# Tag Info

### Rotation matrix sign convention confusion.

I think that the main issue is that you're trying to read your rotation matrices from left to right. The sign changes seem random, but actually cycle in an ordinary way. Below follows a more elaborate ...
• 552
Accepted

### Why do current manipulators tend to use 7 DoF instead of 6 DoF?

Adding a 7th joint, and still targeting a 6D pose, would result in a null space of at least one dimension anywhere in the workspace. That is basically one the reasons people may wish to use a 7-DOF ...
• 306

### Computing inverse kinematic with jacobian matrices for 6 dof manipulator

Disclaimer! I will try to solve your problem but it may or may not solve the problem with your code! TL;DR: Two possible mistake in your code. In your pseudo-code, you are using transpose of ...
• 226

### Forward kinematic and inverse kinematic... When to use what?

Forward kinematics uses joint angles (with known link lengths) to compute the tool position and orientation. Inverse kinematics uses tool position and orientation, to compute joint angles. Note: if ...
• 4,326
Accepted

### Forward kinematic and inverse kinematic... When to use what?

Let me give you a mathematician's perspective on the difference between the two kinds problems. Forward kinematics asks the question: given a certain input (i.e. control command), what will be the ...
• 1,238
Accepted

### Is the geometric inverse problem's solution "continuous" for a redundant robot?

I don't know if there is a formal proof to this, but in general, no the set of all possible joint configurations that correspond to a particular end-effector pose is not continuous. I think of the ...
• 5,215
Accepted

• 4,205
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### How do I find the inverse kinematics of a 5-DOF manipulator having the following DH parameters?

A general IK solution is not possible for an arm with less than 6 joints. You can move the gripper to any point (within reach) but you can't completely control the orientation. If you fix the ...
• 1,522

### Inverse kinematics for differential robot knowing linear and angular velocities

Your linear velocity should be the average of both wheel values. Assuming there's some wheel radius of WHEEL_RADIUS, as you've stated, then you should get each ...
• 14.6k

### Can workspace of a manipulator change after considering its dynamics?

The workspace of a manipulator is strictly determined by its kinematics. Since kinematics only consider the geometry of motion, without regard to forces and torques needed to accomplish tasks, you ...
• 4,326
Accepted

### Solving inverse kinematics with non-linear optimization libraries

Is it a good idea to solve inverse kinematics with non-linear optimization libraries such as Ceres? Yes, definitely! The trend in literature during the last years is to walk away from the traditional ...
• 3,490

### 7DOF inverse kinematics spherical wrist

I believe kinematic decoupling used to be the standard procedure for 6 DOF arms. (6R with spherical wrist). Where you would solve the 3 DOF position IK first, then 3 DOF orientation IK. If you ...
• 5,215