Manipulator Joint and Arm Structure

Link: Individual rigid sections that make up a mechanism are called links. 

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These can be summarized under two types of joints: linear and revolute. In the table above, the first two joints are linear joints and the last three are revolute. 

Degrees of Freedom and Manipulator Workspace

The degrees of freedom (DOF) of a robot manipulator or mechanism is the total number of independent variables that can completely identify the configuration of the manipulator mechanism in the space. The following robotic arm has 2 DOF:

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