13 votes

What's the difference between a holonomic and a nonholonomic system?

For a nonholonomic system, you can at best determine a differential relationship between state and inputs. You cannot determine a closed-form geometric relationship. This means that the history of ...
SteveO's user avatar
  • 4,386
7 votes
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What does SE mean in robotics literature?

In that context, SE means "Special Euclidean" group, e.g. SE(3)* which is shorthand for "the special Euclidean group of rigid body displacements in three-dimensions". *Planning ...
sempaiscuba's user avatar
  • 1,054
7 votes

What's the difference between a holonomic and a nonholonomic system?

A holonomic constraint is a constraint on configuration: it says there are places you cannot go. That is a reduction in freedoms. That’s (usually) bad. A nonholonomic constraint is a constraint on ...
Franky's user avatar
  • 536
4 votes

What's the difference between a holonomic and a nonholonomic system?

Holonomic constraints are constraints that can be expressed in the form of an equation relating the coordinate of the system and time Non-holonomic are constraints that cannot be expressed in the ...
Gori Erick's user avatar
4 votes
Accepted

Are robot's codes usually compiled or interpreted?

Robots tend to be portable devices powered by batteries. Portable battery operated devices tend to use embedded processors with limited power and memory. Compiled code has several advantages over ...
st2000's user avatar
  • 496
4 votes
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Math behind trajectory planning

Since the problem is one dimensional, you are actually asking to compute a velocity profile. (A velocity profile is the information of how a path is traversed with respect to time.) Now the problem is ...
Petch Puttichai's user avatar
4 votes

What does SE mean in robotics literature?

It is a mathematical concept call the "Special Euclidean" group. Roughly, it is a combination of a rotation and translation. You'll also frequently see SO3, which is the special orthogonal group which ...
ryan0270's user avatar
  • 2,794
3 votes

What does SE mean in robotics literature?

$SE(3)$ is the representation for both translation and rotation in 3D space, whereas $SO(3)$ is only the representation for rotations. $\mathbb{R}^3$ is for translations in 3D space. If you only ...
kaixqu's user avatar
  • 31
3 votes
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State estimation of mobile robot

My solution is to use the following model with disturbance only at acceleration and curvature. $$ \begin{bmatrix} x_{k+1} \\ y_{k+1} \\ \theta_{k+1} \\ v_{k+1} \\ a_{k+1}...
evolved's user avatar
  • 218
3 votes
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Robot mechanism parts names

This is called a Stewart platform. You can use any linear actuator type, hydraulic, pneumatic or electric.
drerD's user avatar
  • 491
2 votes

Can I program my roomba to run essentially all day (except for charging, of course)?

If I understand you right, you want to achieve that three roombas clean 24 hours a day, just making a break if they need to recharge and then continue. The Create 2 is a roomba robot that is similar ...
SDwarfs's user avatar
  • 301
2 votes

Can somebody explain how these forward kinematics matrix equations were formulaed?

It looks (to me) like there's a typo in that answer. The approach is to recognize that you have to wind up at the same point, whether you get there via the left arm (d->e->blue dot) or the right arm (...
Chuck's user avatar
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2 votes
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how to implement trapezoidal velocity profile in code

Not sure how you're choosing to structure your code, but typically I'll have a master reference, in percent, and a rate limit, in percent per second. You can have different rates for acceleration or ...
Chuck's user avatar
  • 16k
2 votes

Basic question about Markov Localization, probability and belief distribution shift

Here is what I 'believe'. Lets make the diagram more labeled. Say door 1 starting from left most is at 4 meters from the origin at left, door 2 at 7 meters, door 3 at 15 meters. When the robot senses ...
Dhaval Ashokkumar Patel's user avatar
2 votes
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Basic question about Markov Localization, probability and belief distribution shift

The robot has sensed a door, so the initial belief distribution matches the three possible door positions. i.e. the only three places that it is possible for the robot to be in that scenario. The ...
sempaiscuba's user avatar
  • 1,054
2 votes

Basic question about Markov Localization, probability and belief distribution shift

I think this is just a way of illustrating the main idea behind the probability distribution and the representation is not complete. The idea is that there is a moment when the door is detected and ...
50k4's user avatar
  • 6,652
2 votes

How to convert vertical motion to horizontal?

This should have probably been a comment to @RobertEnglish answer ... but comments don't seem to allow pictures Bavel gears. Plastic ones should be rather inexpensive.
Vorac's user avatar
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2 votes
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Conveyor Belt Calibration for a Robot - Rotation Matrix

A general approach would be to construct a so called axis-angle representation and convert that to a rotation matrix representation. On order to do so, one could start with a normal vector of the ...
50k4's user avatar
  • 6,652
1 vote
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What is the type of electric motor that can lift 1.6 kg just like micro servos, but without the reduction gear?

One of the ways to calculate power is torque times speed. For a given mechanical power, you must reduce the speed to increase the output torque. When you say you want to keep the motor the same, keep ...
Chuck's user avatar
  • 16k
1 vote

How do you move large industrial robots?

As jsotola's comment suggests, this Q&A site cannot give you what you need, and the best we can do is likely to be opinion-based. Here are some things to try anyway. Keep reading this web site. ...
r-bryan's user avatar
  • 1,271
1 vote

How to handle robot movement close to coordinates x=0 with atan2

First off, your code may have some confusion about atan2, which already returns an angle between -pi and +pi. That's one reason to use atan2(dy, dx) instead of atan(dy/dx) -- it figures out the ...
r-bryan's user avatar
  • 1,271
1 vote

Rotate while strafing with mecanum wheels

Yes. A robot with 4 fixed mecanum wheels is able to translate and rotate simultaneously. There are many links online which provide tutorials on how to do this: https://www.instructables.com/Mecanum-...
Ben's user avatar
  • 5,825
1 vote

what are shoulder ball and socket joints called? (i am trying to design and build a hydraulic assistance mech suit)

A 2 degree of freedom shoulder joint can be called a gimbal or pan-tilt. It can be modeled with a universal joint (aka U-joint). Usually, the third degree of freedom to twist the arm can be added ...
Ben's user avatar
  • 5,825
1 vote

How to publish odometry from 3 wheeled omnidirectional robot?

It looks like you have most of what you need to output the Odometry message. The tutorial at http://wiki.ros.org/navigation/Tutorials/RobotSetup/Odom is probably the best practical resource. The ...
Tully's user avatar
  • 24.7k
1 vote

How to move robotic arm in straight line

First of all you should start to check 2 things: the angle $\alpha$ is given by some sensor the object and the path to the object (blue dotted line) both lie in the arm workspace If 1. is not met, I ...
N. Staub's user avatar
  • 1,402
1 vote

Are robot's codes usually compiled or interpreted?

Many people use Python to control robots. While it does use more computing resources to interpret the python code, it may take less time for the programmer to develop in an interpreted language. ...
NomadMaker's user avatar
1 vote

Estimating state of moving object from other moving object

It sounds like you can estimate everything you need to with a direct calculation of the transform between each vehicle since that is provided for you. For the derivative parameters, if your sensors ...
hauptmech's user avatar
  • 4,385
1 vote

Robot Veering to the Left

There are 4 possibilities: One of the wheels' centre is displaced slightly. Wheel encoders are not properly positioned and this is causing issues (like wheel pausing at odd positions while ...
Prasad Raghavendra's user avatar
1 vote

Robot Veering to the Left

Lets suppose, that left wheel is blocked, so nMotorEncoder[LM] is constantly zero, while nMotorEncoder[RM] counts something. ...
gilhad's user avatar
  • 453
1 vote

holonomic and non holonomic constraints in layman's term

A constraint on the $k$ coordinates $r_1,r_2,...,r_k$ is holonomic if it is an equality constraint of the form $$g(r_1,...,r_k)=0,$$ and nonholonomic otherwise. These sorts of constraints arise ...
JSycamore's user avatar
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