Hello to all...
I found post on the forum for angle conversion between euler and quaternions.
bit confusion if someone guide me.. From CAD drawing if i get angle between two points is 30 degrees.
How i ll convert it into quaternions.. 30 degree is from reference to the gap between two points (an ARC). how to tell robot what will be orientation when reached at 2nd point.
regards
Quaternions
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sikander bakht -
April 12, 2022 at 8:48 PM -
Thread is Unresolved
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More information are very welcome!
Do you have an example explaining your problem?
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yes sir,
in fact i have a rotary positioner (to clamp the job and rotate the job before robot for angular machining (drilling). The positioner got faulty and i have to drill the job, controlling the tool orientation to maintain straightness of to0l with respect to robot.
The angle can be calculated from cad drawing of job (that is the distance between two holes). i need this angle value from cad, converted in a form so abb robot understand this and take it as orientation value Q1,Q2,Q3,Q4. the robot will adjust its orientation based on these quaternion value...
regards.
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What angle can be calculated from cad drawing and how.
A sketch could be useful (showing the different coordinate systems
you can also check this out
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The system functions OrientZYX and PoseMult may be part of what you need.
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The problem is CAD.
KUKA and ABB have the same sequence of rotation (TB: Z,Y,X). And this leads to a specific calculation of w,x,y,z
The problem is how to get the angle from the cad system (maybe name of cad system could be helpful)
On the other hand ABB can also use angles instead of quaternation (check documents!)
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check this
I also created a tool to do all the calculation:
According to quaternation:
UR and ABB could be the answer
Have a look to here
Actually SkyeFire never answered
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Actually SkyeFire never answered
I've been busy!
It's still on my to-do list, honest!
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@ MOM & SkyeFire ,Thanks for the help and time.
Sorry for being late.. I was suffering from fever..
The scenario is i have to drill a semi-circular plate that is clamped on a fixed table.
defined a new workobject for this table and shift zero point of robot to the table..(0 point at center of the table).
Use AutoCad software to design table and semi circular plate models with same physical dimensions to avoid any error.
reference of actual system and CAD designed system is same now. In autocad i just calculated the coordinates values from center position to the Plate (Plate is clamped to the table at 90 degree).
Use the coordinates as Robtarget, drilled first hole, that is fine.
"As the plate is mounted on static table, for the second drill the robot has to re-orient itself with respect to the hole position just to avoid drill bit breakage, came in contact with plate at 90 degree to have a good drill' .
This re-orientation of the tool with respect to plate, i calculated as gap between two holes and angle from the reference position "a Semi circular arc". it comes to me with spherical coordinates "Theta, Phi and r"
i want to feed as Rot.q1, Rot.q2, Rot.Q3, Rot.Q4, so the robot align itself for the next hole itself .
hope i explained it well..
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SkyeFire using euler angles or quaternions in robtarget rot.q1 ,q2,q3,q4 will generate orientation for the robot automatically or OrientZYX have to use in separate
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i am studying also for the frame transformation. Rotation matrices of Rz(Sci), Ry(theta) and Rx(Phi). how to transform spherical angle into euler angles.
I also used CREO to verify the design, dimensions and angle calculations..
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This re-orientation of the tool with respect to plate, i calculated as gap between two holes and angle from the reference position "a Semi circular arc". it comes to me with spherical coordinates "Theta, Phi and r"
i want to feed as Rot.q1, Rot.q2, Rot.Q3, Rot.Q4, so the robot align itself for the next hole itself .
hope i explained it well..
Honestly, I don't understand why your CAD file cannot simply provide the coordinates in XYZ from a common reference point. Why spherical angles?
If all the drill positions lie on a circular arc, then creating a Work Object at the center of the arc, with one axis (Z would be most convenient) perpendicular to the surface of the plate, might work. It would be necessary to teach the first drill point by hand (referenced to the Work Object), but after that, simply rotating the Work Object around Z (using OrientZYX and PoseMult) by the correct angle, and repeating the program, should work fairly well.
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CAD can give XYZ Coordinates also. For linear drill i used that so many times.
Rotary Positioner is damaged and i have to perform drill with job clamped on static table as work object is the thing that creates the problem, to orient the drill straight at every hole position. I ll use OrientZYX to check the euler angles at 2 ,3 different points manually , on semi circle. Then will keep the angle constant around a profile.
Thanks for the help Sir...