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8 votes
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Can a state matrix have a row of zeros?

Yes, a state matrix with zero rows and/or columns makes sense and is viable. It typically signify pure integrators in the system. In the example you give, $$ \dot{v} = -\frac{b}{m} v +\frac{1}{m} u ...
Christo's user avatar
  • 385
7 votes

Sphero's logic, how does it work

The principle lying underneath the sphero robot's design and locomotion is shifting of the centre of mass of the ball and making it unstable which makes the ball roll [1,3,4,5,6]. A controlled and ...
bluebird's user avatar
  • 173
6 votes

Inverting a transform (Reading J Craig's book on Robotics)

Given that an homogeneous transformation $T \in SE\left(3\right)$ can be expressed as $$ T= \left( \begin{matrix} \mathbf{R} & \mathbf{p} \\ 0 & 1\end{matrix} \right), $$ where $\mathbf{R} \in ...
Ugo Pattacini's user avatar
5 votes
Accepted

What is torque bandwidth in actuated joints and how does it affect the control systems?

The torque bandwidth is typically referring to the maximum frequency of motion at which the actuator can provide that torque. So your actuator can provide a peak torque of 100 Nm, as in it can hold up ...
Brian Lynch's user avatar
  • 1,377
5 votes
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How important are events like "Robocup" to the advancement of Robotics in general?

Robotics is a relatively new field of study. Besides technological problems, there are psychological and even moral issues that need to be resolved. Some examples of these non-technological issues ...
Shahbaz's user avatar
  • 3,230
4 votes
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Quadcopter frame design

A frame in that configuration or any other witch holds the props in a square without being unbalanced would work, the reason that most people do it with cross bars is because the FC batteries and ESCs ...
Mark Omo's user avatar
  • 1,909
4 votes
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How to get manufactured part from CAD file?

I think this is a great question. The two basic options are make it yourself or have someone else make it. EDIT: check the bottom for a third option... Make it yourself To make it yourself you ...
hauptmech's user avatar
  • 4,335
4 votes
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Is it better to use software or hardware for object sorting?

It really depends on the objects you are sorting, and the flexibility you're looking for as the system is maintained over the years. Using physical methods to sort is very reliable. Many times you ...
SteveO's user avatar
  • 4,376
3 votes
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Create 2 CAD files

The CAD you pointed out is for the Turtlebot, and includes electromechanical CAD for that assembly. I only spot-checked a few files, but the only Create-relevant CAD in that package I found was an STL ...
Steve's user avatar
  • 952
3 votes

idea for web application in robotics

web based robotic simulator will be a good project. You can do simulators like gazebo and morse
acs's user avatar
  • 1,104
3 votes
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Stewart platform as robotic wrist joint

The "best" robot wrist in terms of human analog is probably the omni-wrist by Mark Rosheim. It has a large range of motion, and does not have singularities or gimbal lock that plague other more ...
Ben's user avatar
  • 5,780
3 votes
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Verifying motor selection calculations

I think your Pmotor calculation is correct. The reason for the difference with the CIRC link is in the P=F*v equation they are referring to the linear velocity. Your conversion is converting the ...
DrRoboto's user avatar
  • 181
3 votes

Quadcopter frame design

To answer your questions directly, the X-shape is not the only design that will work. There are many variations of frame design around a number of rotors that can range from 3 to (in some cases) 8. ...
Ian's user avatar
  • 11k
3 votes

Design in the robotics world

Robots are often made multi-purpose. They're usually not redesigned for every other application, that'd cost quite a lot. A company that would like to use a robot, (let's say a packaging company) ...
Paul's user avatar
  • 221
3 votes

Is this large bipedal robot real or realizable?

On the video is a 4 meter tall mecha robot which makes heavy noise while walking forward. To determine if this is a real robot or fake, the first step is to enter the name of creator Vitaly Bulgarov ...
Manuel Rodriguez's user avatar
3 votes

Is it better to use software or hardware for object sorting?

You would have to do both. It's very very challenging to move an object without using hardware, and it's incredibly hard to see the colour of a brick with hardware. You'd have to break it down into ...
Josh's user avatar
  • 141
3 votes

What should be the ideal ratio for link lengths ( L1/ L2) of a 2 link manipuator robot with revolute joints?

This is a good question, and one you should definitely consider when designing a new robot arm. But unfortunately, it depends a lot on the configuration of your arm (i.e. how the joints will be bent),...
Ben's user avatar
  • 5,780
3 votes
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Recommended building materials for building a robot WITHOUT 3D printer?

With consideration cheap, strong enough, not ugly and easy to shape, then my recommendation is you can use clipboard. I have seen people win international robotic competition with robot made using ...
Albert H M's user avatar
3 votes
Accepted

How to perform decoupling between decision making and action execution in ROS2?

As a general rule of thumb, publications and topics are good for streaming data and commands where they're flowing continuously. Services are better for handling singular events that are not repeating ...
Tully's user avatar
  • 1,792
3 votes
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Why aren't more bipedal (or even quadruped) robots made with joints/articulations similar with those found on atmospheric deep dive suits?

Why aren't they, you ask? Typically, it would be a worse design. Atmospheric deep dive suits, and, for that matter, space suits, are designed to maintain constant internal volume. Otherwise the ...
r-bryan's user avatar
  • 1,261
3 votes

What are the pros and cons of Zip Chain Actuators in robotics?

The primary feature of a zip chain actuator is that it does not need extra depth to retract into. A standard linear actuator has a slider that will travel back behind the point of actuation. It will ...
Tully's user avatar
  • 1,792
2 votes

Choosing the right dimensions for an underwater glider

This is a classic design problem. It starts with want you want something to do - a design specification. Hence there is no one right answer. I have designed a number of both aerial and underwater ...
Paul Nealis's user avatar
2 votes

Stewart platform as robotic wrist joint

Bear in mind a Stewart platform has six degrees of freedom - yes it does reproduce the main motions of the human wrist, but it adds extra ones such as the ability to change its overall length. There ...
Andy's user avatar
  • 1,031
2 votes
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Artificial Intelligence Software Packages: Professionals, University education is oft' a step behind. What's actually being used?

I am not sure which end of the AI work you intended, so this may not apply. If you are working disconnected from hardware one might be better off with straight MATLAB / Octave. If you are planning to ...
daemondave's user avatar
2 votes
Accepted

Air hockey with a robot as an opponent

A well lit, perfectly circular object on a contrasting background, like a puck on an air hockey table, is pretty much the ideal use for webcam object tracking. A classic air hockey table has a light ...
Chuck's user avatar
  • 15.9k
2 votes

Mechanical design for base of robotic arm

We built a robot arm similar to the model in the following link. http://www.3ders.org/articles/20131113-make-your-own-3d-printed-trainable-robotic-arm.html We used 3D-printer to print all the links ...
Qizong Wu's user avatar
2 votes

idea for web application in robotics

There are the awesome "ROS Robot Web Tools" http://robotwebtools.org/ that give your ROS enabled robot a web interface. We use it as high-level interface for many of our service robots, as we can then ...
Squelsh's user avatar
  • 134
2 votes

Dynamic simulation of compliant elements in quadruped robot

Matlab Simulink has a blockset called Simmechanics. It is very well suited for robotic simulation (it is ment for multibody mechanics simulations). It is a bit tricky to set it up for mobile robots (...
50k4's user avatar
  • 6,632
2 votes
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3 way check valve

Two comments: One, you don't need a double/dual check valve; one on the inlet line and one on the outlet would work. See the image below. You haven't explained why two distinct check valves are less ...
Chuck's user avatar
  • 15.9k
2 votes
Accepted

Choosing the right Mecanum wheel

The problem appears to be that your drive motors are providing too much torque. In other words, there isn't enough friction between the wheels and the floor to counteract the force that the motors ...
Ian's user avatar
  • 11k

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