An old, fatigued washing machine has some loose fasteners which protrude inside the drum and latch...

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An old, fatigued washing machine has some loose fasteners which protrude inside the drum and latch onto the clothing during the spin cycle as shown in Fig. 1. An approximation of the out-of-balance system is presented in Fig. 1 with critical dimensions provided, the eccentric masses can be approximated as uniform, spherical geometries with an average density of 650 kg/m. Assume that the drum rotates counter-clockwise with a constant angular velocity of 1100 rpm under steady-state operating conditions and the influence of the acceleration of gravity can be neglected. a) Calculate the mass and equivalent radius of the centroid with respect to the axis of rotation for the eccentric masses shown in Fig. 1. b) Draw the lumped parameter model of the system, identify the equivalent point masses and locations of the eccentrics, coordinate system, angular velocity vector and bearing supports. c) Generate the table of key parameters with consideration for the out-of-balance masses and bearing reactions, take the plane containing eccentric A as the datum for the moments. d) Calculate the total out-of-balance force and the out-of-balance moment, as vectors, and determine the latter with respect to the plane containing Bearing support A. HINT: Ignore the influence of the bearings for this stage of the problem. e) Determine magnitude and angular orientations of the bearing reaction forces in planes A and B necessary to cancel/eliminate the out-of-balance forces and moments. H-850 mm 250 mm Bearing support 'A' Darum-600 mm D = 200 mm 150 mm/ 450 60 x 90 Bearing support 'B' 350 mm An old, fatigued washing machine has some loose fasteners which protrude inside the drum and latch onto the clothing during the spin cycle as shown in Fig. 1. An approximation of the out-of-balance system is presented in Fig. 1 with critical dimensions provided, the eccentric masses can be approximated as uniform, spherical geometries with an average density of 650 kg/m. Assume that the drum rotates counter-clockwise with a constant angular velocity of 1100 rpm under steady-state operating conditions and the influence of the acceleration of gravity can be neglected. a) Calculate the mass and equivalent radius of the centroid with respect to the axis of rotation for the eccentric masses shown in Fig. 1. b) Draw the lumped parameter model of the system, identify the equivalent point masses and locations of the eccentrics, coordinate system, angular velocity vector and bearing supports. c) Generate the table of key parameters with consideration for the out-of-balance masses and bearing reactions, take the plane containing eccentric A as the datum for the moments. d) Calculate the total out-of-balance force and the out-of-balance moment, as vectors, and determine the latter with respect to the plane containing Bearing support A. HINT: Ignore the influence of the bearings for this stage of the problem. e) Determine magnitude and angular orientations of the bearing reaction forces in planes A and B necessary to cancel/eliminate the out-of-balance forces and moments. H-850 mm 250 mm Bearing support 'A' Darum-600 mm D = 200 mm 150 mm/ 450 60 x 90 Bearing support 'B' 350 mm