Questions tagged [control]
A method or device to manage, command or regulate some part of a system.
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Design: Single or Multiple Nodes For Robot Behaviors
I have built a docking node for my GoPiGo3 robot which offers /dock and /undock services. The docking node currently goes straight to the robot hardware for the docking/undocking commands which at ...
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Why is stepper motor closed loop vs open loop control such a drastic difference?
(Please move this to Electrical Engineering SE if appropriate)
Good day. I've been trying to build an inverted pendulum on a cart Linear Quadratic Regulator controller after teaching myself the math ...
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Impact of torsional compliance on motor control bandwidth
The stator of my motor is attached to a torsionally compliant body with limited rigidity, and rotor is connected to a gimbal frame. I need to know the impact of this compliance on the maximum ...
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Joy from smartphone via wifi
I'm a ros beginner student, sorry,
I would like to create a program to send its coordinates data to joy_node using a virtual controller that is moved by touch on a ...
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Gazebo dynamically modify parameters in plugin
I am looking for a way to dynamically change the variables that has been predefined in a robot model sdf file. In particular, I would like to tune the parameters of the velocity (lee) controller of ...
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is there a way to the ros1 combined_robot_hw in ros2?
Does ros2 have combined_robot_hw? I have two robot arms; how do I set them up so that the read/write for the two arms happens at the same time?
I have seen https://github.com/ros-controls/...
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Diff drive robot can not turn
I made a diff drive robot in the gazebo simulation, but it does not turn while moving forward. As seen in the video, although the right wheel rotates faster, the robot does not turn left. What could ...
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Is admittance control set by impedance control?
My goal is to use end effector as the ultrasound probe, so the sonographer can easily manipulate the end effector, allowing smooth motion of both translation and rotation.
Franka Emika robot provides ...
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sim2real gap in robotic arm trajectory execution
Lately, I've been working on projects where I have to replicate an existing robot trajectory in a simulator. I'd like to keep this question generic, but I guess that each software has its own answers. ...
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how to let ROS know my robot is front wheel diff drive?
the robot is ros controlled but the problem is that, it has wheels in front and caster at back, so when it turns around its axis, when near the wall it collides with the wall, we are using trajectory ...
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Gazebo robot falls over on spawn; "The published robot description file (urdf) seems not to be genuine"
In my gazebo simulation my robot fails to maintain itself. It falls over in the spawn and starts to vibrate by itself. There were multiple terminal errors. While fixing these errors, I sometimes cause ...
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PID Control on differential drive robot
I have tried to control the Pioneer robot in Webots simulator to follow the static target. This is the code I have developed. My main goal is to make a go-to single goal controller. The problem is ...
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Why is my model jumping around all over the place?
Every time it gets to that position it goes crazy, I'm not sure why. It's weird that the box is bobbing up and down as well. It's just supposed to be a simple pendulum / slider mechanism. URDF ...
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What would be a good objective function to tune a PID controller in a 6 DOF robot manipulator?
As stated above, I am currently trying to tune the PID in a controller for a robot arm (the input of the plant is torque, and the output is its state).
I first practiced with a single joint (1 DOF, a ...
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How should I optimize a PID in Webots correctly?
As stated above, I need to optimize the PID gains (the feedback) in the torque controller for trajectory tracking I am currently doing.
This is what I have done until now:
Begin simple, with just one ...
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What's the difference between the different types of "control"
I've embarked myself into an "action in robotics" journey, and I'm currently having troubles to understand the main differences between the different types of "controls" listed ...
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Lateral control for autonomous vehicles ( steering angle problem)
I am working on a control system for autonomous vehicles, i am using a kinematic bicycle model simulated on matlab simulink and the formula i used for the steering angle is given in the figures below ...
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What is this plate/wheel/disc called?
So this plate would attach to a motor and an arm would be attached to any one of the holes. As the motor rotates the plate it causes the arm to move in a reciprocating fashion. In this example, ...
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Problem with simulating correctly my robot when using EffortJointInterface
Hello everyone i'm simulating a differential drive robot on gazebo 11.0 (i'm using ROS noetic), and i'm trying to control each wheel separately using velocity control and using an EffortJointInterface,...
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Which NAV2 controller for following a given path with a certain speed?
I need to follow a given global path with a certain speed. For now, my plan would have been to use the MPPI controller in NAV2 with a custom critic for speed.
Is this a good approach? Are there other ...
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Issues with Torque Distribution in State-dependent Differential Riccati Equation (SDRE) Controller for 4W SSMR Trajectory Tracking
I am currently working on implementing a State-dependent Differential Riccati Equation Controller (SDRE) to track the trajectory of a 4-wheel skid steer mobile robot (SSMR), where torque serves as the ...
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Can we apply LQR control in high dimension - like to a full robot?
I have been watching Russ Tedrake's videos on robotics, which are wonderful. But I am confused by one thing.
So he talks about the application of LQR control and its ability to efficiently stabilize ...
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reset robot position using "/gazebo_msgs/srv/SetModelState" [duplicate]
I am trying to reset model position at a specific condition in ros2 humble. I found "/gazebo_msgs/srv/SetModelState" would be helpful in resetting position but it is not available when I run ...
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Implementing a simple MPC
I am trying to teach myself how an MPC works by implementing one from scratch.
I found a great resource that explains how an MPC works: https://cse.sc.edu/~gatzke/cache/npc-Chapter5-scan.pdf
There are ...
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Help with robot bimanual manipulator impedance controller
I have question with how should I focus the development of a impedance controller for two robots. I already built a controller for one arm but after a thorough search if literature or examples I didn'...
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Is it acceptable to convert the optimized control input state (acceleration) from my Model Predictive Controller to position
Good day,
I hope you are well. I currently have an MPC position controller that optimizes a set of control input accelerations given a trajectory.
u = [Ux_dot_dot Uy_dot_dot, Uz_dot_odt]
However what ...
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Mobile Manipulator: Is it possible to use the output state of an MPC position controller instead of the optimized control inputs (acceleration)?
Good day, I hope you are all well :) It's been 7 years since I've last been here haha.
I am currently trying to implement this paper: https://www.mdpi.com/2077-0472/12/3/381
Their mobile manipulator ...
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Rigorous terminology clarification - Path Planning, Path Following, Trajectory Planning, Trajectory Following and Motion Planning
I am asking this after having gone through quite a bit of literature and hope that it's not a repeat question.
I would like to know proper mathematical notion that clearly defines a Path and a ...
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I don't know how to get gazebo updated information
/cmd_vel Sends the speed value as a message to drff_drive.
/diff_drive sends the following ...
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Link num type variable with aio Staubli
I want to link a num variable with a aio input variable I receive from ECAT.
I am trying to do it in that way, but it does not work. Anyone who know how to do it in SRS?
I have defined Vel_cmd and ...
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Custom hardware interface type
I would like to write a controller that needs all joint states to update a single joint.
My idea was to create a class MyStateInterface which inherits from ...
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Integrating Alternative Local Planners (Controller) with ROS 2 Navigation2 Stack for an Ackermann Robot
I'm working on a project with ROS 2 Iron and the Navigation2 stack, focusing on an Ackermann-steered robot. I've encountered issues while trying to integrate alternative local planners, such as TEB, ...
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How to use MoveGroupInterface within a node?
I am a ROS beginner trying to write an interface for a robot arm in c++ that uses moveit2 for inverse kinematics. What I want to do is have a node with a MoveGroupInterface handle that I can use to ...
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ROS2 - Humble - ros2_control Possible to use position and velocity forward controller at same time?
Is it possible to spawn and use both a forward position controller and a forward velocity controller at the same time? My hardware interface supports torque, speed, and position (feedforward PID ...
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Lateral control for autonomous vehicles
I am working on autonomous vehicle control, i used the kinematic bicycle model,
For the speed reference I used a speed profile not a constant speed(given below [![speed][1]][1]
for the steering angle ...
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Real time velocity control with Moveit
I am working on a research project involving robotic welding, and once I get the motion plan with moveit, I want the end effector to move in specific velocity along the weld path, based on camera ...
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Navigation in Local Frame (odom frame)
I am working on a control related task - a docking procedure for an AMR to be specific. That task requires my robot's pose information throughout the planned path as it moves to the goal/docking ...
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Hinfinty Controller for TWO wheeled self balanicng robot
I'm trying to implement a H-infinity controller in a TWO-WHEELED-SELF-BALANCING-ROBOT, already implemented LQR for the same in gazebo, where the control input was torque(used this selfbalancing robot ...
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impliment car like steering in ros2_control
I want to implement a 4 wheel robot with car like steering(having 2 front steerable wheels and 2 back drive wheels) in ros2 using ros2_control. Can you suggest me which ros2 controller should I use(...
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Modelling thrust on quadcopter in simulink
I want to model aerodynamic forces such as thrust on all motors of quadcopter in simulink.But equations for thrust involves density of air , but then we have to include model air in simulink . So what ...
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About Husky UGV Connection
Somehow a Husky UGV came into the lab without any sensors or onboard PC.
Fortunately, there is a laptop with ROS2 Humble installed and a PS4 controller.
Q1. What do I need to do to act as an Onboard ...
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Why is admittance control better than impedance control for huma robot collaboration?
I have seen many papers that use admittance control for human robot collaboration but no one tells why admittance is the choice and not impedance. Is it something very trivial that I should know or ...
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Moveit_servo with ur_modern_driver
I have been working on a UR10 (older version, thus using ur_modern_driver) for pick and place movements.
However for a specific case I want to change to smooth servoing towards an object based on ...
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Mambo parrot /tello control propeller speeds
From my understanding, for parrot mambo and tello drones, we control forward-backward, up-dow, left-right, and yaw speeds (in m/s and deg/s). But the low level control is control the 4 propeller ...
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Creating a Custom Hardware Interface for a Two-Wheeled Mobile Robot for ros2_control?
I am in the process of developing a custom two-wheeled mobile robot with differential control, and I want to integrate it with the ROS 2 ecosystem, specifically leveraging ros2_control. I understand ...
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End effector velocity control of a 6-DOF robotic manipulator using MPC
I've been trying to utilize Model Predictive Control (MPC) scheme that I have for end-effector position reference $x(t)$ tracking control to build end-effector velocity reference $\dot{x}(t)$ tracking....
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How do I send a new position to my 5 dof robot arm?
I am a newbie with ros2 control. I am using ros2 iron on Ubunto 22.04 (Linux Mint). I made a copy of the ros2_control demo example #7.
This is the one that is launched with the command ...
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What are the gain and bias parameters used to control actuators?
When I read the Mujoco official document, the following paragraph raises my confusion:
Different settings of the gain and bias parameters can be used to
model direct force control as well as position ...
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Controlling motion of single link
This seems like it should have been a well studied problem, but I can't find any solution.
We want to define what a motor must be commanded to do to move a single link with mass $m$ and length $l$ $...
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Best practice for logging callback durations and execution times in ROS
I'm wondering if there are any best practices for logging callback durations and execution times in ROS? As my system evolves and implementation is changed, I'd like to be able to monitor the ...
