Dynamic model

This page documents the dyn model configuration

By providing information on the application (in which the device is installed), the device will be able to provide a better output result. If the device is specifically installed in an automotive application, the device is further able to combine the GNSS and IMU data with a mathematical model of a generalized automotive vehicle to provide an improved combined result.

Configuration file fields

This section is autogenerated from the Rule Schema file.

Dynamic platform model sensor.dyn_model

Select the dynamic platform of the application in which the device is installed for an improved output result

Type

Default

Options

integer

0

Portable (default): 0 Stationary: 2 Automotive: 4 Sea: 5 Airborne with <1g acceleration: 6 Airborne with <2g acceleration: 7 Airborne with <4g acceleration: 8 Bike: 10

Sensor fusion sensor.dyn_model.sensor_fusion

Combines GNSS and IMU data for improved navigation performance particularly in places with poor GNSS signal conditions. Uses an automotive sensor fusion model. Requires accurate IMU alignment configuration and configuration of sensor lever arms.

Type

Default

Options

integer

0

Disable: 0 Enable: 1

Lever-arm configuration sensor.dyn_model.lever_arm

Defines the [X, Y, Z] offset from the Vehicle-Reference-Point to the mount position of the sensor

Vehicle-reference-point to antenna sensor.dyn_model.lever_arm.vrp_to_ant

X-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_ant.leverarm_x

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Y-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_ant.leverarm_y

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Z-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_ant.leverarm_z

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Vehicle-reference-point to module sensor.dyn_model.lever_arm.vrp_to_imu

X-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_imu.leverarm_x

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Y-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_imu.leverarm_y

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Z-coordinate (cm) sensor.dyn_model.lever_arm.vrp_to_imu.leverarm_z

Type

Default

Minimum

Maximum

integer

0

-32768

32767

Configuration explained

This section contains additional information and examples.

Dyn model

Knowing the application model improves the receiver’s interpretation of the measurements resulting in a more accurate position output.

The device supports the following dynamic models:

  • Portable[1]: Low acceleration applications

  • Stationary: Static applications (no position movement)

  • Automotive: Low vertical acceleration and dynamics equivalent to those of a passenger car

  • Sea: Zero vertical acceleration, sea-level applications

  • Airborne <1g: Higher dynamic range and vertical acceleration (compared to automotive)

  • Airborne <2g: Even higher dynamic range and vertical acceleration (compared to automotive)

  • Airborne <4g: High dynamic range and vertical acceleration (compared to automotive)

  • Bike: Low vertical acceleration and dynamics equivalent to those of a motor bike

Automotive sensor fusion

The CANmod.gps supports automotive-sensor-fusion, integrating measurements from the IMU and GNSS with an automotive dynamic model. The resulting sensor fusion output yields improved navigation performance, particularly in places with GNSS-denied conditions and outages.

Sensor fusion can only be enabled if the Automotive dynamic model is selected.

Warning

Sensor fusion is an advanced feature and requires careful configuration of the IMU-alignment angles and the lever-arms. If an accurate configuration cannot be provided, the result of the sensor fusion model can be worse compared to leaving the feature disabled.

The automotive sensor fusion model assumes a specific application installation coordinate system as illustrated below.

../../../_images/automotive_installation_coordinate_system.svg

Automotive installation coordinate system (right-handed). The X-axis points towards the front of the vehicle, the Y-axis to the left and the Z-axis up through the roof.

For the sensor fusion feature to work, the IMU coordinate system must be oriented as the automotive-installation-coordinate system. For more information on how to align the IMU output see the IMU mount alignment Section.

Lever arm

When the sensor fusion model is used, the device requires information on where the CANmod.gps and the GNSS antenna are installed in the vehicle if placed at a significant distance from the Vehicle-Reference-Point (VRP). The X, Y, Z distances from the VRP to the installation is denoted lever arm. The VRP is defined as the center of the vehicle’s rear axle as illustrated above.

Vehicle-Reference-Point to module / antenna

The module- and antenna to VRP lever arms are illustrated:

../../../_images/dyn_model_lever_arm.svg

The X, Y, Z distances (in cm) for both the CANmod.gps (module) and antenna should be entered in the configuration when sensor fusion is activated.