OneASP Pro User Manual

Product Introduction

1. 24-bit analog-to-digital converter that performs calibration and temperature compensation for offset, sensitivity, and temperature-induced nonlinearity.
2. Maximum airspeed measurement of 439.9 km/h, meeting the airspeed measurement requirements for drones from low speed to subsonic speeds.
3. Uses DroneCAN bus communication, offering long transmission distance and strong anti-interference capability.
4. Adopts a twist-lock structure to ensure silicone tubes do not loosen.

Product Specification Table

Parameter	Value
Airspeed Measurement Range	0~439.9 km/h (122.2 m/s) (@15℃ 101325Pa standard atmospheric conditions)
Barometer	Yes
Total Error Band	±0.15% FS
Temperature Drift Performance	Low temperature drift, high accuracy
Silicone Tube Locking Structure	Yes
Interface Type	Automotive-grade 04R-JWPF-VSLE-S
Communication Protocol	DroneCAN bus communication, strong anti-interference capability
Flight Controller Compatibility	ArduPilot and PX4 flight controllers
Operating Voltage	4.7 - 5.3 V
Operating Temperature	-20℃ ~ 85℃
Housing Material	Aviation aluminum
Weight	40 g
Dimensions	78.6 × 39 × 15 mm

ArduPilot Airspeed Sensor Enablement and Calibration Tutorial

CAN Interface Configuration

Run Mission Planner and navigate to [Config] > [FULL Parameter List] interface. Set the following parameters, save, and restart the flight controller.

When connected to the flight controller's CAN1 interface:

• CAN_P1_DRIVER = 1
• CAN_D1_PROTOCOL = 1

When connected to the flight controller's CAN2 interface:

• CAN_P2_DRIVER = 1
• CAN_D2_PROTOCOL = 1

Airspeed Sensor Setup

• ARSPD_TYPE = 8 (Set to UAVCAN type)
• ARSPD_USE = 1 (Enable airspeed sensor)

Airspeed Zeroing (Offset Calibration)

⚠️ Note
The OneASP Ultra offers consistency advantages in general environments. This step can be skipped by setting ARSPD_SKIP_CAL = 1.

Manual Zeroing Steps

1. Connect Mission Planner to the flight controller.
2. Place the airspeed sensor in a wind-free environment.
3. Navigate to the [Flight Data] > [Actions] tab.
4. In the first checkbox, select "Preflight Calibration".
5. Click the "Do Action" button.

Pre-Flight Check

1. Static Check: In a wind-free state, the airspeed value should fluctuate within the range of 0~3 m/s. If it exceeds the range, re-perform the airspeed zeroing.
2. Dynamic Check: Hold the pitot tube and blow into it to confirm that the airspeed value changes with airflow.

Airspeed Auto-Calibration

Parameter Setting

• ARSPD_AUTOCAL = 1 (Enable auto-calibration)

Calibration Method (Choose One)

Method 1: FBWA Mode Calibration

1. Take off in QStabilize or QLoiter mode.
2. Switch to FBWA mode.
3. Fly the drone in circles for about 5 laps.
4. Wait for the "Calibration complete" message in the ground station message bar.
5. After landing, set ARSPD_AUTOCAL back to 0.

Method 2: Loiter Mode Calibration (Suitable for beginners)
⚠️ Note: Do not perform this in high-wind environments.

1. Set parameters: ARSPD_USE=1 and ARSPD_TYPE=8.
2. After takeoff, use Loiter mode to circle about 5 laps.
3. Wait for the calibration completion prompt, then land.
4. Set ARSPD_AUTOCAL back to 0.

PX4 Firmware Airspeed Sensor Configuration and Calibration Tutorial

Hardware Connection

Connect the OneASP L10D airspeed sensor to the flight controller's CAN1/CAN2 interface.

Parameter Setting

After flashing the PX4 firmware onto the flight controller, connect to the QGroundControl (QGC) ground station and set the following parameters in the parameter table:

• UAVCAN_ENABLE → Set to Sensors automatic Config
• UAVCAN_SUB_ASPD → Set to enable
• UAVCAN_SUB_DPRES → Set to enable

Restart and Notes

Restart the flight controller after settings are applied.

⚠️ Important Note: A memory card must be installed in the flight controller for the airspeed sensor function to work properly.

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Dual Airspeed Sensor Redundancy Configuration

When two airspeed sensors are installed on the drone, the data switching strategy can be configured via parameters:

• ASPD_PRIMARY → Configure the primary airspeed sensor data source.

Working Principle:

• The flight controller prioritizes checking whether the primary airspeed sensor data is normal.
• If the primary airspeed sensor data is abnormal or fails the check, it automatically switches to the secondary airspeed sensor.
• This ensures airspeed data reliability and enhances flight safety.

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Airspeed Calibration Process

Follow these steps in QGroundControl:
Calibration Steps

1. Navigate to Vehicle Setup → Sensors → Select Airspeed.
2. Click the airspeed sensor button to start calibration.
3. Protect the sensor from wind (cover the pitot tube with your hand), being careful not to block any holes.
4. Click "OK" to begin calibration.
5. Wait for the prompt "blow into front of probe without touching".
6. Blow into the front of the pitot tube; the prompt will display process <100>.
7. Wait for the prompt indicating calibration is complete.