Prof.dr. F.C.T. van der Helm

I just really enjoy the work that I do

"If I had five times as long, I would be doing five times as many projects"

Frans van der Helm, professor Biomechatronica en Biorobotica

Frans van der Helm is Professor of Bio-mechanics and Bio-robotics. In 2012, he received the Simon Stevin Meester prize, the most important prize for technical-scientific research in the Netherlands. Like the STW Technology Foundation, Van der Helm is committed to realising knowledge transfer between the applied sciences and users. “Whatever we develop must ultimately reach society through industry.” 

Control lies at the heart of the work of Frans van der Helm and his department – controlling people and equipment. Ensuring that people can operate equipment in an optimum fashion requires knowledge of how control takes place in the human body itself. “We’ve come a long way in this regard”, he tells us. “Our department has a unique background; we combine control engineering with physiological systems.” The use of diagnostic tools is a special feature. “They exert a certain force on the joint of a patient, who must respond with a strength or position task. This allows us to take a precise measurement of how people control their arms or other body parts”, he explains. As in the case of many processes in the body, this happens with the aid of feedback systems. “Muscle spools and tendon organs send feedback to the central nervous system with regard to the position, speed and  strength of the muscle. These are the three most important feedback paths relating to movement. We are the only research group that is able to distinguish them.” This knowledge will ultimately benefit patients who are unable to control their movements effectively. Examples include people with disorders including Parkinson’s disease, cerebral palsy and multiple sclerosis. The STW research programme NeuroSIPE, which is led by Van der Helm, is investigating new methods of establishing diagnoses and monitoring diseases of the nervous system.

Van der Helm is also collaborating with Professor Gert Kwakkel of the VU Medical centre to develop a new method of making precise registrations of brain activity in place and time. “We are doing this in the same way”, explains Van der Helm. “We exert force and observe how people react to this. For this purpose we use high-density EEG with 256 electrodes. You could compare it to the localisation of earthquakes. We take measurements everywhere and calculate back to find the source of the signal.” Although this is not a new method, its degree of precision in time and place is new. Van der Helm would like to reduce this from the current half centimetre to two millimetres, with one measurement per millisecond. The EEG method is also expected to provide results quickly. “We are aiming to be able to perform the calculations within a few minutes. In clinical practice, it’s important to know what is wrong with a patient as quickly as possible.” In 2011, Van der Helm and Kwakkel received an Advanced Grant of € 3.5 million from the European Research Council (ERC) for this study. In addition to generating fundamental knowledge, the EEG study is focusing on a specific group: people who have had a stroke. “Nerve paths that run through the damaged part of the brain are destroyed and nerve cells degenerate. If we know which paths are still functioning and which connections with other parts of the brain remain, we can develop a better prognosis regarding the chances of recovery.” Once the damaged portion has recovered, the patient must re-learn movements through repetition. If this does not take place, the other parts of the brain – and in many cases, other muscle groups – will take over. This is an essential difference for the rehabilitation process. “Compensation by other parts of the brain requires looser commands, so that people can discover for themselves what works best for them”, explains Van der Helm. In his opinion, therapy focused on recovery is often pursued for too long. “If it doesn’t happen after a few weeks, it’s not going to happen. If we are able to support this with measurements, doctors will be able to take a decision to adjust the treatment sooner.”

Haptic feedback
The medical sector is not the only one to be interested in his work. Van der Helm and his team are also collaborating with industrial partners, including Nissan. The auto manufacturer is the first to apply ‘steer-by-wire’. This involves the car being controlled electronically rather than through a direct, mechanical connection between the steering wheel and the wheels of the car. Feedback is provided through the steering wheel, so that the driver feels what the car is doing. This is known as haptic feedback; haptic has to do with the sense of touch. “For example, it is possible to remove the countervailing power to the wheels when driving around a curve. The car then turns neatly into the corner, but you still have the feeling that you are doing it yourself. This makes for very comfortable driving, and it requires much less attention”, observes Van der Helm. The technology can also help drivers with parallel parking, staying in their lanes and avoiding obstacles. “Suppose there is a large stone in the road. The system helps you to steer around it, while you think that you have done it yourself. Because you do not realise that the car took over temporarily, you do not panic, and you retain control over the wheel.” Van der Helm has been working with Nissan for twelve years, to his great satisfaction. “Nissan sees the university as an explorer, as an entity in search of principles. That is exactly what it should be. Our work is relatively fundamental; they build a car around it.”

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