Search results for "Kinematic chain"
showing 2 items of 2 documents
Modular Control of Pointing beyond Arm's Length
2009
Hand reaching and bipedal equilibrium are two important functions of the human motor behavior. However, how the brain plans goal-oriented actions combining target reaching with equilibrium regulation is not yet clearly understood. An important question is whether postural control and reaching are integrated in one single module or controlled separately. Here, we show that postural control and reaching motor commands are processed by means of a modular and flexible organization. Principal component and correlation analyses between pairs of angles were used to extract global and local coupling during a whole-body pointing beyond arm's length. A low-dimensional organization of the redundant ki…
A robust forward-displacement analysis of spherical parallel robots
2009
The forward-displacement analysis of spherical parallel robots (SPRs) is revisited. A robust approach, based on the input–output (I/O) equation of spherical four-bar linkages, is proposed. In this approach, the closed-loop kinematic chain of a SPR is partitioned into two four-bar spherical chains, whose I/O equations are at the core of the analysis reported here. These equations lead to a trigonometric equation in the joint angles, which is solved semigraphically to obtain the joint variables for the determination of the moving plate orientation. Examples are included to demonstrate the application of the method.