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How can I apply different control approach without having a state space model?

Many control strategegies (PID is not neceserily one of these) are computing some of their parameters from your system. If you do not want to model your system yourself (or play around with it until ...
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6 votes

About official robotics system toolbox Matlab and Peter Corke Robotics toolbox matlab

There are very few problems having both toolboxes installed. The biggest gotcha is the function angdiff() which is provided by both toolboxes but defined differently. If you want to stick with ...
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5 votes

Mathematical modelling of system dynamic on matlab

the Simulink diagram is straightforward. It is a matter of connecting blocks. For the differential equations provided in your post, the simulink is For $u_1$ and $u_2$, I've chosen the unit step. ...
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5 votes
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Meaning of a negative step response with quaternion

Welcome to Robotics, PaoloH! This is a fantastic question for Robotics - It has some Matlab/Simulink, some control theory, some spatial (quaternion) representations, etc. Robotics is the place to come ...
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4 votes

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 ...
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4 votes

Human arm inverse kinematics

You are tackling two non trivial problem at the same time 1. Inverse kinematics of an overactuated manipulator 2. Obstacle avoidance using the null space By definition of the null-space projection ...
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4 votes
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how to implement and code inner and outer PD controllers for quadrotor for position tracking

As extension to this answer, I'd like to share with the community a Simulink model implementing the system described above. It does not represent a solution for the code reported by CroCo but it may ...
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4 votes

Why I'm getting very long terms in the inertia matrix (or dynamics model) of the robot using matlab script?

You can use the 'simplify' command , e.g : a=simplify(A*B) .This command is calculating some trigonometric functions thus making your expression shorter .
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4 votes
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Using Gazebo installed on same machine in MATLAB

The MATLAB tutorial doesnt cover this aspect well about when you have matlab and gazebo running on the same linux machine with no virtual box. Change your linux ethernet interface ip address ...
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4 votes
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Complimentary filter issues

There are quite a few things wrong here. I'll split them into two sections: technical errors, and coding warnings. Technical Errors: You are not calculating your angles from accelerometer readings ...
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4 votes

Does simulink accepts robotics toolbox in matlab?

The MATLAB function block in Simulink has some limitations. The fact that Link.m is referred to as a function not a class is a worry. I recreated your Simulink model and get similar error messages, ...
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4 votes

Matlab Inverse Kinematics 6 DOF

Ideal solution can be defined in many ways. The simplest way to choose one is to compare which of the 8 solutions is closest to your current pose in joint space. This is usually a good idea if you ...
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4 votes

Can I write the seperation principle for LQG controllers in this state space form?

Both state space representations are equivalent. For example the eigenvalues of the two closed-loop system matrices should be the same. However when implementing LQG you only have access to the ...
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4 votes
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Determine the relative camera pose given two RGB camera frames in openCV-python

If you understand how relative pose estimation works in theory, it should be quite trivial to translate it into OpenCV code. First, you can pick any feature detection/description approach you like (...
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4 votes

How to take prediction step in particle filter?

The prediction step generates a new set of states from the old set of states. The motion model of the system is used to make this best estimate of what we think the new state might be. The motion ...
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4 votes

Is the translational vector (positon) in transformation matrices in cm or another unit (MATLAB)?

They are in whatever units the kinematic analysis uses. It could be feet, inches, meters, millimeters, or whatever. Your question is a bit like asking “what unit is the Pythagorean theorem written ...
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3 votes

RGB-D SLAM - Compute Information Matrix

The information matrix is the inverse of the covariance matrix. In this case, the covariance is over the variables (x,y,z,qx,qy,qz). It is assumed that your quaternion is normalized to be unit ...
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3 votes
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MATLAB 3D Simulation with SOLIDWORKS model

I use CAD software to generate 3D models, convert those 3D models to an STL format, then load those STL files to Matlab with the following script: ...
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3 votes

Why I'm getting very long terms in the inertia matrix (or dynamics model) of the robot using matlab script?

It really doesn't sound very unexpected for your equations to become this long. Something that might help a little, is using assumptions for defining symbolic variables. ...
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3 votes
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Are there any aerodynamics modeling/simulation software that is capable to consume a SolidWorks model and to interface with MATLAB/Simulink?

Matlab has a package called Simscape that you can use for modeling physical systems in general. I would just caution you up front that Simscape is almost more like a plugin manager in that it enables ...
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3 votes
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Mobile robot algorithm implementation error

So I'll point out what might be some problems, at-a-glance, but wow this is one of the longest questions I've seen here. I'm pretty swamped with real-life stuff at the moment, so I'll just point these ...
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3 votes
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How to move root locus to the left?

Brief process for pole placement in Matlab: Check that the system is actually controllable. . ...
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3 votes

Does simulink accepts robotics toolbox in matlab?

You appear to be using a third-party toolbox, the Robotics Toolbox. If it's not running in Simulink, then it might not run in Simulink. If you want something that does, try the official toolbox. ...
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3 votes
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Reading multiple signed digits from serial port

It looks like you're doing this in a very round-about manner. You said, The matlab function in sumlink is supposed to read the received ASCII characters and add them to a variable until it reaches ...
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3 votes
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How to get Max Torque on Robot arm 's Joints (RRR)

Torque is pretty easy to calculate for a single static arm configuration. Torque is just the length of the moment arm * the perpendicular force. And it is easy to decompose the problem into X and Y ...
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3 votes
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Can I write the seperation principle for LQG controllers in this state space form?

This is really a lot to look at, but the most glaring issue I noticed off the bat is your definition of the control signal $u(t)$. What is the input to your controller? What should be the input to ...
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3 votes
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Inconsistent results between Simulink derivative model and tf for PD controller

After some investigation, there is a problem with the derivative block in Simulink. tf yields the correct response in my case. While the values of Kd has been ...
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3 votes
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Control system in Matlab with RSA encryption

:EDIT: Your numbers must be integers POSITIVE INTEGERS. (link) This is probably the root of the trouble you're having. Interesting that the paper didn't mention anything about this. I'm not sure how ...
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3 votes
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Roy Featherstone toolbox robot model

I changed the code and now it works properly. ...
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3 votes

Solving pseudo inverse of Jacobian in Matlab/Octave

After running your code, it looks like everything is behaving how you have defined it to. The problem you are running into has more to do with the Jacobian itself and less to do with any mistakes you ...
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