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TECHNOLOGIES FOR MOTOR BEHAVIOUR ANALYSIS AND VIRTUAL MODELLING June 30, 2021 Written Test. Max points 110 (equivalent to 33/30). Min points 60 (equivalent to 18/30). Duration 60 minutes QUESTION 1 [5/110] Who was thinking that muscles are activated by electricity? • The balloonists • Ancient Greeks • Luigi Galvani • Benjamin Franklin • Thomas Edison QUESTION 2 [10/110] This is the schematic representation of Hill model. Please describe briefly the nature of each lumped component. Correct answers: The model is constituted by a contractile element (CE - muscular Fibers), two non- linear spring elements, one in series (SE - Tendon characteristics) and another in parallel (PE – Collagen tissue), and a non-linear distributed viscous damper (DE). QUESTION 3 [10/110] Briefly explain the reason of the stochasticity of the EMG signal Correct answers: Recruitment of fibers is not predictable, depending on interneuron activity. In the MUAPT repetition of MUAP happens at unpredictable time intervals, so the overall interferential signal is never the same, nor can be predicted. QUESTION 4 [5/110] Which of the following is an approximation of a polarizable electrode for measuring EMG? • Hydrogen electrode • Ag-AGCl electrode • Platinum electrode (inert metal) • Polarizable electrodes do not exist • Metal Electrode exchanging actual charges with the body QUESTION 5 [15/110] What does this schematic represent? What is the overall gain to differential and common mode at the leads + and -? What are the two main characteristics of this configuration with respect to the single amplifier in differential configuration? Please define the values of resistors for obtaining a gain of 402 in differential mode and 2 in common mode. Correct answers: It is an instrumentation amplifier. The…