Interfaces

Mobile beacon ("hedge") interfacing protocol to robots

1. Via virtual UART via USB:
   • This is the easiest way to connect since no soldering is required and protocol is the same for different operating systems.
   • Hedge HW v4.5+ : USB protocol for mobile beacon - description of the USB protocol between mobile beacon and a host device for Windows and Linux
2. Via SPI:
   • SPI & UART interface pins on beacon board.
   • Hedge HW v4.5+ : USB protocol for mobile beacon - description of the USB protocol between mobile beacon and a host device for Windows and Linux
3. Python library for beacon:
   • Here is the Python code for Linux-based devices integration via virtual UART via USB
   • Library is easy to use. Also, here is detailed description and example
   • Code is fairly universal; Tested on:
     • Ubuntu 16.04
     • Raspbian Jessie
     • Mac (OS X 10.10)
     • Python v2.7
   • CRC calculation is done in "pythonic way", i.e. library crcmod is used
   • There are handlers of different exceptions, for example, non-standard states of COM/USB
   • The Python library provides quick and easy ability for integration of ultrasound navigation system with various linux-based devices. Among them are Raspberry Pi and other single-board PCs. This code is free to use in your applications (please include a reference link to this web page).
4. C library for beacon:
   • Here is the C code + guiding document
   • Supported operating systems:
     • Microsoft Windows
     • GNU/Linux (including Raspberry Pi)
     • Mac OS X
   • Additionally, link to Bitbacket repository
5. Connection of Marvelmind hedgehog to Arduino via UART and SPI:
   • The detailed description of connection to Arduino shield via UART and SPI is described in:
     • Hedge HW v4.5+ : the link
   • Arduino sample code - sending path to robot
   • Arduino sample code - get distances to beacons
   • Arduino sample code - UART interface
   • Arduino sample code - SPI interface
6. ROS support on Raspberry 2 and Raspberry 3:
   • Marvelmind ROS package - bitbucket link.
   • Marvelmind ROS package v1.0.6 compatibility and main changes:
     • Supports both millimeters and cantimeters (obsolete) formats of data
     • Supports hedgehog address in data stream. Can receive positions of multiple hedgehogs from modem
     • Supports receiving positions of stationary beacons
     • Supported ROS versions:
       • Kinetic for Ubuntu 16.04
       • Indigo for Ubuntu 14.04
       • Hydro for Ubuntu 12.04
   • Please, check the instructions on ROS integration.
   • ROS repository status.
   • Hints:
     • By default UART is not accessable. Use command: sudo chmod 0777 /dev/ttyAMA0 to enable it
     • Or a more elegant way: Set permissions for serial port by this instruction: http://raspberrypi.stackexchange.com/questions/48211/set-permission-for-dev-ttyama0-on-boot
     • Set correct UART speed on mobile beacon: Dashboard => Interfaces shall be set to 9600 bit/s
     • Additional hints:
       • https://www.cube-controls.com/2015/11/02/disable-serial-port-terminal-output-on-raspbian/
       • http://raspberrypi.stackexchange.com/questions/45570/how-do-i-make-serial-work-on-the-raspberry-pi3
7. Pixhawk support and NMEA interface description:
   • Please, check the instructions on Pixhawk integration and description of interfacing via NMEA0183 protocol.
   • Forum on PixHawk integration. There are more topics, though. Check the forum
8. Sending path to your robot/copter:
   • Here is an explanation how to send path data via mobile beacon to your robot/copter sample code.
   • Protocol description => 2.3.1. Request of writing the movement path
   • Relevant forum discussion