rpyBot

Software for controlling a raspberry pi robot using (mostly) python

Installation

You can install via PyPi or by downloading the project from github:

• via pip: pip3 install rpyBot
• via github:
  • git clone https://github.com/harmsm/rpyBot
  • cd rpyBot
  • sudo python3 setup.py install

Both methods should automatically install the dependencies:

• rpi.GPIO
• tornado
• PyCmdMessenger

You'll probably want to clone the project no matter what, as the rpyBot/example-configs/ directory has example robot configuration files that should be handy.

Quick Start

rypBot works by reading in a configuration file that describes what hardware is attached to the raspberry pi, building an html/javascript front end to control that hardware [under development!], and then serving that website.

Consider a lame robot that is a single LED connected to GPIO pin 12.

The appropriate configuration file would be:

from rpyBot import devices
from rpyBot.devices import gpio

device_list = [ 
    gpio.IndicatorLight(control_pin=12,name="attention_light",frequency=1,duty_cycle=50),
]

To start the robot up, you would cd into the directory with the configuration file, and then execute:

sudo rpyBot configuration.py > log.txt

(You have to run as root so rpi.GPIO can access the gpio pins. )

Assuming the raspberry pi is on a network with an ip address of 192.168.1.100, go to a browser on some device that is on the same network and type:

192.168.1.100:8081

into the address bar. This should bring up a browser with a single button that, when pushed, makes the light turn on.

To make things more interesting, start attaching other hardware to the gpio pins (or via USB/arduino, or ...) and then adding devices to the device_list.

Devices

• connect(manager): put the device under control of a DeviceManager instance
• disconnect: disconnect from the DeviceManager instance.
• start
• stop
• put
• get

Current device list

• rpyBot.devices.gpio
  • IndicatorLight
  • SingleMotor
  • TwoMotorDriveSteer
  • TwoMotorCatSteer
  • RangeFinder
• rpyBot.devices.arduino
  • TwoMotorCatSteer
  • LIDAR [coming soon]
• rpyBot.devices.web
  • WebInterface

Creating a new device

Devices are created as subclasses of the rpyBot.devices.RobotDevice.

• Hardware

  • GPIO: rpyBot/rpyBot/devices/gpio/hardware/
  • arduino/usb: rpyBot/arduino-code/

• Devices

  • GPIO: inherit from rpyBot.devices.gpio.GPIORobotDevice. Devices are defined in rpyBot/rpyBot/devices/gpio
  • arduino: inherit from rpyBot.devices.arduino.ArduinoRobotDevice. Devices are defined in rpyBot/rpyBot/devices/arduino

• Javascript interface

Asynchronous messaging specification

Messages are passed in an asynchronous fashion using the RobotMessage class (implemented in both js and python). This class allows specification of a destination_device and source_device (for routing), a delay_time for waiting to send the message and message itself.

On the pi side, the main instance of the DeviceManager class routes each message to the appropriate device name. For example, if m.destination_device == "attention_light", the DeviceManager will pass the message to the device named attention_light. On the web controller side, messages are routed using the sendMessage and recieveMessage functions.

What actually goes through the web socket is a string with the form:

destination.destination_device|source.source_device|delay_time|message

(destination and source are currently ignored). The robot devices and controller functions should never directly access or manipulate this string, but rather use instances of the class RobotMessage.