Parallel Manipulators

Industrial robots are generally of the serial type, i.e., they are open kinematic chains. This class of robots produce several drawbacks. Due to the cantilever-type of construction, their positional accuracy is low. Parallel robots are closed loop manipulators. Their load-carrying capacity is higher since most of their drives are fixed on the ground. Since power transmission is eliminated or reduced, accuracy and reliability of operation are increased.
Applet for the Simulation of a 3-DOF Planar Parallel Robot

Limiting values for the parameters:

Parameter Limiting Value Default Value
End-effector plate length 50 - 100 100
Angle of inclination of End-effector plate 0 - 180o 0o
Length of Link 1 60 - 100 100
Length of Link 2 50 - 100 100
Length of Base Triangle 150 - 300 300

Notes:
  • The orientation of the end-effector plate is fixed as 0o.
  • When the two links of a particular leg fall on a straight line, it is considered as a Singular Pose. Other instances of Singularity are yet to be implemented.
  • The program checks for Reachability of each pose before simulating the motion.
  • Inverse Kinematics of each leg has been used for finding the Joint variables.
  • The "Speed" variable given in the applet is for changing the speed of animation based on the processor on which the applet is seen.
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