IJAT Vol.11 No.3 pp. 442-449
doi: 10.20965/ijat.2017.p0442


Elbow Musculoskeletal Model for Industrial Exoskeleton with Modulated Impedance Based on Operator’s Arm Stiffness

Daniele Borzelli, Stefano Pastorelli, and Laura Gastaldi

Politecnico di Torino
Corso Duca degli Abruzzi 24, 10129 Torino, Italy

Corresponding author

October 1, 2016
April 10, 2017
Online released:
April 28, 2017
May 5, 2017
arm stiffness, hill muscle model, elbow model, exoskeleton

With the ageing of the workforce in the manufacturing industry, the possibility of introducing support aids such as exoskeletons to reduce the fatigue and effort of the operator has to be evaluated. An upper-limb exoskeleton with controlled impedance is expected to reduce the discomfort in the operations which require precision. Hence, arm joint stiffening is required. Real-time calculation of the exoskeleton impedance should be based on the operator’s limb impedance, evaluated through electromyographic signals. A model of the operator’s arm is necessary to identify the best control law for the exoskeleton. In this paper, preliminary considerations and a model of the elbow on which two muscles act as agonist-antagonist are presented. Numerical results are discussed, and an estimation of the performance is also proposed.

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Last updated on Sep. 21, 2017