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A Grasping and Manipulation Scheme  175


              Table 9.1 Physical parameters for the simulations
              Three-fingered hand-arm system

              1st link length      l a1       1.300 m        l i1      0.300 m
              2nd link length      l a2       1.000 m        l i2      0.200 m
              3rd link length      l a3       0.175 m        l i3      0.140 m
              1st center of mass   l ga1      0.650 m        l gi1     0.150 m
              2nd center of mass   l ga2      0.500 m        l gi2     0.100 m
              3rd center of mass   l ga3      0.0875 m       l gi3     0.070 m
              1st mass             m a1       1.300 kg       m i1      0.250 kg
              2nd mass             m a2       1.000 kg       m i2      0.150 kg
              3rd mass             m a3       0.400 kg       m i3      0.100 kg
                                                                  2
                                       ð
              1st inertia, I a1    diag 7:453,7:453,0:260Þ 10  1  (kg m )
                                                                  2
                                       ð
              2nd inertia, I a2    diag 3:397,3:397,0:128Þ 10  1  (kg m )
                                                                  2
                                       ð
              3rd inertia, I a3    diag 0:291,0:291,0:500Þ 10  1  (kg m )
                                                                  2
                                       ð
              1st inertia, I i1    diag 7:725,7:725,0:450Þ 10  3  (kg m )
                                                                  2
                                       ð
              2nd inertia, I i2    diag 2:060,2:060,0:120Þ 10  3  (kg m )
                                                                  2
                                   diag 0:538,0:538,0:031Þ 10  3  (kg m )
                                       ð
              3rd inertia, I i3
                                                           0.070 m
              Fingertip radius, r i
                                                               5
                                                      1.000  10 N/m 2
              Stiffness coefficient, k i
                                                            2   2       2
                                                   1.000  r  Δr π Ns/m
              Damping function, ξ i
                                                           i   i
              Object
              Mass (m)                        0.037 kg
                                              0.092 m
              Y 1
              Y 2                             0.048 m
                                              0.048 m
              Y 3
                                              1.309 rad
              θ t1
                                              1.309 rad
              θ t2
                                              0.524 rad
              θ t3
                                                                             2
                                              diag 1:273,0:193,1:148Þ 10  3  (kg m )
              Inertia, I                         ð
                           N
                                  T
                          X
                   ðtÞ¼ K o  J ðtÞ f r x ðt  t delay Þ r xd + r y ðt  t delay Þ r yd
               u o real       Ωi
                          i¼1                                            (9.20)

                       + r z ðt  t delay Þ r zd g,
              where the orientation of the measured-object frame is expressed in the form

              of a rotational matrix, R tðÞ ¼ r x tðÞ,r y tðÞ,r z tðÞ 2 SOð3Þ. The sampling rate
              was taken to be h ¼ 20 Hz, and the time delay due to the computational cost
              of image processing and the latency of data communication was taken to be
              t image ¼ 50 ms.
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