How to Derive the Grasp Transformation Matrix for a Three-Finger Robot Hand?

AI Thread Summary
The discussion focuses on deriving the grasp transformation matrix for a three-finger robot hand to effectively grasp a cube. The user is struggling with the calculation due to a lack of information regarding the rotation angles and the base frame's position and orientation. They provided three point vectors representing the grasp points on the cube but noted that additional details are necessary for completing the transformation matrix. The conversation includes references to resources on linear transformations and homogeneous coordinates, which are essential for understanding robotic transformations. Overall, the user seeks guidance on the steps to derive the grasp transformation matrix given the limited information available.
lwcjoseph
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Hello everyone, i am now working on a problem with three fingers robot hand to grab a cube to undergo some motion
however i face some difficulties on deriving the grasp transformation matrix which help to switching the local coordinate frame
at first i was given three point vectors [0 1 0]^T, [1 0.5 0]^T, [0 -1 0]^T (T means transpose)
then to calculate a Grasp transformation matrix
i would like to know the step to achieve the result and any general method for deriving the matrix?
thanks very much for your help !
 
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Read some of these introductions:

http://commons.bcit.ca/math/examples/robotics/linear_algebra/

http://elvis.rowan.edu/~kay/papers/kinematics.pdf

http://en.wikipedia.org/wiki/Transformation_matrix#Affine_transformations
http://en.wikipedia.org/wiki/Transformation_matrixI guess you are familiar with matrices to represent linear transformations like rotations.
The only special thing in these "robotic transformation matrices" is the use of a fourth "homogeneous" coordinate.
This allows to represent the group of rotations and translations at the same time, with matrices.
 
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i have read through the materials ,however, the angle of rotation and any other information concerning the transformation has not been given, that's why i have been stucked for so long
the result is as the pic attached
any help?
 

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lwcjoseph said:
at first i was given three point vectors [0 1 0]^T, [1 0.5 0]^T, [0 -1 0]^T (T means transpose)

Could you please answer these so that I can understand your question better?
Are these vectors the points on the cube that you need to grasp?
Do you have any information about the base frame and the position/ orientation of the hand?
 
yes they are the point that i need to grasp, however no other information are povided
that's why i have been stucked so long
 
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