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ZED-F9R - Application note 

UBX-22035176 - R01 

Contents

 

Page 11 of 30 

C1-Public  

 

3

 

Installation 

The first step of setting up the ZED-F9R is installing it into the vehicle. Proper installation is vital for 
the  navigation  performance of the receiver, as its internal sensors must be able to measure the 
dynamics of the vehicle accurately in a consistent way. This means the antenna and receiver must be 
mounted rigidly in a fixed position and orientation relative to the vehicle’s body. 

 

Figure 5: Conceptual system view with good alignment 

3.1

 

Mounting the receiver 

Start by finding a suitable location in the vehicle to mount the receiver. The placement of the receiver 
does not matter in most applications. For best performance, the receiver should be placed as close to 
the center of the vehicle’s rear axle as possible. If the application’s accuracy requirements are very 
demanding, an advanced configuration may be needed. 

Next, plan the orientation of the receiver. Figure 6 shows the inertial measurement unit (IMU) frame 
and the installation frame. The default assumption is that the x, y and z axes of the IMU frame are 
parallel to the x, y, and z axes of the installation frame. The IMU frame orientation is printed on the 
label of the C102-F9R evaluation kit; for custom designs refer to Figure 7. For the simplest possible 
installation, mount the receiver in the orientation described above. If the receiver is mounted in any 
other orientation, a custom configuration must be set for correct performance. 

 

Note that the configured misalignment must be within 3 degrees of the truth to prevent 
significant degradation in navigation performance. A misalignment of tens of degrees will result 
in failure. Consult section 3.2.3 of the ZED-F9R Integration manua

[1]

 for more information about 

the IMU alignment. Configuring the misalignment is described in section 6.2.2. 

Содержание ZED-F9R

Страница 1: ...precision sensor fusion Application note Abstract This application note leads the user through the steps necessary to evaluate and prototype a sensor fusion based system using the ZED F9R The documen...

Страница 2: ...nd designs included in this document Copying reproduction or modification of this document or any part thereof is only permitted with the express written permission of u blox Disclosure to third parti...

Страница 3: ...anced Configuration view 9 3 Installation 11 3 1 Mounting the receiver 11 3 2 Mounting the antenna 13 3 3 Connecting cables 13 3 4 Setting up UART configuration 13 4 GNSS setup 14 4 1 Verifying GNSS s...

Страница 4: ...pendix 25 A 1 Recording logs 25 A 2 Replaying logs 25 A 3 Interference of GNSS signals 25 A 4 Communications and protocols 26 A 5 Basic alignment position offset checks 27 A 6 Odometry data issues 27...

Страница 5: ...owing items are required for completing the setup in this guide An operational ZED F9R module A suitable multiband GNSS antenna A host PC running u center for F9 products Serial communication between...

Страница 6: ...icle This information is usually available from a vehicle either as wheel ticks or speed measurements The data is typically generated by sensors that can measure the rotation of the vehicle s wheels s...

Страница 7: ...eceiver and verify that the connection works 1 Power on the receiver 2 Connect the receiver to the host with a serial or USB cable 3 Open u center on your PC 4 In u center select the correct serial po...

Страница 8: ...ate completed successfully 7 The new firmware version can be confirmed with the UBX MON VER message Figure 2 u center firmware update 2 3 Storing configuration settings ZED F9R is fully configurable w...

Страница 9: ...the window Figure 3 UBX CFG VALSET message During the evaluation phase it is most simple to write the configuration directly to flash During development and series production it is recommended to wri...

Страница 10: ...g the evaluation phase it is most simple to write the configuration directly to flash During development and series production it is recommended to write the configuration to the RAM or BBR layer at s...

Страница 11: ...cation s accuracy requirements are very demanding an advanced configuration may be needed Next plan the orientation of the receiver Figure 6 shows the inertial measurement unit IMU frame and the insta...

Страница 12: ...ZED F9R Application note UBX 22035176 R01 Contents Page 12 of 30 C1 Public Figure 6 IMU frame and installation frame Figure 7 Orientation information Z axis points upwards...

Страница 13: ...diameter 3 3 Connecting cables Connect all the necessary cables i e power antenna serial communication etc to the receiver Verify that the receiver is operational by repeating the procedure in 2 1 Onc...

Страница 14: ...receiver to reach a 3D fix 4 Check the available satellite signals in the Satellite Level view by clicking View Docking Windows Satellite Level Figure 8 u center Satellite Level view Under open sky co...

Страница 15: ...GNAL group A constellation is enabled when the constellation s enable key and both the L1 and L2 band keys are set to 1 Disabling a constellation can be done by setting the constellation s enable key...

Страница 16: ...other users are available for use For production grade applications more robust commercial services are recommended Start using the u center NTRIP client with the following steps 1 Open u center and c...

Страница 17: ...ce This includes authentication ancillary services like AssistNow service key delivery and the actual service u center implements a MQTT client Start using the u center MQTT client with the following...

Страница 18: ...TK status in u center see Figure 15 In the general information view View Docking Windows Data the RTK status is shown in the Fix status field as Float or Fixed if RTK is used Alternatively in the UBX...

Страница 19: ...of travel The direction is indicated with its own bit in the input message Wheel ticks can be input from either a single source single tick or from both the rear left and rear right wheel of a vehicl...

Страница 20: ...n the beginning and the two byte checksum in the end The complete message is sent to the receiver with the GpsInterface send_raw function When wheel tick messages are being delivered to the receiver u...

Страница 21: ...alignment Automatic IMU mount alignment allows the receiver to estimate the roll pitch and yaw angles based on the vehicle s movements This mode is only available when using the automotive dynamic mo...

Страница 22: ...RLM model set the wheel tick scaling factor with CFG SFODO FACTOR The factor is the distance per one tick in micrometers The wheel tick scaling factor can be determined by dividing the distance travel...

Страница 23: ...ING In this phase the receiver produces a GNSS only output During the initialization phase the receiver does the following steps IMU initialization Unknown crucial IMU parameters such as sensor sampli...

Страница 24: ...open sky conditions To see every stage of the receiver s operations the test drive should start with a cold start This way it is possible to analyze the time to first fix TTFF time to calibration and...

Страница 25: ...r allows the log to be loaded and various aspects of the drive scenario to be inspected in an offline mode Basics of replay include 1 To open a log file select File Open 2 Set up the Views relevant to...

Страница 26: ...n UART1 the byte counter should be increasing for both the transmit and receive direction If the protocol byte counters are not incrementing on the interface as expected this could mean that either th...

Страница 27: ...turn of arc length of 1 m to the right and continue straight The recordings during the turn should be smooth without sawtooth like patterns Repeat for a left turn If the sawtooth patterns are always o...

Страница 28: ...more than 20 satellites visible under open sky Are there many signals with a CNO level between 40 and 50 dB Are all four constellations reporting signals Are there two signals on many of the signals D...

Страница 29: ...blic Calibration related Is the calibration drive suitable for the vehicle type Did the calibration drive result in a calibrated and initialized system Final test During the test drive after calibrati...

Страница 30: ...ool available in https compsci290 s2016 github io CoursePage Materials EulerAnglesViz For product change notifications and regular updates of u blox documentation register on our website www u blox co...

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