Data Sheet

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3.2 Mobile beacon a.k.a. “hedgehog”
- The mobile and stationary beacons can be easily
interchanged by selecting in the Dashboard
- The mobile beacons designed to be placed on a
robotic vehicle, copter/drone, AGV, or helmet to trace
its location. Formally speaking, location of the mobile
beacon is traced—not the robot itself. Since the sizes
and the location of the central point of the mobile
beacon and the robot are different, the difference
taken into account in the robot’s software (SW)
- It is recommended to place the mobile beacon
horizontally to provide optimal ultrasonic coverage in
the upper hemisphere
- Its sensors must not be covered with anything that can reduce the strength of ultrasonic
signal. For example, the system won’t normally work, if one puts the mobile beacon in a
plastic box
- The beacon’s coordinates are updated according to the rate set on the Dashboard
- The system may contain one or several mobile beacons. Current implementation relies on
a time-division multiple access approach. Thus, if two mobile beacons are activated, they
share the same system bandwidth. It means that, if the 16 Hz update rate is selected in the
Dashboard and there are 2 mobile beacons in the system, each beacon’s location will be
updated with the rate of 16Hz/2 ~ 8Hz. If there are 3 mobile beacons => 16Hz/3 ~ 5Hz, etc.
For 4 and more mobile beacons we recommend using Inverse Architecture. See more in
Architectures comparison
- Location data is obtained either from the “hedgehog” via USB (virtual UART), UART, SPI,
or from the modem/router via USB (virtual UART). More information on interfaces can be
found here (Mini-RX and Mini-TX beacons do not have pinouts, only over micro-USB)
- Data from the beacon sent in a streaming format identical to that of GPS (NMEA 0183)
- There are 433MHz and 868/915MHz (868/915MHz only for Mini-RX and Super-Beacon)
versions available. Proprietary radio protocol is used for communication and
synchronization
- The “hedgehog” has been successfully integrated with Windows PC, Linux machines,
Raspberry Pi, Arduino boards, Intel boards, etc.
Fig.1: Super-beacon as an example