bot_box

Bot Box

Bot Box is a client application for https://roboportal.io. It enables peer-to-peer controls, video and audio streaming between robots and web-based control panels. In other words, if you are building the robot and planning to add remote-control functionality and real-time video/audio streaming, it is worth considering using this service.

Features

• real time video and bidirectional audio streaming
• keyboard and gamepad controls streaming with data channel
• telemetry streaming to the platform. Position on map and battery voltage are supported
• connect robot via UART or ZeroMQ

How it works

Installation guide

1. Prepare SD card with Raspberry Pi OS image. How To guide for Raspberry Pi Imager. We don't need Desktop version for this application.
2. Enable camera, SSH (optional, but handy) and set up the WiFi with raspi-config. It also make sense to change the default password and set up the auto login. Default GPU memory allocation (128MB) might not be enough for real-time video converting / streaming, so it should be ~256MB. Documentation for raspi-config..
3. Install git, wget and other required packages (staring from this step you'll need an internet connection)

sudo apt update
sudo apt install git wget libatomic-ops-dev pkg-config libvpx-dev libopus-dev libopusfile-dev libasound2-dev libsodium-dev libzmq3-dev libczmq-dev

1. Install golang

Raspberry Pi OS 32 bit:

wget https://go.dev/dl/go1.21.0.linux-armv6l.tar.gz
sudo tar -C /usr/local -xzf go1.21.0.linux-armv6l.tar.gz
rm go1.21.0.linux-armv6l.tar.gz

Raspberry Pi OS 64 bit:

wget https://go.dev/dl/go1.21.0.linux-arm64.tar.gz
sudo tar -C /usr/local -xzf go1.21.0.linux-arm64.tar.gz
rm go1.21.0.linux-arm64.tar.gz

1. And configure it:

   • Open .profile nano ~/.profile
   • And insert this:

   PATH=$PATH:/usr/local/go/bin
   GOPATH=$HOME/go
   

   • save your changes and exit nano: Ctrl + O and Ctrl + X
   • apply your changes: source ~/.profile
   • check the installation: go version

2. Clone this repository to your Raspberry: git clone https://github.com/roboportal/bot_box.git

3. Navigate to the repo: cd ./bot_box

4. And compile the BotBox:

   • Raspberry Pi OS 32 bit: CGO_LDFLAGS="-latomic" go build -tags=arm
   • Raspberry Pi OS 64 bit: CGO_LDFLAGS="-latomic" go build -tags=arm64
   • Mac: go build

5. Create .env file for the configuration following the instructions.

6. Run the bot by executing: ./bot_box

BotBox configuration

All the configuration of Box Bot is done by setting up .env file. You can use .env_example as a staring point for your config. The list of params:

• srv_url - the WSS endpoint of roboportal.io
• public_key and secret_key - the key pair obtained after the bot creation
• stun_urls - comma-separated list of STUN servers URLs
• video_codec_bit_rate - bit rate for video codec
• frame_format - camera image format
• video_width - camera image width
• video_frame_rate - camera frame rate
• audio_input_enabled - enable audio streaming to roboportal
• audio_output_enabled - enable audio streaming form roboportal
• output_mode - destination for control commands: console | serial | ipc
• port_name - name of the serial port to communicate with robot hardware
• baud_rate - serial port baud rate
• bot_box_ipc_port - BotBox ipc port
• robot_ipc_port - robot ipc port
• robot_ipc_host - robot ipc host name
• camera_multiplexor_i2c_bus - i2c bus number for camera multiplexer device
• debug - enable additional logging

Supervisor setup

Let's setup supervisor. It will start Bot Box process after Raspberry Pi boot and handle restarts after possible application crashes.

1. Install the supervisor: sudo apt-get install supervisor
2. The next step is to setup supervisorctl for pi user: sudo nano /etc/supervisor/supervisord.conf
3. Under the section [unix_http_server] modify and create this:

chmod=0770
chown=root:pi

1. Create the config file for Bot Box: sudo nano /etc/supervisor/conf.d/bot-box.conf
2. Add there the following:

[program:bot-box]
command=/home/pi/bot_box/entrypoint.sh
directory=/home/pi/bot_box
autostart=true
autorestart=true
user=pi
killasgroup=true
stopasgroup=true

1. To start the bot box run supervisorctl start bot-box. There are some handy commands:

• supervisorctl stop bot-box
• supervisorctl restart bot-box
• supervisorctl tail -f bot-box stdout
• supervisorctl tail -f bot-box stderr

Messages format

bot_box communicates with robot via JSON serialized messages.

Robot controls formats

Typical control message has the format: {"address": a, "controls": m}.

Address

In such message address 'a' is an integer number: 0 or 1. 0 is a default value, 1 is applicable to the second control in a 'Fight Mode'. When 'Fight Mode' is disabled address could be ignored by the robot hardware.

Controls

Controls message 'm' contains a payload of commands for robot hardware to execute.

For example:

• Enable controls - {"address":0,"controls":{"start":true}} - this message will be sent to robot after 'Controls' are enabled in RoboPortal UI.

• Disable controls - {"address":0,"controls":{"stop":true}} - this message will be sent to robot after 'Controls' are disabled in UI or interrupted p2p connection.

• Control command - {"address":0,"controls":{"l":0,"r":0,"f":100,"b":0}} - such payload is defined by 'Controls Setup' in RoboPortal application by setting key-value pairs. The message above is used in 'Scout' robot example. It represents 'Move Forward' command.

Telemetry

Robot could send it's location and battery data to be presented to user as widgets using following format:

{
  "id": 0,
  "location": {
    "lat": 49.2766275048836,
    "lng": -123.13133235249737,
    "headingAngle": 90
  },
  "battery": {
    "min": 18,
    "max": 25.2,
    "value": 24,
    "uom": "V",
    "charging": False
  },
  "genericData": {
    "customKey": "customValue"
  }
}

id - id of the robot, check 'Controls' section

GPS (as location object):

lat - latitude lng - longitude headingAngle - magnetic compass angle

Battery (as battery object):

min - minimum possible value max - maximum possible value value - current value (charge, voltage) uom - unit of measure for value (V, % etc) charging - is charging or not

Custom Data (as genericData object):

User specified key-value pairs to be displayed as text.

Camera multiplexer

The Bot Box can utilize a dual camera adapter for seamless camera switching during operation. This feature is particularly useful for navigation and arm camera control or for switching between forward and backward cameras. To enable this feature, users must simply enable the 'Camera SW' widget in the robot settings.

Media devices troubleshooting

• To enable Raspberry Pi Camera Module support on Raspbian Bullseye Legacy Camera Mode should be enabled with raspi-config.
• How to use USB audio devices with Raspberry Pi.

Community Projects

• How to Control a Robot using WebRTC - great tutorial on robot mania YouTube channel.

Design Examples

• Examples of robots built with roboportal

Video Tutorials

Visit the ROBOPORTAL YouTube channel for the tutorials.

Guides

Using with arduino and serial port

Contacts

Join our Discord channel or reach out over email: info@roboportal.io