A prototype of a portable data logger that can be attached to a wheelchair’s control mechanism may lead to tailored training and safer wheelchair use for people with dyskinetic cerebral palsy, according to a recent study.
The results, “Development of a Data Logger for Capturing Human-Machine Interaction in Wheelchair Head-Foot Steering Sensor System in Dyskinetic Cerebral Palsy,” were published in the journal MDPI.
Dyskinetic cerebral palsy (DCP) results from damage to the basal ganglia of the brain. Like an airport control tower, the basal ganglia coordinates the flow of information between the brain’s movement center and the spinal cord, and regulates control of voluntary movements. Due to this damage, the main feature of DCP is dyskinesia, or involuntary muscle movements. The exact nature of each person’s dyskinesia depends on the precise location of the damage to their basal ganglia.
Because of the trouble that people with DCP experience in controlling their movements, their wheelchairs often include computerized controls to operate smoothly, which require training to use. The study’s authors point out that because of the differences in each DCP patient’s individual dyskinesia, training should be tailored to each user.
Researchers at Leuven University in Belgium developed a small, battery-powered device that interacts with a wheelchair’s control mechanism. In conjunction with five small Inertial Measurement Units (IMUs) placed on the user’s body, they could directly analyze the interaction between the user and their chair.
Understanding a user’s learning process, particularly in the early stages of their training, could lead to better and safer driving techniques.
Housing their data logger within the wheelchair control unit made it less intrusive than other devices. Some of these place pressure sensors on the wheelchair seat, which users often find uncomfortable. Others require modifications to the wheelchair, or use of a mounted netbook.
To test their device, the team selected 10 people diagnosed with DCP and asked them to perform various wheelchair driving tasks. By comparing sensor data from these people to a healthy control, they successfully measured a variety of differences in wheelchair control, such as coordination during turning and braking.
Because the prototype data logger can acquire all signals related to the wheelchair driving control, it can also be used as a control device for wheelchair driving training with DCP patients. Their device, the researchers point out, is tailor-made for this population.
This study was largely supported by a private family, who donated a personal electric-powered wheelchair. Because this wheelchair came equipped with an Adremo head-foot steering system — one of the two head-foot steering systems used for this specific population — this was the only steering system tested with the new data logger. The team note, however, that the device is reconfigurable and may be adapted to other systems.
“The system … can be easily reprogrammed and provides real-time information of wheelchair head-foot driving. Due to the inability of DCP patients to control the fine movement of the limbs and the presence of involuntary movements, this system can be used for clinical research to gain insights into the mechanism of DCP during electric-powered wheelchair use, adapt the driving training of the user and evaluate driving performance,” the researchers concluded.
The development of better powered wheelchair technology is important to the cerebral palsy community for the independence and improved quality of life they offer their users.