Relaxed IK ROS1 for Kinova Gen3 Robotic Arm

Introduction

This repository is based on the RelaxedIK repository, with additional config files to use relaxedIK with Kinova Gen3 Robotic Arm.

NOTE: the required Kinova config files needed to implement RelacedIK have already been generated and are provided to you in this repository. If you want to generate them yourself, you will need to clone this repo and follow the guide there.

Dependencies

Make sure you install the following dependencies:

Python Dependencies

readchar:

sudo pip install readchar

fcl collision library: https://github.com/BerkeleyAutomation/python-fcl

sudo pip install python-fcl

scipy:

sudo pip install scipy

Pyyaml:

sudo pip install PyYaml

kdl urdf parser:

sudo apt-get install ros-[your ros distro]-urdfdom-py
sudo apt-get install ros-[your ros distro]-kdl-parser-py
sudo apt-get install ros-[your ros distro]-kdl-conversions

Pypcd: https://github.com/dimatura/pypcd Lastly, update your version of numpy:

sudo pip install --upgrade numpy

Rust Dependencies

To use this wrapper, you will first need to install Rust. Please go to https://www.rust-lang.org/learn/get-started for more infomation.

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
source "$HOME/.cargo/env"

Downgrade to rust 1.58:

rustup install 1.58 
rustup default 1.58

Getting Started

1. Make sure that you have installed all the dependencies.

2. Create a new workspace and place the package ros_kortex in the scr directory.

3. Clone the kinova_positional_control repo to the src directory in your catkin workspace.

   git clone https://github.com/lagenuina/kinova_positional_control.git

4. Clone the pid repo to the src directory in your catkin workspace.

   git clone -b joint-controllers https://github.com/GOPHER-System-Intergration/kinova_pid.git

5. Clone the relaxed_ik_ros1 repo to the src directory in your catkin workspace.

   git clone https://github.com/lagenuina/relaxed_ik_ros1.git

6. Build your catkin workspace by using catkin_make in the workspace root directory.

7. Initialize relaxed_ik_core (the Rust library of Relaxed IK) as a submodule by running the following command from the project directory (/src/relaxed_ik_ros1):

   git submodule update --init

   1. If the previous command didn't return an error, you can skip this step. Else, you might need to Setup a SSH key for Git:

   Paste the text below, substituting in your GitHub email address.

   sh-keygen -t ed25519 -C "[email protected]" 
   eval "$(ssh-agent -s)"
   ssh-add ~/.ssh/id_ed25519

   Copy the SSH key to your clipboard.

   clip < ~/.ssh/id_ed25519.pub

   Login to your GitHub account > Settings.

   In the "Access" section of the sidebar, click SSH and GPG keys.

   Click New SSH key or Add SSH key.

   Create a Title and paste the SSH Key under "Key", then click Add SSH key.

8. After the submodule has been initialized successfully, navigate to the relaxed_ik_core folder and compile the core:

   cargo build

9. Look at <settings.yaml> in the folder relaxed_ik_core/config and follow the instructions there to customize the parameters, and personalize the environment obstacles. Note that you don't need to recompile relaxed_ik_core every time you change the parameters in <settings.yaml>.

10. Look at <kortex_info.yaml> in the folder relaxed_ik_ros1/relaxed_ik_core/config/info_files and edit the starting configuration of the robot.

Let's test!

1. Launch Kortex driver:

   roslaunch kortex_driver kortex_driver.launch

2. Launch the Relaxed IK solver and PID by typing the following command:

   roslaunch relaxed_ik_ros1 relaxed_ik.launch

   If the previous command gave you an error, make the script pid_joints_relative.py executable with chmod +x.

3. Launch PID controller:

   roslaunch pid arm_controller.launch

4. Now that relaxedIK is ready, you can control the robot with the keyboard! To do so, initialize the keyboard IK goal driver in a new terminal with the following command:

   rosrun kinova_positional_control keyboard_ikgoal_driver.py

   To use the keyboard controller, please ensure that the termainal window where <keyboard_ikgoal_driver.py> was run from has focus (i.e., make sure it's clicked), then use the following keystrokes:

   c - kill the controller controller script
   w - move chain 1 along +X
   x - move chain 1 along -X
   a - move chain 1 along +Y
   d - move chain 1 along -Y
   q - move chain 1 along +Z
   z - move chain 1 along -Z
   1 - rotate chain 1 around +X
   2 - rotate chain 1 around -X
   3 - rotate chain 1 around +Y
   4 - rotate chain 1 around -Y
   5 - rotate chain 1 around +Z
   6 rotate chain 1 around -Z
   
   i - move chain 2 along +X
   m - move chain 2 along -X
   j - move chain 2 along +Y
   l - move chain 2 along -Y
   u - move chain 2 along +Z
   n - move chain 2 along -Z
   = - rotate chain 2 around +X
   - - rotate chain 2 around -X
   0 - rotate chain 2 around +Y
   9 - rotate chain 2 around -Y
   8 - rotate chain 2 around +Z
   7 - rotate chain 2 around -Z

Possible Errors

One of the possible errors you might encounter is when running the last command rosrun relaxed_ik_ros1 keyboard_ikgoal_driver.py for testing purposes:

thread '' panicked at 'assertion failed: min_bound == min_bound", /home Valfakentavr/.cargo/registry/src/github.com-1ecc6299db9ec823/ncollide3d-0.21.0/s rc/query/algorithms/gjk.rs: 124:9 note: run with RUST_BACKTRACE=1' environment variable to display a backtrace

To solve this error, go to RVIZ and change the fixed frame from common_world to base_link. Then Save Config As relaxed_ik_viewer.rviz with replacement.