# Tag Info

Accepted

### Hand Eye Calibration

After solving the problem, I created a keynote presentation explaining many details about hand eye calibration for those that are interested. Practical code and instructions to calibrate your robot ...
• 486

### What is the technology used for no-resistance robot arms?

It's called compliance. Gravity compensation by itself is not enough to achieve this, as well it is not mandatory. For example, if reducers with high reduction ratios are used, robot arm will be very ...
• 241
Accepted

### How to create a Industrial Robotic arm controller?

Industrial robots (e.g. Kuka, ABB, Fanuc) use a control cabinet which has the following main components: Drive amplifiers (controllers): The drive amplifiers are responsible for the closed loop ...
• 6,322
Accepted

### Designing a 5 bar linkage robot: Plot Clock

Both the forward kinematics and inverse kinematics aren't too difficult, but always a little tricky for parallel manipulators like this one. Consider the configuration in this diagram. The forward ...
• 1,357

### Why don't cheap toy robotic arms move smoothly?

The reason the robotic arm that you linked to does not move smoothly is that the commands given to it are not smooth. That type of actuator does not have any internal logic to generate a smooth motion ...
• 4,205
Accepted

### Impedance Control vs Position Control

In classical position control, the feedback controller only cares about the position error and is tuned to minimize it. This is done by using very high gains, i.e. if there is even a small position ...
Accepted

### Is there a way to determine which degrees of freedom are lost in a robot at a singularity position by looking at the jacobian?

Not by merely looking at Jacobian but by looking at the Singular Value Decomposition of the Jacobian, one can see the degrees of freedom that are lost, if lost. Of course it technically somehow turns ...

### How high of a gear ratio can a motor have?

Your calculation of about 80 N⋅m torque for lifting 8 kg with a 1 m lever arm is ok; more precisely, the number is 8 kg ⋅ 9.81 m/s² ⋅ 1 m = 78.48 N⋅m. As mentioned in other answers, you will need to ...
Accepted

### Why do we generally prefer DH parameters over other kinematic representations of robot arms?

I have been doing a lot of reading up on kinematic calibration and here is what I found: From [1]: A kinematic model should meet three basic requirements for kinematic-parameter identification: ...
Accepted

• 609

### jacobian of Abb irb140 robot

Here is the traditional way. I think this is the kinematics of your arm, but am not 100% sure. Here are the DH parameters and transformation matrix: DH Parameters for the anthropomorphic ...
• 5,215
Accepted

### Industrial Robotic Arm

2 kgs is not very much, so i would probably consider arms that are slightly less industrial than Kuka, ABB, Fanuc, Denso and the like. However, 1.6m is pretty long and that may be hard to find in non-...
• 5,215
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### What type of servos are used in industrial robot arms like Universal Robot UR5?

Universal states that they use brush-less DC motors with harmonic drives on their FAQ here http://cross-automation.com/blog/universal-robots-top-10-faqs Bigger ones like the KUKA KR5 uses AC servo ...
• 241

### Design and construction of universal robotic arm (5kg, 1m)

To answer your questions about the motors/gearing: To lift 5Kg at 1 metre distance - the "shoulder" torque needs to be 500 Kg.cm or about 5000 N.cm. This is far above the torque of most model servos,...
• 1,001

### KUKA Robotics API IDE

If it's your first time, better off try with a simulator to check that your program doesn't break the robot's constraints or security configurations. The most powerful simulator I came across is "V-...
• 168
Accepted

### Comparing industrial robot arms

For example, how does price vary with precision, speed, reach and strength? The price vary a lot, from a couple of hundreds of bucks to hundreds of thousands of dollars ( Willow Garage's the one-...
• 168
Accepted

### What is the required theory behind building a robotic arm?

There are 2 (or 3, depending on how the planned lifetime of the robot is) thing thats you have to consider. Static load: The motors stall (zero revolution) torques have to be able to hold the weight ...
• 6,322