Optical flow sensor HereFlow
HereFlow brings optical flow, a lidar and an IMU to your drone on a board no bigger than a finger. It watches the ground and the distance below, helps with precise landings and fits under almost any frame without taking up space. One CAN cable is all it needs, and the whole setup in Mission Planner takes just a few parameters, so it is ready to fly in no time.
Optical flow sensor HereFlow — Three Sensors on a Finger-Sized Board
HereFlow from CubePilot puts an optical flow camera, a lidar and a 6D IMU (ICM20602) on one board measuring only 28.8x9.5mm. The flow camera sees the ground from 80mm up, has a 42° field of view and follows movement up to 7.4rad/s. The lidar is a power efficient time-of-flight range finder with ST FlightSense technology. Within 2m it measures the distance in 5ms, with ±3% accuracy, and the result does not depend on the colour or reflectivity of the surface. HereFlow talks to the flight controller over CAN and can sit on any node of the CAN bus without noise problems. It is powered with 5V, works from -20 to 70°C and is set up in ArduPilot through Mission Planner. A CAN cable is included.
Orders exceeding current stock levels will be fulfilled within 10 weeks
Optical flow sensor HereFlow Key Features
Finger-Sized
It measures only 28.8x9.5mm. You can fit it almost anywhere under the drone without taking much space.
Three Sensors in One
An optical flow camera, a lidar and an IMU on one board. One module and one cable instead of three.
Anywhere on the CAN Bus
It connects over CAN and can sit on any node of the bus without noise problems.
Help with Precision Landing
CubePilot added the lidar because it is very useful for detecting the moment of a precise landing.
What Is on the Optical flow sensor HereFlow Board
Optical Flow Sensor
Watches the ground and measures how the drone moves over it. It works from 80mm up and needs at least 60lux of light.
Lidar
Measures the distance to the ground up to 2m, up to 50 times per second, with an invisible 940nm Class 1 emitter.
6D IMU (ICM20602)
A built-in inertial module that measures the movement of the board itself.
Setting Up the Optical flow sensor HereFlow in ArduPilot
CubePilot describes the setup in Mission Planner, with the flight controller connected to the computer over USB. All parameters are in the Full Parameter List.
1. CAN
| CAN_P1_DRIVER | 1 | turns on CAN |
2. Range Finder
| RNGFND_TYPE | 24 | turns on the range finder |
| RNGFND_MAX_CM | 200 | maximum distance |
| RNGFND_MIN_CM | 5 | minimum distance |
3. Optical Flow
| FLOW_TYPE | 6 | turns on the flow camera |
Click Write Params, then in Flight Data > Actions choose PREFLIGHT_REBOOT_SHUTDOWN and Do Action to restart the controller.
4. Check
In the Status tab, change the height of the drone and watch sonarrange. Then move the drone and watch opt_m_x, opt_m_y, opt_x and opt_y. If the values do not change, check the parameters or restart the controller.
Optical flow sensor HereFlow Manufacturer Notes
- The built-in lidar is not suitable for measuring height outdoors above 0.5m, or indoors above 2m.
- For accurate optical flow navigation CubePilot recommends a separate lidar, such as the Lightware SF11B or a similar one.
- Without a range finder you can use the FLOWHOLD mode in ArduCopter, which holds position with optical flow.
Installing the Optical flow sensor HereFlow
CAN Cable
Connect the CAN port of the module to the flight controller with the 4-pin CAN cable.
Y Axis to the Nose
Point the Y axis of HereFlow towards the nose of the aircraft.
Camera Facing the Ground
Stick the module to the bottom of the drone with 3M tape, or with a soft sticker for slight vibration isolation.
Nothing Under the Module
The bottom of the module must stay clear, otherwise the measurements are affected.
Hold It by the Edge
Do not touch the electronic components on the board. Hold it by the edge during installation.
Other CubePilot Products
More CubePilot devices for your drone.
CubePilot Documentation
The documentation for this product is on the manufacturer's website.
Optical flow sensor HereFlow Specification
Manufacturer | CubePilot |
Manufacturer Code | HX4-06076 |
Size | 28.8x9.5mm |
Interface | CAN |
Power Supply | 5V |
Operating Temperature | -20 to 70°C |
IMU | 6D, ICM20602 |
Optical Flow Range | 80mm to infinity |
Optical Flow Field of View | 42° |
Maximum Movement Speed | 7.4rad/s |
Minimum Illumination | over 60lux |
Lidar Measuring Frequency | up to 50Hz |
Lidar Field of View | 27° |
Lidar Maximum Distance | 2m |
Lidar Accuracy | ±3% |
Infrared Emitter | 940nm, invisible, Class 1 |
Optical flow sensor HereFlow Package Includes
- 1x HereFlow
- 1x CAN Cable