panda_qp_ws

A workspace to test panda_qp_control

Installation

We are assuming that ROS noetic is already installed on your computer. We first need to make sure a couple of stuff are installed

sudo apt update
sudo apt install python3-rosdep python3-catkin-tools build-essential cmake git libpoco-dev libeigen3-dev
pip install scipy

Then create the catkin workspace

INSTALLATION_PATH=~/panda_qp_ws
mkdir -p $INSTALLATION_PATH
cd $INSTALLATION_PATH
git clone --recurse-submodules git@gitlab.inria.fr:auctus-team/components/robots/panda/panda_qp_ws.git src
catkin config --init --extend /opt/ros/noetic
rosdep install --from-paths src --ignore-src -r -y
catkin build
source devel/setup.bash

Note: you can add the last line to your ~/.bashrc to avoid having to source it every time you open a new terminal.

Usage

In simulation

For a velocity controller : roslaunch panda_qp_control velocity_control.launch sim:=true

Note: The simulation of the robot in velocity is a bit hacky for now. It uses a EffortInterface. The joint velocity computed by the QP is fed to a proportionnal controller as k_p (\dot{q}^{opt} - \dot{q}). This is because for now the franka_gazebo doesn't take into consideration a VelocityJointInterface. Hopefully this will be fixed with https://github.com/frankaemika/franka_ros/pull/181

For a torque controller : roslaunch panda_qp_control torque_control.launch sim:=true

On the real robot

For a velocity controller : roslaunch velocity_qp velocity_control.launch robot_ip:=your_robot_ip

Note: There is the same error as with the simulation. Therefore the robot is not stiffly actuated. This can be fixed by using a hardware_interface::VelocityJointInterface but it prevents simulating the robot.

For a torque controller : roslaunch panda_qp_control torque_control.launch robot_ip:=your_robot_ip

Run a trajectory

In this version of panda_qp_control, trajectories are computed using MoveIt. Several examples of trajectories are available in the package moveit_trajectory_interface/test.

To launch a trajectory simply run the command : rosrun moveit_trajectory_interface go_to_cartesian_pose.py

MoveIt is used to allow a more high level definition of a trajectory than with panda_traj. MoveIt also include obstacle avoidance feature when planning for a motion. External sensors can also be added to sample the environment and take it into account durint the planning. The moveit_trajectory_interface is a package that grabs a trajectory object planned by moveit and exposes the resulting trajectory as a function of time. A new point along the trajectory must be fed to the QP controller at each time step (1ms). More information on the trajectory generation can be found here)

If one wants to use the old way to generate trajectories, a branch with kdl_trajectories is available here

Optional roslaunch parameter :

robot_ip IP adress of the panda robot

sim Run the code in simulation on Gazebo

load_gripper launch the panda model with its gripper

Controller parameters

The controller parameters are stored in a yaml file in the /config folder and loaded as ros parameters in the run.launch file.