c0849058-1179-43e1-848e-f7f91effdbb820210527045702786wseas:wseasmdt@crossref.orgMDT DepositWSEAS TRANSACTIONS ON BIOLOGY AND BIOMEDICINE2224-29021109-951810.37394/23208http://wseas.org/wseas/cms.action?id=4011316202131620211810.37394/23208.2021.18https://wseas.org/wseas/cms.action?id=23303AlexandreRabasedaMechanical Engineering Department at the University of Ottawa, 141 Louis-pasteur Private #159, Ottawa, on K1n 6n5, CanadaEmelieSeguinMechanical Engineering Department at the University of Ottawa, 141 Louis-pasteur Private #159, Ottawa, on K1n 6n5, CanadaMarcDoumitMechanical Engineering Department at the University of Ottawa, 141 Louis-pasteur Private #159, Ottawa, on K1n 6n5, CanadaHuman mobility exoskeletons have been in development for several years and are becoming increasingly efficient. Unfortunately, user comfort was not always a priority design criterion throughout their development. To further improve this technology, exoskeletons should operate and deliver assistance without causing discomfort to the user. For this, improvements are necessary from an ergonomic point of view. The device’s control method is important when endeavoring to enhance user comfort. Exoskeleton or rehabilitation device controllers use methods of control called interaction controls (admittance and impedance controls). This paper proposes an extended version of an admittance controller to enhance user comfort. The control method used consists of adding an inner loop that is controlled by a proportional-integral-derivative (PID) controller. This allows the interaction force to be kept as close as possible to the desired force trajectory. 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