6.2 Calibration of Sensors
Sensors are important in the working of a drone. Every sensor should respond to the respective input with excellent efficiency and time response. There should not be any lag in the response of the system. For availing the better performance from the sensors, one should calibrate these before the flight.
RPA Configuration -Sensors
The Sensor Setup section allows you to configure and calibrate the vehicle's compass, gyroscope, accelerometer and pressure.
Under this setting, you can calibrate the accelerometer of the device. Once you click on the ‘Calibrate' button you would be asked to hold the vehicle in various orientations. Follow the instructions popped on the screen and calibrate the accelerometer.
Select the "Compass" tab first. Click on "Calibrate" button. Follow the instructions displayed on the screen. You need to rotate the vehicle randomly around all axes until the progress bar fills all the way to the right and the calibration completes.
Calibration of Compass
Note: While the vehicle is armed, compass calibration is not possible.
Compass Declination: – The angle formed by the compass's deviation from true north is referred to as "declination" (or "magnetic declination"). Set the compass declination value in radian. The minimum value allowed is -3.14 and the maximum value allowed is +3.14 .
- Select the required option from the dropdown menu.
- Click on the "Update" button to send the parameters to the device.
- Set Compass Fitness to "Relaxed" if compass calibration fails.
If the horizon is not level after completing accelerometer calibration you can calibrate the level horizon for your vehicle. You will be asked to place and hold your vehicle in level orientations while it captures orientation.
Calibration of Level Horizon
Note: Leveling the horizon is highly recommended for optimal flight performance. If you notice a persistent drift during flying, repeat this procedure.
Level Horizon Calibration is used to compensate for minor misalignments in controller orientation as well as to level the horizon in ground control flyview.
After the orientation is established and the level-horizon calibration is complete, check in the flight view that the heading in the compass is around 0 when you point the vehicle towards the north and that the horizon is level.
This calibration sets the altitude to zero at the current pressure.
Calibration of Pressure Sensor
Click on "Calibrate" button to calibrate the Barometer - pressure sensor used in a drone. The system will carry out the process of calibration. On successful completion of the calibration process, the "Barometer calibration complete" message will be displayed.
Calibration of Flow Sensor
This section allows to you configure flow-related parameters.
For estimating the velocity, Optical Flow employs a downward-facing camera and a distance sensor. These may be linked using MAVLink, I2C, or another bus that facilitates the peripheral.
Configuration options are as below:
- Flow Enable – To enable the flow select "Enable" otherwise select "Disable" from dropdown options.
- X axis correction factor – This factor is required to control the movement either in right or left direction on X-axis. Negative values of the X-axis correction factor indicate right movement and positive values of the X-axis correction factor indicate left movement.
- Y axis correction factor – This factor is required to control the movement either in the forward direction or backward direction on Y-axis. Positive values indicate the movement in the forward direction whereas, negative values of this factor indicate the movement in the backward direction on Y-axis.
- Flow sensor yaw alignment – The deviations in the center positions of the device is controlled by this factor.