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    1. DH Parameters (modified)

[Theory] [Intro to Robotics, Mechanics and Control] ch3

Manipulator Kinematics

DH Parameters (modified)

Procedures to set up frames all each joint:

  1. Identify the joint axes
  2. Identify the common perpendicular between them, choose its intersection with i-th axis as origin of {i}. (if parallel, any point can be chosen )
  3. Assign z along i-th axis
  4. Assign x along common perpendicular
  5. Assign y to complete a right-hand coordinate system
  6. Assign {0} to match {1} when the first joint variable is zero. For {N}, choose an origin location and x direction freely, but generally so as to cause as many linkage parameters as possible to become zero.

Parameters:

  • a: translate along x, align z
  • alpha: rotate around x, align z
  • d: translate along z, align origin
  • theta: rotate around z, align x

Transformation matrix formula see book (3-6)

Get forward kinematics formula by multiplying all transformation matrix together.