# Questions tagged [mobile-robot]

A robot which is capable of moving from one place to another, usually of its own volition.

486 questions
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### provide world map for ekf global localization problem

I am trying to implement the ekf_localization algorithm in page 217 (Table 7.3) of the probabilistic robotics book by Thrun. From my previous post, I understand that I need to extract observed ...
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### EKF localization data association

I am working with ROS indigo and clearpath huskyA200 and wanted to implement the EKF localization with unknown correspondences with my own hokuyo lidar data for a school project. Giving the algorithm ...
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### Relation between GraphSLAM and Iterative closest Point algorithm

I have lots of doubts about GraphSLAM, The GraphSLAM Algorithm with Applications to Large-Scale Mapping of Urban Structures. When I practically implement it I get matrix singularity error. I taken ...
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### GraphSLAM equation doubt

I have question about GraphSLAM implementation. To find out the path and map using GraphSLAM we rely on this equation: $$\mu=\Omega^{-1}\xi$$ where $\Omega$ is our information matrix which ...
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### Graph Slam Landmark remove and then again add it

I try to implement Graph Slam in real dataset. My data set have some data that describe that the Robot observe same landmark over and over with a large amount of time difference. Prof. Sebastian ...
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### How to detect loop in robot movement observing odometer data

I have some odometer data. This data are based upon robot movement. I can transfer those raw data to a motion equation from where I get x,y,and theta co-ordinate of a Robot. If I plot those x,y ...
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### How exactly does sensor fusion work in Kalman filters?

I've been looking into implementations of Extended Kalman filters over the past few days and I'm struggling with the concept of "sensor fusion". Take the fusion of a GPS/IMU combination for example, ...
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### Alternative to ROS? [closed]

This might be a tricky question, but having dug in deep with ROS I am noticing the complexity that one has to deal with. Simple Arduino programming is much simpler but of course can’t do many useful ...
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### How to avoid matrix singularity in GraphSLAM

I am trying to implement GraphSLAM from Sebastian Thrun's paper, The GraphSLAM Algorithm with Applications to Large-Scale Mapping of Urban Structures. When I compute the inverse of my information ...
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### How to generate Particle in Particle Filter

I try to implement FastSlam 1.0. To implement this I need to create particles. Now my confusion is that How to create Particles?I have some odometry and Measurement data. Using those data values how ...
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### How to apply Kalman filter in this case?

I have some straight and curve pieces with numbers, they are used to build tracks (of $5$ lanes) for my cars (figure $1$), I can send commands to the cars using an SDK on the Raspberry (set the speed ...
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### Graph slam augmentation of Identity Matrix

I am trying to implement GraphSlam. I go through this paper http://robots.stanford.edu/papers/thrun.graphslam.pdf. I have some doubt about the algorithm. I attached a picture with this question My ...
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### Matrix is singular error in GraphSLAM

I have gone through The GraphSLAM Algorithm with Applications to Large-Scale Mapping of Urban Structures. I implemented the code for GraphSLAM. The fundamental formula of GraphSLAM is \mu = \Omega^...
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### Pressure Sensors for Robot Bumper

I'm building an omni-directional robot base and want to add some kind of low-level obstacle detection. The complete robot will have LIDAR and camera for navigation but I'd like to add something at the ...
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### Transforming incremental pose from camera frame to wheeled robot base frame

I compute odometry using the stereo camera by minimizing reprojection error. I compute the incremental pose change between frames from time t-1 and t. The odometry is referenced to the left camera ...
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### Actual dimension of Omega in Graph Slam

I have a doubt about GraphSlam Algorithm introduce in this paper. I add a picture to express my doubts (from page 411, 9th in paper): As per my knowledge $\Omega$ is the information matrix. So in ...
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### GraphSLAM data accumulation problem

I try to implement GraphSLAM from this tutorial, The GraphSLAM Algorithm with Applications to Large-Scale Mapping of Urban Structures. I have some doubt while studying this paper. I hope people who ...
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### Position feedback of a continuous servo motor

How do I keep a track of the continuous servo arm's orientation with respect to the starting/center position? Would using a rotary encoder(relative/absolute) help? I do not need to hold on to a ...
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### GraphSlam Matrix Subtraction doubt

I am trying to implement GraphSlam from this paper. I have some doubt regarding the algorithm described in this paper at table2: Algorithm GraphSLAM_linearize. I have a doubt in line 7. As per my ...
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### GraphSlam doubt about variable elimination technique

I am trying to implement Graph Slam. For tutorial purpose I read the paper "The GraphSlam Algorithm with Application to Large-Scale Mapping of Urban Structures" by Sebastian Thrun. At the beginning of ...
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### Robotics RC Car hack help

I need help with a robotisation project, please. I am new to robotics and have the Maverick RC car pictured below: My project is to add Arduino and Raspberry Pi boards to control the speed and ...
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### Can a tablet be slaved to a laptop to act as a wireless usb?

I have built an InMoov Robot. The tablet I got for his controller is too slow. I am currently using a laptop to control him across a usb cable. I want to get rid of the usb cable. I was thinking of ...
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### ROS: joint_state_publisher dies when used in remote launch file

I've been trying to run robot_state_publisher and joint_state_publisher on a remote TX1 running Ubuntu 16.04 and ROS Kinetic. When running the node from a local launch file (manually ssh into the ...
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### How can I get the distance from a robot to a beacon?

I'm planning to create a Raspberry Pi robot to map a room. I intend to use a particle filtering algorithm as one of the central points of the project, that will allow me to work out my position ...
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### How can we perform Image based Visual Servoing when we dont have the depth information

I am trying to perform image based visual servoing for my robot using a monocular camera. The issue is that in order to calculate image jacobian I need depth information Z. Can anyone point me to ...
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### Question about dynamic window approach (integration)

I would like to use the dynamic window approach for collision avoidance. I have red the paper The Dynamic Window Approach to Collision Avoidance from Fox Burgard and Thrun (https://www.ri.cmu.edu/...
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### Confusion of EKF equations

I read Probabilistic Robotics by Sebastian THRUN (online version). I also read http://ais.informatik.uni-freiburg.de/teaching/ws12/mapping/pdf/slam04-ekf-slam.pdf Question1 : What will be the ...
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### Map merging of mobile Robots

I have Five Robots data.Which I used to generate maps. More preciesly Robot 1 generate Map1. Robot 2 generate Map 2, Robot 3 generate Map3, Robot4 generate Map 4 , Robot 5 geberate Map 5. Now these ...
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### Kalman filter and ekf main difference in elaborate way

I am studying about various filtering techniques for Robot pose esitimation. I came to know two very well known filter technique Kalman Filter and Extended Kalman Filter. To know about this two ...
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### Is a small time locally controllable system holonomic?

If you define a wheel that can only rotate and move in the direction it is pointing to but using a combination of motions (arbitrarily short) it can be moved sideways, does the system still remain ...
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### EKF based Slam implementation with landmark identification in Global frame

I am working on mobile Robotics. I want to implement Slam. I have a very specific question about EKF Slam. To implement Slam I read the book "Probabilistic Robotics". I read its online version. There ...
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### Sigma calculation for EKF based Slam

I am working on EKF based slam. I go through Probabilistic Robotics. I attachd a picture here. I have doubt about how to calculate Sigma. I am happy if someone share their views about Sigma. How to ...
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### What is the difference between a holonomic and an omnidirectional robot?

I have seen the usage of the term "omnidirectional" in robotics, but I have not found a (precise) definition. In the chapter Omni-Directional Robots from the book "Embedded Robotics", it is stated: ...
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### Bluetooth Controls instead of R/C Controls for simple Holonomic robot

I am new here and with little experience in robotics. I have assembled this holonomic robot: https://shop.wickeddevice.com/product/omniwheel-robot-complete-kit/ It has 3 Omni-wheels, 3 gearhead ...
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### Why use GraphSLAM?

I am doing some project on Slam. I have a data set of a moving Robot which can give me the value of forward velocity(m/s) and angular velocity(rad/s) and time(s). Now if this data are provided I can ...
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### Find out Robot Coordinate using odometer data

I have a data set name Robot_odometery which consist of 3 field namely, Time(s),Forward velocity(m/s) and angular velocity(rad/s). I taken this dataset from http://asrl.utias.utoronto.ca/datasets/...
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### What knowledge should I have if I want to establish a robotics company? [closed]

I know, robotics may refer to many things and it's extremely large field today. But if I can narrow the topic to something like Aldebaran(the company makes Nao robots), what knowledge should I have as ...
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### Plot Robot Position Ackerman Steering

EDIT: Solved by Petch who noticed my axes were not to scale. I am trying to plot the (x,y) position of a robot using ackerman steering in Matlab. Imput data: CenterDist: Distance traveled by robot ...
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### Methods for state estimation and real-time path planning of a mobile robot

I'm looking to start a project that incorporates some form of state estimation and path planning for a simple simulated robot dynamic model, in an environment that contains obstacles. I'm hoping to ...
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### Which is a good and cheap 3D LIDAR or other options?

Our team is planning to go for European Rover Challenge (ERC) 2018 for which we are designing an Autonomous rover. In order to implement SLAM, we need a way of mapping (with a range of atleast 2-4 ...
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### how to increase traction for small robotic acrylic wheels?

I am building a small robot weighing 2 pounds for a project. The robot will be working on a variety of surfaces, namely carpet and flat tile floors. I am planning to create 3 inch diameter acrylic ...
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### Obstacle Avoidance: Detection of goal inside the obstacle

It is easy to understand how a robot can avoid obstacle if the goal point is not within the obstacle (Point A) as shown in the figure. But I'm curious how could a robot know that the the goal point is ...
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### Inter-robot Collision Avoidance

I try to understand some MATLAB code (see below) i found from the web for inter-robot collision avoidance. But I'm not really understand, how the theory behind this code work. Can anyone help me ...
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### ROS: TurtleBot3 motors runs 60 seconds after message is seen in topic /cmd_vel

I am running ROS Kinetic, on a Turtlebot3 Burger with a Raspberry Pi3. The goal here is to remotely control the Turtlebot from another Raspberry Pi. The remote controller Pi sends movement ...
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### Easy cm accurate GNSS / GPS for rover with base station? [closed]

I am trying to design a system to measure snow depth during snow production on a tiny ski resort in Denmark. My idea is simple: Drive a rover over the ground during the summer, and obtain height ...
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### How to convert/transform robot local frame to global frame to use in Kalman Filter?

I'm currently working on the iRobot Create 2 platform using a RaspberryPi (Python) and ROS. I have an indoor navigation/ GPS system, which can provide me with x,y coordinates within its coordinate ...
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### Turtlebot 2 dimensions

I am trying to drive the differential drive kinematics of Turtlebot 2. However, I couldn't find the distance between 2 wheels on the datasheet. I'd appreciate if anyone could provide me this dimension....
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### Graph Slam Path and Map

Any one have any idea about Graph Slam. To implement graph slam you have to write down a equation mu=(inverse)omega*Xi; The result is the path and map. Now which one is path? Is mu represent the Path?