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TECHNOLOGIES FOR MOTOR BEHAVIOUR ANALYSIS AND VIRTUAL MODELLING September 26, 2016 EXERCISE 1 A force platform with longitudinal length a=500mm, transversal length b=300mm and thickness d=10mm undergoes a calibration procedure consisting in placing a stick on the upper surface and rotating it following a circular trajectory with radius r=200mm while the tip of the stick (ideally a point) is maintained fixed on the platform surface, as shown in Fig. 1. Discuss what happens to the center of pressure cp on the platform upper surface during the movement (consider the force applied by the stick directed along its axis of symmetry). Supposing that the system erroneously computes the location of the point cp at a height of d*=8mm from the sensors plane (lower surface), calculate the percentage of error committed in respect to the real position of cp. Figure 1 EXERCISE 2 Considering the following charge amplifier, discuss how the frequency response changes in the case of Ri = 0 Ω and Rp = ∞. EXERCISE 3 Three different cameras look at the same calibration grid returning different images. 1) Considering the image provided by each camera and the description of the relative system, link the system to the correct calibration matrix, briefly explaining the reason. 2) Supposing the cameras already corrected for the distortions, tell the minimu m number of known points ( i.e., with known coordinates) required to estimate the three overall calibration matrixes. System 1: origin of the sensor coordinate system: bottom left sensor dimension in pixels: 2000x2000 pixel size: 10x10μm System 2: origin of the sensor coordinate system: bottom left sensor dimension in pixels: 1000x1000 pixel size: 10x10μm System 3: origin of the sensor coordinate system: bottom left sensor dimension in pixels:…