adabot

This is a stack for the adabot robot. Below are instructions for setting up the adabot workspace; they assume that you have correctly setup your development environment. Visit the adabot wiki for more detailed instructions.

mkdir -p ~/.ros_repos/
cd ~/.ros_repos/
hub clone anthony-jclark/adabot.git
hub fork
mkdir -p ~/ros_workspaces/adabot_ws/src/
ln -s ~/.ros_repos/adabot ~/ros_workspaces/adabot_ws/src/
cd ~/ros_workspaces/adabot_ws/
catkin init
catkin config --profile debug -x _debug --cmake-args -DCMAKE_BUILD_TYPE=Debug
catkin config --profile release -x _release --cmake-args -DCMAKE_BUILD_TYPE=Release
catkin profile set debug
catkin build

TODO

• add packages for physical device

• add script for the simple startup

• change name of components

  • weg --> ? (leg, extender, ...)

• fix CI to use custom docker file

• figure out why "<--" doesn't work in xacro files (in comments)

• consider making adabot a macro so that more than one can be imported

• -z argument for urdf_spawner in the gazebo launch file

• checkout Gazebo's skid steer plugin

• generate the control yaml file depending on the number of wegs per wheel

• wegs

  • tune PID values
  • tune effort values
  • velocity values

• wheels

  • add option to display wheel as cylinder instead of sphere

• all links

  • select friction model
  • adjust inertia tensor independent of mass (for jitter)
  • mu1, mu2, fdir1, kp, kd

• all joints

  • adjust limits, velocity, and effort
  • stopCfm, stopErp, implicitSpringDamper, cfmDamping, fudgeFactor

• run script from launch file to create control yaml and control launch files

• collision vs inertia vs visual geometries

• inertia macros for different primitives

• dynamic reconfigure to tune PID

• jitter due to high joint forces for low masses

• look at wheel control

• get joint outputs

• starting with a simple process of detecting slippage

• frequencies of sensor and actuator nodes

• node params (n.getParam)

• average /adabot/odom/filtered/twist/twist/linear/x

rqt_plot /adabot/odom/filtered/twist/twist/linear/x /adabot/odometry/twist/twist/linear/x

show how to manually tweak PID values

normalize number of spaces in launch files, etc.

find a better way to implement variable numbers of motors (for wegs)

apt-file search "" search installed packages for owner of a file apt-cache search "" grep on package descriptions dpkg -S "" similar to apt-file but works with ROS (without contents file) apt-cache policy "" display installed version and available versions

rostopic hz and bw to test publish rate and bandwidth

controller tuning:

• simulation time step and iterations
• isolate the issue (pid gains, damping, friction)
• low D
• look for high mass differences between connected links
• https://en.wikipedia.org/wiki/Ziegler%E2%80%93Nichols_method
• http://saba.kntu.ac.ir/eecd/pcl/download/PIDtutorial.pdf

http://wiki.ros.org/UnitTesting http://gazebosim.org/tutorials?tut=contrib_code&cat=development#WriteTests

reset:

• can't call rosservice call /gazebo/reset_simulation
  • this call causes all ROS nodes to stop updating for some time??
• call rosservice call /gazebo/reset_world
• call

rosservice call /set_pose "pose:
    header:
        seq: 0
        stamp: now
        frame_id: odom
    pose:
        pose:
            position: {x: 0.0, y: 0.0, z: 0.0}
            orientation: {x: 0.0, y: 0.0, z: 0.0, w: 1.0}
        covariance: [0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]"

• call similar service on other nodes (create services for my nodes)
• set weg extensions to 0
• set wheel speed to 0

weg extension based on all wheels check for bad simulation (timeout)

teleop

find a better way to implement variable numbers of motors (for wegs)

• add undriven differential wheels for odometry

• add channel to outside of wheels (for rubber bands)

• offset wegs so that they do not touch each other

• wrap config yaml and control spawner in group namespace