Difference between revisions of "Notation of links, joints and coordinate frames"

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{{Navigation|before=[[Types of joints]]|overview=[[Denavit-Hartenberg Convention]]|next=[[Common normal]]}}
 
{{Navigation|before=[[Types of joints]]|overview=[[Denavit-Hartenberg Convention]]|next=[[Common normal]]}}
  
The notation of the links and joints is shown in the figure below. A manipulator consists of <math>k</math> links that are connected with <math>k</math> joints. The '''links''' correspond to the rigid parts of an arm and the '''joints''' are the flexible connections between them. A joint is always assigned to the proximate link. So a link <math>L_n</math> is connected with its joint <math>J_n</math> to the end of link <math>L_{n-1}</math>. The proximate link <math>L_{n+1}</math> is then mounted to the end of <math>L_n</math> via its joint <math>J_{n+1}</math>. The first link <math>L_1</math> is mounted on the base via joint <math>J_1</math>. So the base is actually link <math>L_0</math> but does not directly belong to the manipulator. The end of the last link <math>L_k</math> corresponds to the end-effector.
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The notation of the links and [[Types of joints|joints]] is shown in the figure below. A manipulator consists of <math>k</math> links that are connected with <math>k</math> joints. The '''links''' correspond to the rigid parts of an arm and the '''joints''' are the flexible connections between them. A joint is always assigned to the proximate link. So a link <math>L_n</math> is connected with its joint <math>J_n</math> to the end of link <math>L_{n-1}</math>. The proximate link <math>L_{n+1}</math> is then mounted to the end of <math>L_n</math> via its joint <math>J_{n+1}</math>. The first link <math>L_1</math> is mounted on the base via joint <math>J_1</math>. So the base is actually link <math>L_0</math> but does not directly belong to the manipulator. The end of the last link <math>L_k</math> corresponds to the end-effector.
  
 
There are <math>k</math> '''coordinate frames''' defined for the <math>k</math> links of a manipulator plus one base or reference frame, respectively. The coordinate frames are always attached to the end of the links at the distal joints. The first coordinate frame, indexed <math>K_0</math>, is the base or reference frame and attached to the base in joint <math>J_1</math>. The next frame is <math>K_1</math> at the end of link <math>L_1</math> in joint <math>J_2</math> followed by <math>K_2</math> at the end of <math>L_2</math> and so on. The coordinate frame <math>K_k</math> of the last link is finally attached to the end of of the manipulator and so to the end-effector.
 
There are <math>k</math> '''coordinate frames''' defined for the <math>k</math> links of a manipulator plus one base or reference frame, respectively. The coordinate frames are always attached to the end of the links at the distal joints. The first coordinate frame, indexed <math>K_0</math>, is the base or reference frame and attached to the base in joint <math>J_1</math>. The next frame is <math>K_1</math> at the end of link <math>L_1</math> in joint <math>J_2</math> followed by <math>K_2</math> at the end of <math>L_2</math> and so on. The coordinate frame <math>K_k</math> of the last link is finally attached to the end of of the manipulator and so to the end-effector.

Revision as of 17:48, 10 November 2015

← Back: Types of joints Overview: Denavit-Hartenberg Convention Next: Common normal

The notation of the links and joints is shown in the figure below. A manipulator consists of k links that are connected with k joints. The links correspond to the rigid parts of an arm and the joints are the flexible connections between them. A joint is always assigned to the proximate link. So a link L_n is connected with its joint J_n to the end of link L_{n-1}. The proximate link L_{n+1} is then mounted to the end of L_n via its joint J_{n+1}. The first link L_1 is mounted on the base via joint J_1. So the base is actually link L_0 but does not directly belong to the manipulator. The end of the last link L_k corresponds to the end-effector.

There are k coordinate frames defined for the k links of a manipulator plus one base or reference frame, respectively. The coordinate frames are always attached to the end of the links at the distal joints. The first coordinate frame, indexed K_0, is the base or reference frame and attached to the base in joint J_1. The next frame is K_1 at the end of link L_1 in joint J_2 followed by K_2 at the end of L_2 and so on. The coordinate frame K_k of the last link is finally attached to the end of of the manipulator and so to the end-effector.

Links.png