Tiberius - an introduction¶

Tiberius is the name of a robotics R&D platform developed by J.T Herd and his Masters students at Heriot-Watt University.

Tiberius II Development Platform

Installation¶

The tiberius-robot package can be fully installed by running the setup script, found in the top level folder. The setup.py script attempts to install all necessary dependencies for tiberius-robot.

Tutorials - an introduction¶

Please find the following tutorials useful. Each tutorial is designed to be as unambiguous as possible

Getting Started¶

The following tutorial will guide you through all the steps necessary to build a system using compatible hardware, and getting the system up and running. The instructions are ordered with the biggest steps at the start, so you don’t get a head of yourself doing the easy bits at the beginning. In summary, in order to get a robot up and running you will need to set up a network, make sure you have compatible hardware, get a hold of our software, and configure our software for your hardware.

1. Installing compatible hardware

The following pieces of hardware have been tested to work with the Tiberius Software Suite:

• Raspberry Pi 1A+,1B,1B+,2B,3B
• NEO-M8N (GPS Module, serial interface)
• CMPS11 (Tilt Compensated Compass, I2C interface supported)
• RPLIDAR (LIDAR, basic scan supported)
• MD03 (Motor Driver, I2C interface supported)
• RAMPS (3D Printer Driver Board, used to drive our robotic arm, serial interface)

The exact model of DC motors used is not important, we have used wiper motors and motors from Como Drills.

Our software assumes you’ll have four driven wheels, any other number of wheels will require modification of the software. However this shouldn’t be too difficult - modification of actuators.py to add or remove motors.

Here two of our vehicles to get an idea of what we’re talking about:

Tiberius II

Tiberius III

A thorough hardware installation tutorial is available.

2. Getting a hold of the Tiberius software repository

Once you have some hardware, you can think about getting a copy of our software. The way we would normally go about this is connecting the Raspberry Pi to the internet, through your LAN. The the separate tutorial (Networking Tutorial) for network configuration instructions.

Note

It is essential to clone our git repository into into /home/pi/git/. This should result in the following folder being created:

/home/pi/git/tiberius-robot/

This is due to the hardcoded path names that are used in setup.py, in order to move files into a known location. Yes, we know, we know. This is not by any means ideal, but it is what currently works. This is an area that could be looked into if you feel like contributing.

Here’s an example of the commands that we use to clone our repository (assuming that you are currently in your home directory):

cd git/
git clone https://github.com/IonSystems/tiberius-robot.git

2. Installing the Tiberius Software Suite

Now that you have the hardware and have cloned the repository, you can now think about installing our software.

Note

We have tried to make our setup script as thorough and reliable as possible, although we cannot guarantee success. Unless you have done some funny things to file permissions, it should work.

You should now locate yourself in the top level of our repository using cd tiberius-robot/. You can then run the setup script by typing sudo python setup.py install. They above commands are provided below for copy-paste convenience:

cd tiberius-robot/
sudo python setup.py install

3. Configuring your installation

A number of configuration settings need to be edited to suit the particulars of your hardware setup. The configuration directory is the same for every installation, so your config file should appear in /etc/tiberius/tiberius_conf.conf

It is important to ensure the correct hardware is enabled, and unavailable hardware is disabled. As this configuration file is used by the software to determine whether or not to communicate with the respective device. The configuration file is also used by the API to decide whether or not to allow access to the particular device through the API.

It is also important to ensure the correct ports are set for the enabled devices. There is a test script to detect the USB devices available here: tiberius/testing/scripts/gps_dev_path. An alternative approach would be to run start_tiberius.py and you’ll know if the ports are wrong if you see error messages for the device in question.

Last, but not least, ensure the I2C addresses are set correctly. To list all I2C slaves on the bus, run i2cdetect 1. You’ll need to work out the correspondence between the addresses and the devices by process of elimination, or by reading data sheets for default addresses.

4. Getting the software running

This should be the easy part! We have a script in the top level of our repository called start_tiberius.py. This script takes care of starting everything in the correct order. If this starts successfully, then there is a good chance that everything is now operational.

For a more in-depth discussion of what start_tiberius.py does, see docstrings.

Networking¶

Hardware Installation¶

User Guides - an introduction¶

Tiberius the name of a robotics R&D platform developed by J.T Herd his Masters students at Heriot-Watt University.

Using the quickstart.py script¶

quickstart.py is located in the top level directory of this package, and provides shortcuts to common applications for convenience.

Tiberius’s Database Module¶

#Create a new Database
db = PolyhedraDatabase('example_db')

#Create a table with a few columns.
db.create('example_table', {'id': 'int primary key', 'example_column':'varchar(100)'})

#Insert a row into the table
db.insert('example_table', {'id': 0, 'example_column':'Example text value.'})

#Query the table for all rows an columns
results = db.query('example_table', '*')
print results

#Update the value we previously put in
db.update('example_table',
        {
            'example_column': 'Example new updates value.',
        },
        {
            'clause':'WHERE',
            'data': [
                {
                    'column' : 'id',
                    'assertion' : '=',
                    'value': '0'
                }
            ]
        })

#Drop the table
db.drop('example_table')

Tiberius’s Architecture¶

System Architecture Diagram¶

The following diagram illustrates an example system utilising our central database architecture:

Example System Architecture

Our database engine of choice is Polyhedra Lite, the free version of a commercial in-memory database. Although we have developed a Python wrapper class that creates a common Python interface between any database engine with minimal effort required.

Testing¶

tiberius package¶