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Online PhD defense by Miguel Nobre Castro

Online PhD defense by Miguel Nobre Castro

Development of a Passive Orthosis for Upper Extremity Assistance — Towards a Subject-specific Device by means of Musculoskeletal Modelling


01.05.2020 kl. 13.00 - 16.00


Watch the defense on youtube 


Neuromuscular impairment caused by disorders or injuries reduces the quality of life of those that, in the absence of a healthy motor function, have trouble living independently. Patients may undergo continuous physical rehabilitation and this process sometimes involves the use of arm assistive technologies, which can exploit their residual motor function. These devices have shown effectiveness in enabling independent living but they tend to be cumbersome, hardly wearable and stigmatizing. Accomplishing a lightweight, compact, and inconspicuous design of a wearable device still remains a challenge. Thus, new design approaches that enhance treatment and do not compromise the assistive requirements must be investigated.

In this PhD study, a passive upper extremity orthosis is designed for patients with neuromuscular disorders using prior knowledge obtained from subject-specific musculoskeletal modelling and simulation. To that end, the assessment of the motor performance of the upper extremity is initially studied by means of estimating the reachable 3-D workspace as function of different hand-payload conditions and measurements of anthropometry and strength capabilities. Musculoskeletal models are built, scaled and validated for ten test-subjects using the reachable 3-D workspace. Such workflow is replicated on two adolescents with arthrogryposis to investigate their motor function. Patient-specific models are optimised and evaluated by comparing simulated reaching capabilities of the patients against their experimental counterparts.

Afterwards, a novel compact shoulder mechanism with three degrees-of-freedom is created for exoskeleton/orthotic applications. This non-stigmatizing spherical scissors mechanism fits close to the body, being able to fit underneath clothing, and perfectly matches the kinematics of the anatomical shoulder joint. The mechanism is, then, used on a passive feeding-assistive orthosis prototype that is designed for partial balancing of the upper extremity using a closer to the body spring configuration, and allows the user to body-power the device with residual muscle function of their antagonistic musculature. The results show that the impaired patient is able to reach the frontal region of the reachable 3-D workspace and able to reach her mouth independently. When combined with musculoskeletal simulation, such design approach may be able, in the future, to enhance treatment by targeting the rehabilitation of specific muscles.


  • Associate Professor, Lotte Najanguaq Søvsø Andreasen Struijk  (chairman)
  • Department of Health Science and Technology Aalborg University, Denmark
  • Professor Jaap Haalar, Department of Biomechanical Engineering  Delft University of Technology, The Netherlands
  • Professor, dr.ir. H.F.J.M. Koopman (Bart), Department of Biomechanical Engineering University of Twente, The Netherlands


  • Associate professor Michael Skipper Andersen, Department of Materials and Production, Aalborg University


  • Professor Shaoping Bai, Department of Materials and Production, Aalborg University


The PhD defense will be hosted by Moderator Erik Lund. The lecture constitutes a 45 minutes presentation by Miguel Nobre Castro followed by a short break and a discussion session with questions from the opponents and the auditorium.




Department of Materials and Production

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