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
Messages
3
Reaction score
0
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 !
 
Engineering news on Phys.org
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.
 
Last edited:
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?
 

Attachments

  • Grasp matrix.jpg
    Grasp matrix.jpg
    7.3 KB · Views: 475
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
 
Posted June 2024 - 15 years after starting this class. I have learned a whole lot. To get to the short course on making your stock car, late model, hobby stock E-mod handle, look at the index below. Read all posts on Roll Center, Jacking effect and Why does car drive straight to the wall when I gas it? Also read You really have two race cars. This will cover 90% of problems you have. Simply put, the car pushes going in and is loose coming out. You do not have enuff downforce on the right...
I'm trying to decide what size and type of galvanized steel I need for 2 cantilever extensions. The cantilever is 5 ft. The space between the two cantilever arms is a 17 ft Gap the center 7 ft of the 17 ft Gap we'll need to Bear approximately 17,000 lb spread evenly from the front of the cantilever to the back of the cantilever over 5 ft. I will put support beams across these cantilever arms to support the load evenly
Thread 'What's the most likely cause for this carbon seal crack?'
We have a molded carbon graphite seal that is used in an inline axial piston, variable displacement hydraulic pump. One of our customers reported that, when using the “A” parts in the past, they only needed to replace them due to normal wear. However, after switching to our parts, the replacement cycle seems to be much shorter due to “broken” or “cracked” failures. This issue was identified after hydraulic fluid leakage was observed. According to their records, the same problem has occurred...
Back
Top