# Tag Info

3

In an ideal scenario, yes, that should be the case. When gravity compensation is implemented on robots, all joints apply a torque to balance out the torque applied by the force of gravity. They should ideally turn into floating robots objects. However, it is not always the case due to inaccurate modeling and gravity compensation implementation. Moreover, to ...

3

Considering your apparent education background, I’m surprised at this question... But regardless. Working with robots, when compared to making robots are very different things. This is not so much different than driving cars and fixing them compared to designing and building them. As you studied physics, then you’re well aware that physics is the ...

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You write down the kinematics of your robot as a series of simple transforms, translations and rotations. In MATLAB this would be: >> s = 'Rz(q1) Tz(L1) Tx(L2) Ry(q2) Tz(L3) Ry(q3) Tz(L4) Tx(L5) Rx(q4) Tx(L6) Ry(q5) Tx(L7) Rx(q6)'; in words: rotate about the z-axis by q1, translate in the z-direction by L1, translate in the x-direction by L2, rotate ...

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Solved ! No need to connect a keyboard. I went to D:\cmafiles\STATS and there is the whole list of files with the working statistics in XLS format. I've copied all of them on my USB Flash memory. Thank you everyone.

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Actually, in certain configurations you can have an infinite number of IK solutions. For example if joints 4, 5, and 6 are straight and inline as in your image. You can rotate joint 4 by $X$ and 6 by $-X$ to get the same end-effector pose. This is a great video on arm singularities which also shows this phenomenon nicely: https://www.youtube.com/watch?v=...

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CAD software knows everything about your parts...(assuming you tell the things it doesn't know...as mentioned, material properties) After doing this, calculating multibody C.O.G or even inertias of complex bodies is 'trivial' (of course, it wasn't for the programmers). These things can be very accurate, or can be made very accurate, however they can and ...

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It is approximate and very accurate as long as the material properties are well defined. Many methods are combined to get it. Moment of inertia, parallel axes, mass distribution, etc etc. Simplification methods are implemented to make the computations efficient. All the bodies are simplified as well using triangles to make them convex.

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The problem in both cases is to move the robot tool to some pose relative to an object. Let's assume the camera is attached to the end of a robot arm (eye in hand case) so we will consider this a problem in moving the camera. The tool will always be at a fixed relative pose to the camera. In PBVS we uses a geometric model of the object, plus known camera ...

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What you're trying to do is also known as Visual Servo. You could do it only with the position of the object, but it's normally not done this way because without the rotation information, you cannot guarantee Force nor Form Closure, which is what you need if you don't want to drop your object, be it because of external forces, slippery, etc. You first need ...

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The API doesn't have any direct support for endian conversion / byte-swapping. However, there are some Java functions that can handle it: Short.reverseBytes(short i16) Integer.reverseBytes(int i32) Long.reverseBytes(long i64) So, the calls in the question would become: controller.setOutputGroups(outNum, 2, Short.reverseBytes(value16bits)); controller....

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This is a limitation of DH notation. Axis rotation follows the right-convention about the z-axis. For the first joint you are stuck with rotation about the world z-axis, hence your problem. For the Robotics Toolbox joint rotation all follow the right-hand convention. You could multiply your joint angle vector by a vector of rotation directions dir = [-1 ...

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The V-Rep simulator can use a few physics engines that have some soft-body support, including: Vortex Dynamics (commercial) which has some soft-body support for specific cases The Bullet Physics Engine (FOSS) which has support for soft-body simulation (though it isn't supported in the current version of V-Rep)

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