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Lidar Mapping (PoC) »

Components

Last update: 2022-05-07


Table of Content

The system has 2 main parts:

  1. Rover System is mounted on an RC Car or Drone to scan an area and map the captured point-cloud.

  2. Base Station acts as a stationary point which provide positioning correction to Rover for better accuracy.

Rover System#

  • Livox Lidar Mid-40

    It’s better to get Converter 2.0

    • 100,000 points per second
    • POV: 38.4° circular
    • Upto 260m @ 80% reflectivity
    • Livox Converter 1.0: Power, Ethernet, Sync RS485.
  • Jetson Nano Developer Kit

    • CPU Quad-core ARM A57 @ 1.43 GHz
    • GPU 128-core Maxwell
    • RAM 4 GB 64-bit LPDDR4 25.6 GB/s
    • Gigabit Ethernet, M.2 Key E
    • 4x USB 3.0, USB 2.0 Micro-B
    • GPIO, I2C, I2S, SPI, UARTs
  • Micro-SD Card

    Should have 32 GB at high speed (V30) for saving point louds

    • Sandisk Ultra 16 GB, class 10, SDHC I
  • Unicorecomm GNSS UB482

    • GPS L1/L2 + BDS B1/B2 + GLONASS L1/ L2 + Galileo E1/E5b + QZSS L1/L2
    • Two antennas, support heading
    • 20 Hz data output rate
    • Ethernet, serial port, SPI, 1x PPS
  • Harxon HX-CH7604A antennas

    • All-constellation Multi-frequency L1/L2, G1/G2, E1, B1/B2/B3
  • SMA Female to MMCX Male

    UB482 has MMCX (Mini-MCX) Female connector
    HX-CH7604A has SMA Male connector

  • InvenSense DK-20789

    • 7-axis motion sensor
    • Embedded Microchip G55 MCU and debugger
    • Embedded Motion Drivers
  • Rechargeable Battery

    • 16 V with 2000 mAh
    • Peak current at 4 A
  • DC-DC Converter

    • Except Lidar, all other boards use 5V
    • Peak current at 4 A
  • USB WiFi dongle

    TP-Link WN725N

    • 150 Mbps 802.11 b/g/n, Internal antenna
    • Ad-Hoc / Infrastructure Mode
  • WiFi router

    No need this component if using a USB WiFi dongle connected to the Jetson board, and Lidar is connected directly with it.

    • 4-port LAN Router
  • 2 x Ethernet Cable

    • Either connect Lidar to the Router or connect to the Jetson board directly after setting up static IPs on both sides.
  • nRF24L01 2.4GHz Transceiver + PA + LNA

    • ISM 2.4 GHz, 126 Channels GFSK
    • 250 kbps, 1 Mbps và 2 Mbps
    • SPI interface to host MCU
    • PA + LNA for upto 1 Km range
  • USB TTL to RS485

    No need this component if using Livox Converter 2.0

    • 5 V operation, differential voltage >= 200 mV
  • 3x USB TTL to COM

    No need this component if using on-board UARTs port after reconfiguring OS kernel

    • 3.3 V/ 5 V USB to COM
  • OLED LCD

    Show system status without connecting to PC via WiFi

    • 128x64 Monochrome
    • I2C interface

Base Station#

  • Raspberry Pi 3 B+

    This can be repalaced by a MCU as Base only needs to log data and transmit RTCM3 messages

    • Broadcom BCM2837B0, Cortex-A53 (ARMv8) 64-bit SoC @ 1.4 GHz
    • 1 GB LPDDR2 SDRAM
    • 2.4 GHz and 5 GHz IEEE 802.11.b/g/n/ac wireless LAN, Bluetooth 4.2, BLE
    • Gigabit Ethernet over USB 2.0
    • 4 USB 2.0 ports
    • GPIO, I2C, I2S, SPI, UARTs
  • Unicorecomm GNSS UB4B0M

    • GPS L1/L2/L5 + BDS B1/B2/B3 + GLONASS L1/L2 + Galileo E1/E5a/E5b+ QZSS L1/L2/L5

      Should cover the same constellation system of the Rover

    • UARTs, 1x PPS

    • Onboard MEMS integrated navigation Confirmed by Unicorecomm: new products do no have MEMS due to lack of chips!
  • Harxon HX-CH7604A antennas

    • All-constellation Multi-frequency L1/L2, G1/G2, E1, B1/B2/B3
  • SMA Female to MCX Male

    UB4B0M has MCX Female connector
    HX-CH7604A has SMA Male connector

  • MicroSD Card

    • Sandisk Ultra 16 GB, class 10, SDHC I
  • Rechargeable Battery

    • 5 V with 2000 mAh
    • Peak current at 2 A
  • nRF24L01 2.4 GHz Transceiver + PA + LNA

    • ISM 2.4 GHz, 126 Channels GFSK
    • 250 kbps, 1 Mbps và 2 Mbps
    • SPI interface to host MCU
    • PA + LNA for upto 1 Km range
  • USB TTL to COM

    No need this component if using on-board UARTs port after reconfiguring OS kernel

    • 3.3 V/ 5 V to USB COM
  • OLED LCD

    Show system status without connecting to PC via WiFi

    • 128x64 Monochrome
    • I2C interface

Other stuff#

  • PCB boards, M2.5 and M3 Copper Cylinder, Bolts

  • STM32 Dev board

    • Emulate GNSS data when GPS is not available (in house, or cloudy days)
  • Header 2.0 mm, 2.54 mm

    • Unicorecomm GNSS modules use headers at 2.0 mm pitch
    • Jetson and Pi modules use headers at 2.54 mm pitch
  • Remote Control Car with large base

    Mount Rover on the car for testing


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