can still be activated. A battery of tests were carried out in order to determine if his muscles could respond properly to the electrical stimulations after over 20 years of inactivity. The mineral density of his bones also needed to be sufficient in order to cope with the exercises, and tests were carried out to monitor his heart and blood pressure.
Motivation was also a determining criterion: the training programme takes place over the course of almost a year, at a rate of three sessions per week, so the pilot needed to have endurance. A sportsman, Jérôme Parent has always practised physical activities since his disability: diving, swimming...and cycling. He took part in a round of the world handbike championships in 2007, then in the European challenge (EHC) in 2007, 2008 and 2009. "Today, practising sport whilst being in good health is a matter of will - there is a wealth of tools and technical resources in order to do so." A passion for sport that therefore goes hand-in-hand with a keen interest in new technologies linked to disability: "I met Dr. Fattal because I had tried out an exoskeleton in Ireland. As soon as something new becomes available to me, I try it, explains Jérôme Parent."
Over several months, he has been training himself several times a week at home to receive electrical stimulations, lying down. Little by little, the muscles regain their mobility, the knees bend and straighten. Since May, he has been visiting the Dijon re-education centre three times a week for sessions in conditions very similar to those of the Cybathlon. In concrete terms, electrodes are placed on his legs, which are themselves fixed to the pedals. An electrical stimulator releases impulses that stimulate the muscles and cause them to contract. The pedalling system has been installed on a training bike loaned to the team by the company Berkel. "At first the challenge was to get him to pedal in a stationary position, before making him ride on a track," Anne Daubigney explains. He gets onto the cycle and fixes the pedals to his legs, as well as the strap to maintain himself in a sitting position, by himself. He places the electrodes and begins the electrostimulation. The exercises vary in both intensity and duration. "He is making progress with each session," she encourages him. She attentively monitors his skin to prevent sores and has drawn up an assessment grid taking into account both physical and psychological criteria. But for her, the most important scale is that regarding confidence and self-esteem. And, on that level, the gamble has already paid off.
A technological challenge
For the technical aspects, the Inria team Camin (Christine Azevedo, team head and Benoît Sijobert, PhD student) took over the project, called Freewheels. This joint team between the Nice Sophia-Méditerranée centre and the LIRMM (Laboratory of Computer Science, Robotics, and Microelectronics) in Montpellier, has specialised in neuroprostheses and electrical stimulation - technology similar to that of pacemakers. Their work helps people with sensory-motor impairments with, among other things, tools to aid posture, moving from seat to seat, walking assistance devices for patients suffering from hemiplegia, etc., as well as research on implanted stimulation technologies. They regularly work in collaboration with medical teams.
As part of Freewheels, they adapted a commercial three-wheeled bike and developed stimulation templates in order to obtain the best possible pedalling. Indeed, activating a pedal and gear mechanism requires - for an able-bodied person - the action of several muscles to obtain a precise movement. In the context of this experiment, only two superficial muscle groups are activated, and electrical stimulation has the effect of tiring them more quickly but also making the movement more random than with an able-bodied person. Christine Azevedo and Benoît Sijobert have also developed tools to assess the performance of the equipment and of the rider: "we were starting from scratch," they explain. Calculation of the angle of the pedal and gear mechanism, pedalling rate, travel speed and modulation of the stimulation: the technological solutions chosen are still likely to evolve between now and the competition, and beyond. For the implementation of this project, the Camin team received the support of Hikob, a company originating from Inria research, which lends them inertial units, and also from Matsport, who supplied force pedals. "Taking part in a competition obliges us to make choices that ensure there is a robust and optimised system for Jérôme, as much for pedalling as for the handling of the controls."
The ambition of these researchers:
Promote electrostimulation through a recreational activity and an international sporting competition
For the five members of the team, the number one goal was to take part in a beautiful human adventure. "The life of a disabled person is full of constraints, rues Dr. Fattal. Re-education, physiotherapy, medical monitoring, etc. They rarely have the opportunity to practise activities that they enjoy. With the Cybathlon, we are bringing together the pleasure of sport and an exciting technological project." The project has received financial support from INRIA and the NEUROGLIA endowment fund.
A Franco-Brazilian collaboration
A Brazilian pilot will also be on the Cybathlon starting line. For the last three years, the Camin team has been working together with a laboratory from the University of Brasilia. One of the Cacao team's research subjects - pedalling - is common to both laboratories. Their pilot will ride under the "Ema" banner. The aim: create an emulation and thereby envisage a greater number of technological solutions. On the other hand, the medullary injuries of the two riders are different: in Jérôme Parent's case, the injury is older and higher up, which means that his abdominal muscles no longer function. The two teams and their pilots had the opportunity to meet during a trip to Brazil, and regularly discuss the evolution of their work and the physical preparation of the pilots.