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Building trac_ik_python for Windows 10 using MSVC2019

I’m trying to build TracIK-python with Microsoft Visual Studio 2019 for Windows 10 and am making use of the available trac_ik_wrap.i file in the swig folder to ...
14 views

HD Map Creation in Real Time [on hold]

I have a robot that I want to navigate through a complex environment. I want to make an accurate 360 degree surround view map of the robot's environment. How can I do this? I have 2 180 degree lidars ...
18 views

Best Sensors/Upgrades for mBots? [on hold]

So i have regular mBot with black/white line follower & ultrasonic sensor. What would be the best thing to upgrade it with? Also is there something that is similar to those blue metal rods? I ...
28 views

Complementary filter for gyroscope and accelerometer

I am trying to understand how the complementary filter works. I did some research and i found this: I am confused about the noise and drift before any filter is applied. I have 2 questions: In the ...
40 views

Fusing Multiple Lidars Into 1 Point Cloud

I have a car with 8 lidars, each with a field of view of 60 degrees. My car looks like this How can I merge all the lidar readings into 1 point cloud?
28 views

feedback linearization controller for a quadrotor

I am trying to develop a controller for a quadrotor using dynamic feedback linearization technique, but I am not sure I am doing thigs correctly. I know that for designing such controller I have to ...
5 views

What is the ~tf_prefix parameter does?

I have a TurtleBot3 Robot and when I’m trying to do this command to start the nodes (The ROBOT is real) roslaunch turtlebot3_bringup turtlebot3_robot.launch I’m ...
27 views

Old toy robot - anyone remember this? [on hold]

Apologies if this is not the right place, but.... Does anyone know what this toy robot might be? I was given it years ago when I first started robotics courses, now it has become a favourite with my ...
18 views

Any alternative to finding singularity of Puma 560 than differentiating the Jacobian and putting the Det=0?

Any alternative to finding singularity of Puma 560 than putting the Jacob Det=0? Also when it says the axes intersect, which axes do they mean? The z?
13 views

How to create an artificial muscle in Gazebo? [on hold]

I am looking for a function in Gazebo to shrink an object related to two other objects. The artificial muscle will have a mount on the rotating element to increase the available angles of rotation of ...
10 views

Velocity obstacle method in joint space

The velocity obstacle (V0) method and it's variants such as the reciprocal velocity obstacle and optimal reciprocal velocity obstacle method have been deployed for multi-agent reactive navigation. By ...
16 views

how to implement a wall following controller for a TurtleBot3? (ROS - python)

I want to implement a wall following controller for my TurtleBot3 (with ROS system). sensors which I have on the robot: lidar(360) and optional 2 ultrasonic sensors on the side (1 on left and the ...
5 views

Dynamixel MX - Open CM 9.04 + Open CM Exp - Issue With Bootloader

I am using Dynamixel MX 64 AR with Open CM 9.04 + Open CM Exp using Arduino IDE. I am using the following code to find Dynamixel ID and Baud Rate: ...
10 views

Trying to make a map with gmapping but Rviz shows nothing

I'm trying to visualize and create a map using a Lidar and Rviz. I have a Lidar that publishes the LaserScan data on /scan and that is visible in Rviz. That is working fine. I also have installed ...
24 views

Gazebo GUI doesn't show up

I tried Gazebo 9 and 10 on Ubuntu 18.04 MATE and it quits in a few seconds without showing Gazebo GUI. I'm running it on 32-bit Intel CPU with 950 Graphics chipset (pretty old). Here is what I see in ...
24 views

Why Drone flips over while taking off?

Noob here. Response is very much appreciated. I have built a drone based on apm 2.8. however, it doesn't lifting up and flip over when it start to fly. Can you please guide what could be the possible ...
The below rtk-gps measures position to about 1.5inches for $1500 and an update rate of 5Hz on gps, and it measures 12.6mm x 4.6mm so that it would easily fit inside of a 20mm-diameter tube-shaped ... 1answer 33 views Servo motor torque I am confused with the torque ratings of servo motors, or I guess it is general while choosing any motor. For example a servo's torque is rated as 10kg-cm, so does that mean it can handle a 100N ... 0answers 13 views VFH/VFH+ Axis Orientation & Sensor Angles I have been struggling with trying to get the VFH+ implementation working correctly using Orca-Robotics implementation which seems to be the same implementation used in the ROS package and MATLAB and ... 0answers 20 views RC controlled underwater robot [duplicate] I am working on a project to build a remotely controlled underwater robot to work in pure water tank. The max depth the robot has to dive is 40cm, and the robot has no over-the-water antenna. I ... 0answers 21 views Coupled joints limimit I have 6dof articular robot. All joints are revolute. The limit of 3rd joint depends on the position of 2nd joint. I need to write function which returns 0 if 3rd fits limits with respect to 2nd joint ... 0answers 13 views Dynamixel MX 64 AR Control with OpenCM Exp+ Open CM 9.04 - Arduino IDE [closed] I am using Dynamixel MX Series 64 AR Servos and using Open CM Exp+ Open CM 9.04 hardware. I am using Arduino IDE. Can anyone provide me a sample code to run the servos? 1answer 38 views RC transmitter/receiver for underwater robot [closed] I am working on a project to build a remotely controlled underwater robot. The max depth the robot has to dive is 40cm. I tested the 2.4GHz RC transmitter and receiver and it could work only up to ... 0answers 35 views Fusion multiple LaserScans to PointCloud I am currently trying to do 3D SLAM with two 2D Lidars and possibly additional IMU in ROS. However, there seems to be no ROS package available to meet my needs. The closest one would be laser_pipeline ... 1answer 32 views Moving clock arms individually I have as project to build something like this ( using arduino if possible ): http://clockclock.com The one modelization that came across my mind is to take 2 sticks ( as clock arms ) and command ... 0answers 25 views how to rotate a small metal part, precise (0.01 Deg) and repeatable? For rotating a (90 grams metal, 30mm*30mm*15mm) part in a system, I need a mechanism with these constraints: The part (and other attachments) can rotate with about 0.01 degree or less precision. In ... 0answers 24 views How can I break down this easily to find out the homogeneous transformation for 3 jointed robot? I am a beginner at this and, I am trying to find the best way understand how to do this. I have tried youtube but, to no avail. I appreciate any tips. 1answer 39 views Localize a Mobile Robot on a Mirror I am currently busy with a project which requires me to construct a robot capable of cleaning a heliostat (movable mirror used to redirect sunlight). Heliostats are basically large flat mirrors that ... 1answer 21 views Is there a table of DC motors in relation to weight/mass? I want to find the fastest for my build I am building a line follower robot for a science competition, i have the weight of the components but i don't know what would be the fastest motor i could use to reach the best avg speed of the robot.... 1answer 24 views Odometry heading and laser scan heading not point to same direction please help, after so much research still cant find a single solution from google. some say offset, but there is no offset in the configuration. problem: odom direction and laser scan heading didnt ... 1answer 25 views How to convert serial data to sensor_msgs/Range Message I have a ROS node which manipulates a serial frame, the frame contains ultrasonic measurements, I have to extract this measurement and publish it as ... 0answers 28 views Formation control for ground vehicles I am working on a project where I am aiming at connecting multiple vehicles in a formation and allowing hive control of the formation. The robots (husky-like) use ROS and so I was hoping to ... 1answer 31 views Having trouble getting correct homogeneous transformation matrices for my robotic arm I am working on a project to build and program a robotic arm. And, no, this is not a HW problem. I have watched a ton of tutorials on the HTM, but its still not fully clicking. The image shows my ... 2answers 42 views In path planning, what kind of path is feasible for a nonholonomic robot? For a car-like nonholonomic robot, What kind of path is feasible? Is it right that a path is feasible for a car-like robot if it's curvature continuous, and the curvature on any point doesn't exceed ... 0answers 31 views Mobile Antenna question I have a rocket-shaped (tube-shaped) mobile 20mm in diameter. From a base-unit, 600yards away, I want to be able to send two floats (call it x and y) every 1/60th of a second (60Hz data rate [or ... 1answer 30 views I want to activate a remote shock collar based on messages in a discord server So, for starters - this is a kink thing and not an animal abuse thing. I have an introductory understanding of electrical engineering (the most complex thing I've done is make an oscilloscope from an ... 1answer 26 views iRobot Create2 Programmable Robot: what is already in the robot I want to buy the programmable iRobot Create2 and I have some questions about: The "autonomous navigation" with obstacle avoidance is just implemented in the robot when I'll buy it? And what about ... 0answers 16 views How to install ROS melodic over Network proxy Maybe it is a repeated question, but really i have no solution i am trying to install ROS melodic on Ubuntu 18.04.3 LTS, using my Wifi the things went good, but at my office where i have a desktop ... 3answers 92 views How to control the velocity of a mobile robot? I have a differential drive robot whose linear velocity and angular velocity is to be controlled. The current strategy for doing that is: A high level path tracking module spits out the reference ... 3answers 25 views A powerful pull/rotate device that provides a certain (controllable) force? I don't know how to call the device I'm looking for (or need to create), maybe you can help me with terminology too so I can at least search.. I want something that either rotates or pulls with a ... 1answer 36 views Is it to possible to measure a room exact with rplidar? I want to measure a room using rp3+, rplidar, ROS and SLAM. It should be easy possible to create mapping of the room. But how exact it would be? Is it possible to get less than 1 cm precision over ... 0answers 19 views How do I know if a wheel and stepper motor fit together? Looking for some wheels and a stepper motor to make a self balancing robot. How do i know if the stepper motor shaft can fit in the wheels? I cant find the shaft diameter when looking at some ... 0answers 40 views Partial CoM, the velocity Jacobian and Control New to robotic arms here. I am currently working with a 6-DOF robotic arm shown below: I have derived the FWD Kinematics and mapped the joint angles and the resulting end-effector positions. When I ... 1answer 43 views Cannot get 3 DOF bicycle model to run correctly I'm trying to simulate a vehicle using a dynamic bicycle model but I cannot seem to get it working. If I set a constant steering angle the lateral velocity grows exponentially and creates impossible ... 1answer 54 views Is there a straightforward 16bit microcontroller? Background Some of my sketches or ideas require a common data buss to all perph chips. The issue This way issue still lays before me, how then, if I am going for a common data buss. how do I ... 1answer 51 views 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 ... 1answer 41 views Regarding kalman filter implementation I think I might have originally posted this in the wrong stack exchange forum, link. I think this might be the right place, I am not sure if posting again is considered "bad style", I apologize if ... 2answers 78 views /odom topics not matching ERROR I have an existing ROS workspace which was built in C++. I am trying to implement a node built by The Construct in python which reads distance travelled from the ... 0answers 14 views Two Link Manipulator End Effector Position My professor described the end effector position as$q_{e} = \begin{bmatrix} x_e \\y_e\end{bmatrix} = \begin{bmatrix} l_1 cos(\alpha_1) + l_2cos(\alpha_1 + \alpha_2) \\ l_1 sin(\alpha_1) + l_2sin(\...
I am reading the paper "Motion control of wheeled mobile robots" at page 5, as we have the equation (34.7), i wonder how it contains $− dc(s)\dot s$ in side. As the triangle law of vector: \$\vec{OP}=...