Then, the matching crank-rocker module is designed to be supplemented to the four-bar with a revolute joint
at the circle point.
Note that, for the RPU limb, the axis of the revolute joint
connected to the base platform is parallel to the y axis and the axis of the universal joint connected to the moving platform is also parallel to the y axis.
The shoulder joint has 3 DOFs (S1: abduction/adduction; S2: flexion/extension; S3: rotation), and the elbow is simplified as a revolute joint
with 1 DOF (E1: flexion/extension).
Similar to the lower-limb straight-walking assistive robots in [16, 17], in this paper, the lower-limb straight-walking assistive mechanism also only assists hip joint's and knee joint's flexion/extension motions, where the assistive mechanism includes a revolute joint
and a prismatic joint as shown in Figure 1.
For front suspension, two under-springs were connected with each tire and wheel by revolute joint
and these two under-springs were connected with vehicle body by translational joints.
Each joint is a revolute joint
and controlled using a servomotor.
are represented by blocks 'Revolute joint
', which permits rotation about its Z-axis.
Fork is connected to the handle through a revolute joint
, so that its angle with the handle may be changed.
Comparison of revolute joint
clearance model in the dynamic analysis of rigid and elastic mechanical systems, Mechanism and Machine Theory 37(9): 895-913.
The elbow DOF consists of a revolute joint
that is actuated by a brushed motor attached via nylon coated cable to a capstan arc.
It is formed by reduction of one coaxial revolute joint
into one kinematic chain which makes a parallel-plane moving.
For the prismatic joint, [d.sub.i] is the variable whose value range is [d.sub.i] > 0, while for the revolute joint
, [[theta].sub.i] is the variable whose value range is -[pi] ~ [pi].