Denavit-Hartenberg

Denavit-Hartenberg

1. allows to establish the location of the reference systems of the links in the articulated robotic systems, whether prismatic or revolution, with open kinematic chains.

   • The process is...
     • 1,Laying out the reference frames
       • Number the joints from 1 to n starting with the base and ending with the end-effector.
         • Establish the base coordinate system. Establish a right-handed orthonormal coordinate system at the supporting base with axis lying along the axis of motion of joint 1
           • Establish joint axis. Align the Zi with the axis of motion (rotary or sliding) of joint i+1.
             • Establish the origin of the ith coordinate system. Locate the origin of the ith coordinate at the intersection of the Zi & Zi-1 or at the intersection of common normal between the Zi & Zi-1 axes and the Zi axis
               • Establish Xi axis. Establish or along the common normal between the Zi-1 & Zi axes when they are parallel
     • 2.Find the link and joint parameters
       • d: Depth alomg the previus joint z axis from the origin to the common normal
         • Theta: is the angle about the previous Z to align its x with the new origin
           • r: its the distance along the rotated x axis
             • alpha: rotates about the new axis x to put z into aligment with the axis of joint motion