Rehabilitation robots are an increasingly widely used tool for training or assistance of patients. RRD is involved in the European Project COVR ( which focusses on the safety of robots working in shared spaces with humans. This includes collaborative robots in manufacturing, logistics and agriculture, but also rehabilitation and assistive robots such as exoskeletons. Those wearable robots for physical assistance or rehabilitation exert forces onto the user’s body to fulfil their purpose. Those forces are transmitted at a physical human-robot interface, often in the form of cuffs, splints or straps and can cause discomfort or injuries. In order to ensure safety of wearable robots, it is important to limit the forces exerted to the human body to avoid discomfort and injuries.

Problem statement:

Little is known regarding safe limit values for continuous and repetitive normal and shear forces exerted to the human soft tissue.


The primary objective of this research is to determine comfort thresholds for continuous and repetitive normal and shear stress exerted to the human thigh via a cuff with straps, using different force patterns comparable to those exerted during wearable robot use.


We are aiming to perform a study with healthy participants and potentially patients. A custom device for applying predefined forces to the participants’ thigh via a cuff is currently being developed. A continuous comfort rating collected during those sessions will help answer the research question.

Assignment description:

You will support the researchers in some or all phases of the study, including for example the ethical procedure, recruiting of subjects, execution of the experiments, data analysis and interpretation of the results.

The duration of the assignment is somewhat flexible, 4-6 months would be ideal. Starting date should be late 2021 or early 2022. Fluent Dutch and proficient English in oral and written form are required.


If you are interested or have any questions, please contact Jule Bessler ( and/or Gerdienke Prange (