University of Michigan researchers have designed a low-cost, portable arm rehabilitation robot, which they suggest can be used at home and facilitate motor recovery in patients with cerebral palsy, stroke, or spinal cord injury.

The development of the rehab robot, named PaRRo, is described in a study published in the journal IEEE Transactions on Biomedical Engineering.

PaRRo was designed to provide task-specific training, according to the researchers, in a news story from Cerebral Palsy News Today.

It features an effector at the end of a robotic arm, which is engineered to be maneuvered by the patient. The effector is connected to a system of brakes that offer resistance to the arm’s movement, training muscle strength and improving arm resistance.

The amount of resistance can be controlled by each patient, meaning that the arm exercise intensities can be adapted to each patient’s motor skills.

However, the news story continues, the rehab robot is passive, which means it does not have any computer control, nor does it actively operate by taking over from the user.

In their research, the team performed simulations to calculate the robot’s resistive force and workspace. They then constructed a prototype based on these results, which was tested in a healthy male volunteer with no neurological or orthopedic impairments.

Nine surface electrodes were placed in different muscles and recorded the muscle activity via electromyography.

Both the force generated by the robot and the force produced by the user matched those predicted by the simulations when the device was moved across different directions.

Electromyography results also revealed the robot was capable of generating resistive forces adjustable to the subject’s motor abilities, the news story explains.

“These results indicate that PaRRo is a feasible low-cost approach to provide functional resistance training to the muscles of the upper-extremity,” according to the researchers, in the study.

“The proposed robotic device could provide a technological breakthrough that will make rehabilitation robots accessible for small outpatient rehabilitation centers and in-home therapy,” they add.

[Source: Cerebral Palsy News Today]