ark-flow

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../../.gitbook/assets/SAM_0829 (Large).JPG	0

ARK Flow

ARK Flow is an open source DroneCAN optical flow, distance sensor, and IMU module.

Hardware Specifications

• Open Source Schematic and BOM
• Sensors
  • PixArt PAW3902 Optical Flow Sensor
    • Tracks under super low light condition of >9 lux
    • Wide working range from 80mm up to 30m
    • Up to 7.4 rad/s
  • 40mW IR LED built onto board for improved low light operation
  • Broadcom AFBR-S50LV85D Time-of-Flight Distance Sensor
    • Integrated 850 nm laser light source
    • Field-of-View (FoV) of 12.4° x 6.2° with 32 pixels
    • Typical distance range up to 30m
    • Operation of up to 200k Lux ambient light
    • Works well on all surface conditions
    • Transmitter beam of 2° x 2° to illuminate between 1 and 3 pixels
  • Bosch BMI088 6-Axis IMU or Invensense ICM-42688-P 6-Axis IMU
• STM32F412CEU6 MCU
• Two Pixhawk Standard CAN Connectors (4 Pin JST GH)
• Pixhawk Standard Debug Connector (6 Pin JST SH)
• Software-toggleable built in CAN termination resistor
• Small Form Factor
  • 3cm x 3cm x 1.4cm
• LED Indicators
• USA Built

LED Meanings

You will see both red and blue LEDs on the ARK Flow when it is being flashed, and a solid blue LED if it is running properly.

If you see a solid red LED there is an error and you should check the following:

• Make sure the flight controller has an SD card installed.
• Make sure the Ark Flow has ark_can-flow_canbootloader installed prior to flashing ark_can-flow_default.
• Remove binaries from the root and ufw directories of the SD card and try to build and flash again.

Video

Video

{% embed url="https://www.youtube.com/watch?v=SAbRe1fi7bU&list=PLUepQApgwSozmwhOo-dXnN33i2nBEl1c0&t=1s" %} PX4 holding position using the ARK Flow sensor for velocity estimation (in Position Mode). {% endembed %}

Pinout

CAN - 4 Pin JST-GH

Pin Number	Signal Name	Voltage
1	5V	5.0V
2	CAN_P	5.0V
3	CAN_N	5.0V
4	GND	GND

CAN - 4 Pin JST-GH

Pin Number	Signal Name	Voltage
1	5V	5.0V
2	CAN_P	5.0V
3	CAN_N	5.0V
4	GND	GND

Debug - 6 Pin JST-SH

Pin Number	Signal Name	Voltage
1	3.3V	3.3V
2	USART2_TX	3.3V
3	USART2_RX	3.3V
4	FMU_SWDIO	3.3V
5	FMU_SWCLK	3.3V
6	GND	GND

Firmware

{% file src="../../.gitbook/assets/80-1.16.3c45b562.uavcan.bin" %} ARK Flow Firmware {% endfile %}

{% file src="../../.gitbook/assets/ark_can-flow_canbootloader.bin" %} ARK Flow Bootloader {% endfile %}

Release Notes

• 80-1.16.3c45b562 - 2025-9-26
  • Migrate to build server
• 80-1.16.afb2c08b - 2025-8-6
  • AFBRS50: Fix long range measurement publishing
• 80-1.16.2248a40e - 2025-7-10
  • AFBRS40: fix Range Mode switching
• 80-1.16.d0bfa548 - 2025-6-12
  • AFBRS50 fix scheduling and refactor
• 80-1.15.82ff8744 - 2025-6-11
  • Add DroneCAN RawIMU publisher
• 80-1.16.61036f77 - 2025-2-7
  • Update to AFBR 1.6.5 API
    • Improved distance sensor performance