# Questions tagged [inverse-kinematics]

Inverse kinematics is a subtopic of kinematics dealing with equations that describe the joint parameters necessary to move a robotic arm to a particular position. Also called motion planning.

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### Calculating the singular configuration of a 3 revolute joint manipulator

I would really appreciate it if somebody could help me calculate the singular configuration of this simple manipulator I am confused since J is a 2x3 matrix and I cannot simply calculate the ...
165 views

### Visual servoing - tracking a point

I am trying resolve some issues i am having with some inverse kinematics. the robot arm i am using has a camera at the end of it, at which an object is being tracked. I can from the the camera frame ...
282 views

### Processor and command interface preference for a robot arm

I want to build a robot arm that'll be approximately 1.25 meter long and will be able to lift up to 2 kilograms. It'll have 6 dof and it is an expensive project. And most importantly, i am the only ...
334 views

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

I have a differential robot and I am using ROS to run it. When I need to move the robot, I can send commands to it, specifically linear X and angular Z velocities. Linear X is in m/s whereas angular Z ...
303 views

### What is difference between 2 wheels and 4 wheels and tracked differential mobile base kinematics?

In generally I know that no difference between 2WD and 4WD mobile base control kinematics equations. but is there really difference between two wheels differential mobile base and tracked/...
402 views

### Orocos KDL issue with Rotation (matrix) - Inverse Kinematics

I have a problem with the Orocos IK solver, especially with the KDL::Rotation matrix input. I try to call my KDL IK solver with a normal vector and a rotation. If I use the example values for the ...
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### List of books similar to Thrun's Probabilistic Robotics for robot mechanics and manipulation [closed]

What? Put together here a list of books (like the one for C/C++ on StackOverflow) that are spiritually similar to Sebastian Thrun's Probabilistic Robotics for robotic manipulation and mechanics. Why?...
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### Assuming I have the angle with respect to two beacons, and know the distance between them, can I localize myself?

Let's assume I have the following situation, and need to find (x,y). Is it possible? There does not appear to be more than one solution to the system, but my trigonometry is a bit rusty. I feel ...
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### Jacobian transpose: how to calculate orientation error

I'm confused about how to compute the error in orientation. All the documents I've read don't explain how to do it. The error in position is simply the difference between the points. Let's assume ...
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### How to find the body jacobain, for each link in a robot manipulator?

The links twist could be obtained, and thus The spatial manipulator Jacobian could be done, but when it comes to the body Jacobian, it is becomes difficult. Moreover, the adjoint transformation ...
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### Inverse Kinematics in Java

I'm planning to write an Inverse Kinematics controlled 6 dof virtual robot for Android. I did some research on packages avaliable and couldn't choose the right one which will satisfy my needs on this ...
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### Jumping motion in point to point movement

I have one question about point to point movement. Let's say the end-effector is placed at $(0,0,0)$ and the goal position is at $(10,0,10)$. The corresponding joint angle value changes $d\theta$ can ...
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### Help understanding decoupled inverse kinematics

I've been researching decoupled inverse kinematics with respect to industrial robots. The assumptions made in the decoupled equations greatly simply the equations, however I am having a hard time ...
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### Number of inverse kinematics closed form solutions for ABB IRB 140

I've read that 6 dof manipulators give eight closed form solutions, according to a paper. What is the number of iK solutions for the ABB IRB 140? (last three axes intersect but there is a offset ...
286 views

### Inverse kinematics with end effector orientation?

I'm trying to implement an inverse kinematics solver, but this time even with the end effector's orientation. I succeeded with the case when the end effector only requires the position. I learned ...
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### Position Sensor

During my design of a simple robotic arm, where I 3D printed most of the parts, then used these HS-422 servos, it turned out that for a better control precision and to be able to apply Inverse ...
633 views

### Understanding inverse kinematics with the Jacobian

I'm learning about inverse kinematics with Jacobians, and getting a little confused. So, let's say I have a robot arm with two joints with angles Y = (a, b) whose ...
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### Very slow calculations of link orientation for 6DOF IK

I have written a matlab code to solve IK for 6 DOF robotic arm. I use Newton method to numerically solve IK. Also i use Tikhonov regularization to hand bad conditioned Jacobians. It works fast and ...
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### Negative torque and negative velocity during reverse dynamics in Matlab Robotics Toolox.

I'm using Robotics Toolox Matlab and I did Reverse dynamics using code below. ...
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### Off position robot model - Inverse Kinematics

I had to make a Unity3D robot model(ABB IRB 1600-6R/6DOF), that given a desired end effector transformation matrix, it would calculate and rotate the robot joints to the appropriate angles(Inverse ...
367 views

### Rostock Delta Robot 3D Printer Degrees of Freedom (DOF)

What is the degrees of freedom (DOF) of the Rostock delta robot 3d printer (delta mechanism that consists of three prismatic joints)? Here's the link to the delta mechanism I'm referring to: https://...
894 views

### Inverse Kinematics Constant End Effector Angle

I have a simple RRR manipulator where one motor controls the base rotation, and the other two allow movement in a plane extending forward from the base and upwards/downwards. Are there any standard ...
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### Inverse kinematics of a sun tracker with swapped axes

I am realizing a sun tracker based on latitude, longitude, and date-time. The system calculates the azimuth and elevation angles to track the sun. In a classic sun tracker, the azimuth axis is ...
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### Inverse Kinematics of Puma 566 giving low angle results with DH convention

I am new at the robotics area, and i need to deliver an activity until this week in my college based to solve the inverse kinematics problem from an article that doesn't have any code done, and after, ...
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### Parallel Inverse Kinematics for Multithreaded Architecture (or GPU)

Here, you can find a nice academic paper about this topic. What I am looking for it is a real implementation of it or, instead, any other implementation of IK algorithm that can run in a many-core or ...
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I and my friends are planning to build a dog like quadruped robot. We have designed it like MIT Cheetah Mini like legs structure, each leg having 3 Servos, 3rd DOF for rotation. We have calculated ...
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### Path Planning for Spherical Wrist (RRR)

I have found the inverse kinematics of a spherical wrist. The wrist is not attached to any other type of arm, it is the sole controller. Based on this IK solution, how can I generate a path plan for ...
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### help to find the bug for calculating inverse kinematic using jacobian

I am calculating inverse kinematic for 5dof robotic arm using Jacobian matrix (first time). i used following formulas to do my calculation and also implemented in my code. for more information please ...
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### how to normalize PWM if the value exceeds the maximum speed limit

I have implemented inverse kinematics for nonholonomic mobile wheeled robots, and the RPM range of the motor that I used is -50 to 50, while for PWM is from 1300 to 1700. But in certain cases, the RPM ...
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### How to implement end effector orientation in generic IK solver

I am trying to script a basic, lightweight IK solver with a Jacobian Transpose method. I have gotten a basic script that reach the desired position very quickly. What I am not able to do is achieve a ...
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### python code for closed form inverse kinematics solution

I solved the inverse kinematics of a 4DOF robotic arm (which is not planar) and I wrote this code bellow in python. The coordinates for each joint is: I considered the first three joints as a wrist ...
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### Find out Robot Coordinate using odometer data

I have a data set name Robot_odometery which consist of 3 field namely, Time(s),Forward velocity(m/s) and angular velocity(rad/s). I taken this dataset from http://asrl.utias.utoronto.ca/datasets/...
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### Beginners guide to Inverse Kinematics for biped robots? [closed]

I'm building a LynxMotion Scout biped and believe that IK are the best way to develop an effective gait. I'm a mechanical design engineer - I currently have minimal skills / experience with ...
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### Inverse kinematics for a robot lamp

I've been working on a robot lamp. Looking something like this: So i had a few questions. I've decided to simplify the movements by giving the head a fixed orientation like you see in the picture. ...
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### BiRRT: Getting path from an array of 7 DOF angle configurations

I've kind of finished implementing a BiRRT for a 7 DOF arm, using a KD-tree from numpy.spatial in order to get nearest queries. A picture is below: I'm currently having trouble with the fact that it ...
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### Power Model for humanoids

I am in the process of creating a Power Prediction Model for the Hubo Robot. The Robot has 38 Degrees of Freedom and has a computer some sensors and motor boards. The motors are powered through Motor ...
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### How do I find the inverse kinematics of a 5-DOF manipulator having the following DH parameters?

alpha = [ -90, 0, 0, 90, 0] a = [ 0, 400, 200, 0, 0] d = [63.5, 0, 0, 90, 100] I am trying to calculate the joint angles but I am stuck ...
217 views

### Inverse Kinematics problem formulation (optimization)

Note:Q is a diagonal posituve semi-definite matrix Why is the IK formulation like that? It looks like it's trying to find the optimum dq/dt that will minimize the magnitude dq/dt. How is that giving ...
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### Is there any C++ library I could use to program a robotic manipulator involving forward and inverse kinematics?

I came across robotics library (RL), but quite unclear about its real purpose. Is it a FK/IK solver library or simply an graphical simulator?. RL has poor documentation, so its not clear how to use it....
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### Finding center of mass and support polygon for quadruped robot

I intend to find the center of mass of a quadruped robot and find the convex of the CoM inside the support polygon. I want to make a model of this, which is further going to help me develop stable ...
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I am currently designing a 2D simulation of a 3DOFs robotic arm in order to develop a better understanding of inverse kinematic (so as to avoid breaking more components than necessary) but despite my ...
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### Inverse Kinematics “Can not converge” issue

I'm a complete beginner with LabView and I have been practicing forward kinematics with the help of a tutorial I found. It's been a learning curve but I've managed to understand a few things. However,...
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### Solving Inverse Kinematics with unknown orientation

This may be a very basic question, but I haven't had much success finding an answer. I'm currently trying to solve the inverse kinematics of a 3-RRR Planar kinematic arm, whose purpose is to move ...
835 views

### forward and inverse kinematics of arm

I'm trying to figure out to a problem with a planar manipulator. The manipulator has a base effector and L1 and L2 with 3 joints. Question: INVERSE KINEMATICS Given the ...
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### Inverse kinematics for a four-legged robot

I want to make a 4 legged robot like spider or dog, but I don't know how I can use kinematics to make it walk and run. I didn't find any resource to know how these types of robots walk and run by ...
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### Robot Arm Simulation

I don't know if this is the right place to ask this question but I'll give it a try. A friend of mine is using unity 3D to simulate a robot arm, however he's having some troubles when he needs to ...
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### Robotic Manipulator [closed]

I have started working on robotic manipulators and got into a project which deals with control of robotic manipulator using artificial neural networks (solution of inverse kinematics and trajectory ...
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### Finding cubic polynomial equation for 3 joints

My professor gave us an assignment in which we have to find the cubic equation for a 3-DOF manipulator. The end effector is resting at A(1.5,1.5,1) and moves and stops at B(1,1,2) in 10 seconds. How ...