Parametric Scaling of a Lower Limb Model According to Body Height in OpenSim

Abstract

The standard preprocessing for simulations in OpenSim requires experimentally acquired motion data of an individual. This paper presents an approach for scaling musculoskeletal OpenSim models using an estimation of body measures according to the body height from the MMM Reference Model, instead of a recorded static pose of a subject. In this way, the data acquisition effort should be reduced using data from existing motion databases. For a first validation of the approach, 1) a pre-study is carried out to evaluate the estimations of the body segment lengths from the MMM Reference Model and 2) a gait study to compare the kinematics of a scaled model using experimental data with a scaled model using our scaling approach. The errors between real and estimated body dimensions are around 10 % resulting in up to 10° differences between the joint angles of the differently scaled models. In general, the scaling approach shows the potential of reducing effort in the simulation preprocess.

Keywords: User-Centered Design, Musculoskeletal Simulation, OpenSim, Exoskeleton

DOI: 10.54941/ahfe1002711