Tycho Rover Code

This project contains the code needed to drive the Tycho prototype lunar rover. Currently, it is set up to drive a 1/10th-scale model using an XBox 360 controller.

There is also an OpenSCAD file that can be used to 3D print a copy of the scale model. There are detailed assembly instructions and a parts manifest at the top of that file. Be warned that the central frame part is larger than most 3D printers- it should be possible to change the scale factor (variable X) to a smaller number (e.g. 25.4/11 or 25.4/12 for 1/11 or 1/12th scale, respectively) to make it fit on your printer's bed, although I have not tested that everything fits together at other scales. You may also need to adjust the margin and innermargin variables for your printer.

Dependencies

Requires that ROS be installed (tested on ROS Kinetic Kame on Ubuntu 16.04), and requires the following ROS packages:

• Joy: sudo apt-get install ros-kinetic-joy
• ROSSerial: sudo apt-get install ros-kinetic-rosserial
• ROSSerial_Arduino: sudo apt-get install ros-kinetic-rosserial-arduino
• ROSBridge: sudo apt-get install ros-kinetic-rosbridge_suite

Requires that the Arduino IDE be installed: sudo apt-get install arduino

For the CAN stuff [in progress]

• CANard

  git clone https://github.com/normaldotcom/CANard.git

  cd CANard

  [sudo] python setup.py install

• (if using SocketCAN) can-utils: sudo apt install can-utils

• (if using SocketCAN) slcan kernel module, if not already built instructions.

The CANard module requires Python 3 (todo: figure out why), while the default ROS Python support in Kinetic is Python 2. You may need to specially install Python 3 moduels for ROS:

`sudo apt-get install python3-catkin-pkg-modules`

`sudo apt-get install python3-rospkg-modules`

Firefox

The GUI requires Firefox. Unfortunately, Firefox 53 and later are broken on Raspberry Pi MATE Ubuntu. To install, first uninstall Firefox, then download and install version 52:

sudo apt-get purge firefox
wget 'http://ports.ubuntu.com/pool/main/f/firefox/firefox_52.0.2+build1-0ubuntu0.12.04.1_armhf.deb'
sudo dpkg -i firefox_52.0.2+build1-0ubuntu0.12.04.1_armhf.deb
sudo apt-mark hold firefox

Running the code

There is a launch file that starts up all the required ROS nodes:

roslaunch tycho tycho.launch

Once the roslaunch file has finished, go to the web/index.html file in Firefox to view the GUI interface.

Controls

On an XBox 360 controller, the controls are as follows:

• Left stick: Drive and steer
• A button: Enable driving in reverse (otherwise pulling stik back brakes)
• B button: Change steering mode to strafing
• X button: Emergency stop (disabled by allowing stick to return to neutral)

Useful command-line snippets

Rebuilding ROS Arduino libraries:

source ~/catkin_ws/devel/setup.bash      # Must re-source the workspace, even if you already have?
rm -rf ~/sketchbook/libraries/ros_lib/   # Need to delete the libraries before rebuilding them
rosrun rosserial_arduino make_libraries.py ~/sketchbook/libraries/