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1500 questions
4
votes
3 answers
Is SLAM done only first time in a given environment
I am training Turtlebot 2 to move around the office. I come from robotics hardware background but relatively new to computer vision and robotic mapping.
Here are my two fundamental questions related to localization and mapping.
The algorithm we…
PagMax
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4
votes
2 answers
Jacobian of the observation model?
The state vector is
$$ \textbf{X} = \begin{bmatrix} x \\ y \\ v_{x} \\ v_{y} \end{bmatrix}$$
transition function is
$$
\textbf{X}_{k} = f(\textbf{X}_{k-1}, \Delta t) =
\begin{cases}
x_{k-1} + v_{xk} \Delta t \\
y_{k-1} + v_{yk} \Delta t
…
CroCo
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4
votes
2 answers
How to calculate heading more accurately using dead wheels?
I am trying to figure out a more accurate way to calculate the change in the heading of a robot. I have two small omni wheels on either side of the robot facing forward and one on the right side facing sideways.
Currently the heading is calculated…
Tomahawk2001913
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- 4
4
votes
1 answer
Battery weight in quadcopter
We all know that the fly time of a quadcopter is proportional to its weight (and the propellers size, etc), and a high capacity battery is heavy, but also a high capacity battery would make the fly time larger.
I need a chart or comparison between…
Unnamed
- 171
- 3
4
votes
1 answer
Make robot drive as far from obstacles as possible
I am trying to make robot drive around the room, avoiding obstacles with pathfinding. The problem is I get few waypoints from pathfinding algorithm for robot to drive to (green dots), but it drive a bit too close to corners. I try avoiding that by…
Name
- 41
- 1
4
votes
2 answers
Implementing ESKF
I'm currently struggling with implementing the Multiplicative Kalman Filter or Error State Kalman Filter as described by Landis Markley in Attitude Error Representations for Kalman Filtering. Sadly there is two versions of almost the same paper…
hobbeshunter
- 150
- 5
4
votes
2 answers
Inverted pendulum controller
I had an exam yesterday, and I was asked the following question:
Why PID controller is necessary for stabilizing the inverted pendulum on a cart, why not we just use PI or PD?
Now I've seen some papers taking about using PD to stabilize the inverted…
Tamim Boubou
- 43
- 2
4
votes
1 answer
IK - 3dof - iterative
I want to solve for a 3dof planar arm using gradient descent to approximate end position. Now I am a little confused about the formula and was wondering if someone can help me out.
This is my thought process:
First start about using the forward…
baconStrips
- 41
- 3
4
votes
1 answer
Performing Image alignment using pyramid levels with semi dense depth
To gain some confidence, I want to implement the camera tracking (optimization problem) discussed in Semi Dense Visual Odometry for a monocular cameraJ Engel, J Strum, D Cremers
$$E(\xi) =…
vyi
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4
votes
2 answers
Calculating Error of Arm Manipulator
How can we calculate the error position of arm manipulator?
Let's say we have a Transformation Matrix:
$$\begin{bmatrix}
R_{00} & R_{01} & R_{02} & x\\
R_{10} & R_{11} & R_{12} & y\\
R_{20} & R_{21} & R_{22} & z\\
0 & 0 & 0 &…
Michael Iskandar
- 43
- 3
4
votes
2 answers
Why is behavior-based robotics not as popular as deep learning or reinforcement learning?
I am a master student in Germany and one of our professors is doing robotics research but with a different paradigm - the behavior-based robotics based on Subsumption Architecture developed by prof. Rodney Brooks from MIT in 1986. I was looking…
Vrabii Daniel
- 43
- 2
4
votes
3 answers
Is a thrift store a good place to get a servo motor?
I'm trying to learn about a very basic motor, the servo motor. Can these be found a thrift stores like Goodwill in old toys? Are these "robotic" quality? What toys or other kinds of things would I scavenge? All I want to do is get a motor. …
johnny
- 141
- 2
4
votes
1 answer
Robotic arm chassis
I've been curious about how the plastic chassises of the robotic arms in robotic competitions are manufactured. For instance, the following arms clearly have 10-20 plastic parts each, if not more:
Injection moulding such large parts can easily…
Kar
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4
votes
3 answers
How can we manage stepper motor cables?
I need to actuate 3 or 4 Cnc-like Nema 23 (~1N.m torque) stepper motors, I would like some cable solution to connect easily the motor to the motor driver.
I have not yet bought anything, I have searched various robotic stores and ebay, but did not…
darkblue
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4
votes
1 answer
3-DOF Robot Dynamics error in Robotics Toolbox
I am trying to compute dynamics of 3 DOF robot using Robotics Toolbox by executing this code:
robot.accel(q, zeros(1,3), zeros(1,3))
But I am getting this error: Assignment has more non-singleton rhs dimensions than non-singleton subscripts
My…
Capri
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