> For the complete documentation index, see [llms.txt](https://docs.arkelectron.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arkelectron.com/products/sensor/ark-flow-lr.md).

# ARK Flow LR

The ARK Flow LR is a [DroneCAN](https://dronecan.github.io/) optical flow and long-range distance sensor module, with a [PixArt PAA3905](https://www.pixart.com/products-detail/108/PAA3905E1-Q_) optical flow sensor, a Broadcom AFBR-S50EX85D time-of-flight distance sensor and an [InvenSense IIM-42653](https://invensense.tdk.com/products/smartindustrial/iim-42653/) IMU. It is the [ARK Flow MR](/products/sensor/ark-flow-mr.md) with a longer-range distance sensor, and runs its own firmware. It works with PX4, ArduPilot and ROS 2 through [ros2\_dronecan](https://github.com/ARK-Electronics/ros2_dronecan). USA built and NDAA compliant.

[Buy the ARK Flow LR](https://arkelectron.com/product/ark-flow-lr/)

The distance sensor reports 0.6 to 100 m at 10 Hz. Range depends on the light on the ground and on the surface. See [Range](/products/sensor/ark-flow-lr/hardware.md#range).

| Page                                                                             | Contents                                                                 |
| -------------------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| [Firmware](/products/sensor/ark-flow-lr/firmware.md)                             | Updating, node parameters, downloads and release notes                   |
| [Hardware Reference](/products/sensor/ark-flow-lr/hardware.md)                   | Specifications, range, pinout, LEDs, wiring, mounting, 3D model and case |
| [PX4 Instructions](/products/sensor/ark-flow-lr/px4-instructions.md)             | Connecting and configuring with PX4                                      |
| [ArduPilot Instructions](/products/sensor/ark-flow-lr/ardupilot-instructions.md) | Connecting and configuring with ArduPilot                                |
| [DroneCAN Messages](/products/sensor/ark-flow-lr/dronecan-messages.md)           | Messages the ARK Flow LR publishes                                       |


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