DenavitHartenberg parameters
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When the coordinate frames are assigned to a manipulator, the transformation between each two consecutive frames has to be described. As before for the assignment of the coordinate frames, the manipulator has to be in its zero position as well for the determination of the parameters. The figure on the right shows the two coordinate frames and in their zero position and the corresponding common normal represented by a dashed red line. To describe the transformation of with respect to , the 4 DenavitHartenberg parameters , , and are used. These parameters describe the static transformation within link , but as well include the dynamic influence of the joint parameter of , that could change over time. The figure illustrates the parameters, that are defined as follows:
The angle is defined as the angle about the axis to align with the new axis.
 
is the offset or translation, respectively, along the axis from the origin of to the intersection with the common normal.
 
The parameter corresponds to the translation along the new axis. The translation distance is equivalent to the length of the common normal. It has to be kept in mind, that and the common normal can be antiparallel and that, in such cases, a positive translation is directed in the negative direction of the common normal. If the related joint is a revolute joint, can also be regarded as the radius of the rotation about the axis  
The angle corresponds to the angle about the new axis, which is collinear to the common normal, to align the axis with the new axis. So the rotation direction for positive angles depends on the direction of . 
 Placement in the context of transformations
 The 4 parameters can rather be determined by just regarding the two coordinate frames, their axes and the common normal like visualized above. To completely understand the parameters and their meaning, the figure below illustrates what the parameters actually describe. , , and define 4 transformations that are applied consecutively to transform the coordinate frame to . First a rotation about the axis by is applied followed by a translation along the same axis by . Then the coordinate frame is rotated about the axis by . Finally a translation along the axis by leads to the next coordinate frame . Some further aspects about the meaning and the use of the 4 parameters are described in the following article about the Amatrices.
The videos at the end of this page explain the assignment of the coordinate frames and the determination of the 4 parameters very vividly and comprehensibly.

Example: Determination of the DenavitHartenberg parameters
The table below contains the DenavitHartenberg parameters for the manipulator shown in the figure on the right. For further information about the already assigned coordinate frames, have a look on the examples of the previous articles. The necessary lengths of certain parts of the manipulator are indicated by the variables to .
Considerable aspects of this manipulator are:

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