Sonardyne Lodestar AHRS, Operation Manual

Page 1: ... Sonardyne International Limited 2013 1 UM 8084 107 Lodestar AHRS Operation Manual Head Office Sonardyne International Limited Blackbushe Business Park Yateley Hampshire GU46 6GD United Kingdom T 44 0 1252 872288 F 44 0 1252 876100 E support sonardyne com www sonardyne com ...

Page 2: ...tility release Formatting changes ECN12243 New section File Transfer and updated Appendix A All 5 5 5 9 All All All All 6 10 and Appendix A All All All All All All All Copyright 2013 Sonardyne International Limited Blackbushe Business Park Yateley Hampshire GU46 6GD United Kingdom Tel 44 0 1252 872288 Fax 44 0 1252 876100 All rights reserved No part of this document shall be reproduced stored in a...

Page 3: ...13 4 1 Installation Preparation 13 5 Installation and Physical Configuration 15 5 1 Typical Lodestar AHRS configuration 15 5 2 Installation 17 6 Configuration using Lodestar PC Utility 18 6 1 Installation and Connection 18 6 2 System 19 6 3 Gyro Compass 22 6 4 Offsets 24 6 5 Console C1 C2 E1 T1 and T2 Ports 26 6 6 Ethernet and Ethernet E1 Ports 28 6 7 Analogue Output Tab 30 6 8 Time 31 6 9 Output ...

Page 4: ... 22 Figure 14 Automatic GPS Compensation Panel 23 Figure 15 Heave Filter Panel 23 Figure 16 Mounting Angles and Offsets Panel 24 Figure 17 Remote Points List 24 Figure 18 Port Settings Panel 26 Figure 19 Output Message Table 27 Figure 20 IP Port Configuration Panel 28 Figure 21 Ethernet Output Message Table 29 Figure 22 Analogue Port Tab 30 Figure 23 Clock Settings panel 31 Figure 24 ZDA Port Pane...

Page 5: ...ration Manual Document Ref UM 8084 107 A6 Issue A Rev 6 Sonardyne International Limited 2013 5 Tables Table 1 Lodestar ports to Software tab mapping 26 Table 2 Analogue Port output options 30 Table 3 PPS Input Ports 32 ...

Page 6: ...o section 4 Make sure the latest manuals and Lodestar Configuration Software are used Purpose of this manual The purpose of this Installation Manual is to introduce the Lodestar Configuration Software and to guide through a typical Lodestar set up The text and instructions in this manual assume the Lodestar Configuration Software is installed on a PC The instructions in this manual help to Configu...

Page 7: ... central reference point CRP For most applications measurements are required with respect to the vehicle s reference frame The definition of the Lodestar reference frame with respect to a vehicle is shown in Figure 1 Figure 1 Lodestar Reference Frame The Lodestar frame is a fixed right hand coordinate frame X Y Z Typically Lodestar is mounted so the X axis is approximately coincident with vehicle ...

Page 8: ...e to the actual Lodestar frame is 1 Rotation by the gamma heading angle about the Z axis of the reference frame 2 Rotation by the beta pitch angle about the resulting Y axis 3 Rotation by the alpha roll angle about the resulting X axis CAUTION Only the misalignment for angle C heading can be measured independently As explained above the misalignments for angles B pitch and A roll are the resultant...

Page 9: ...8084 107 A6 Issue A Rev 6 Sonardyne International Limited 2013 9 Figure 2 Lodestar Mounting Angle Gamma Heading Example Figure 3 Lodestar Mounting Angle Beta Pitch Example Figure 4 Lodestar Mounting Angle Alpha Roll Example 1 1 Vessel view is bow on ...

Page 10: ... shown in Figure 5 the Lodestar is to be mounted horizontally on an ROV The Lodestar has been pitched forward 90 degrees to be mounted horizontally the X axis marking on the top of the Subsea Lodestar is now coincident with the Z axis of the vehicle s frame pointing in the down direction If no other rotations have been applied the resulting misalignment is 90 for misalignment angle B Figure 5 Exam...

Page 11: ...ar Heave Definition Remote Heave Some instruments on the vehicle may require heave compensation It is likely that few if any of these instruments are installed very close to the centre of the vehicle frame and so measurements of heave with respect to the vehicle CRP or the Lodestar may not be valid for those instruments If the Lodestar has information about the offset distances to a remote instrum...

Page 12: ...wing order 1 Offset distances X Y and Z 2 Misalignment Angles A B and C GPS Antenna The GPS antenna offset must be measured from the centre of the vehicle reference frame CRP to the phase centre of the antenna Settling Measurements of heading require the Lodestar firmware to identify the earth rotation which it uses to determine the true north direction This process does not happen instantaneously...

Page 13: ...onfiguration requirements The following items are required to help configure the Lodestar AHRS A computer with two serial ports running windows XP The Lodestar Hardware manual UM 8084 101 The Lodestar AHRS Messages Specification UM 8084 109 The Lodestar Configuration Software Lodestar test cables Configuration requirements The following information will be required to complete the installation of ...

Page 14: ...nts taken in the vessel s forward starboard and up frames with the distances measured from vehicle CRP to the GPS antenna A survey of the vehicle should generate accurate drawings of the vessel with reference points clearly visible If a survey has been scheduled for the near future it should include the Lodestar and the information concerning the Lodestar s location in the vessel should be made av...

Page 15: ...of installing either a surface or a subsea version of the Lodestar AHRS on board a vessel Surface Lodestar Figure 7 shows an example of a typical installation for the surface Lodestar Figure 7 Typical Installation of the surface Lodestar In the example shown Console Port is the command port and has its output communication parameters fixed on 9600 8 N 1 This port is connected to a PC running the L...

Page 16: ...00 8 N 1 This port is connected to a PC running the Lodestar Configuration Software C1 Port is the primary output port on the Subsea variant This port is connected to the navigation system T1 Port can be connected to a GPS receiver if possible for example when using the system with a multi beam or USBL when the Subsea Lodestar is not at depth T2 is another output port RS232 or RS485 and is not use...

Page 17: ...m its installed location after measuring the mounting angles and offsets If removed or disturbed then the misalignment is void Connect all the cables to be used for the installation Note the Console cable is different from the communications and transceiver cables Do not mix these cables The cables are keyed differently and colour coded For Subsea and Surface units a Red cable is for the console p...

Page 18: ...or Ethernet ports Serial Port The software will default to COM 1 on the PC Ethernet Port The Lodestar default Ethernet properties are IP Address 192 168 179 50 Subnet Mask 255 255 255 0 Command port socket 4000 The software will default to these values if the Ethernet options is chosen Make sure the PC Ethernet port is configured correctly to allow communication with the Lodestar s default setting...

Page 19: ...th Lodestar see Figure 9 Figure 9 Configuration Software Main Window not connected Configure the connection to the Lodestar by pressing the Connect button The application will default to a serial connection on PC port COM 1 as shown in Figure 10 Figure 10 Lodestar Serial Connection Settings To configure an Ethernet or NSH connection press the IP button and the default Lodestar Ethernet connection ...

Page 20: ... receive commands see Lodestar Hardware Manual UM 8084 101 for more details Once the connection parameters match the physical connection between the Lodestar and the PC press the OK button A window will appear indicating communication status with the Lodestar Once connected the software will populate with the Lodestar configuration and the status indicator circle on the bottom left hand side of th...

Page 21: ... re boot Lodestar completely resetting it Audible Alarm This setting will either enable or disable the audible alarm installed in the Surface Lodestar Note the surface Lodestar will always emit an audible alarm if external power is lost even if this setting is disabled Note The Subsea Lodestar does not have an audible alarm installed See section 7 on page 39 of this manual for further details on L...

Page 22: ...GPS input fails then the Lodestar will revert back to using the default Latitude Make sure the default Latitude setting is kept up to date in case the GPS input fails or is not available The default Latitude can be set by entering the operating Latitude in the Manual Latitude Setting panel see Figure 13 After setting the Latitude the user must press the Apply button on the main application window ...

Page 23: ...RP to the GPS antenna and press apply to send the changes to Lodestar Finally click on the Display NMEA GPS Telegrams to show any GGA telegrams that are being correctly received and decoded Figure 14 Automatic GPS Compensation Panel Heave Filter If required the Heave output from the Lodestar can be configured for the anticipated surface wave period experienced by the vehicle This can be set on the...

Page 24: ...er will be prompted to reset the Lodestar AHRS algorithm and it will be several minutes before the Lodestar output is settled Figure 16 Mounting Angles and Offsets Panel All mounting angles can be reset to zero using the button available Remote Output Points Lodestar measurements may be required for vehicle sensors that are not located near to the vehicle CRP such as remote heave For the Lodestar ...

Page 25: ...3 25 Guidance on Offsets Further information on Lodestar offsets angles and frames can be found in section 3 on page 7 of this manual If a copy of the manual is not available the user can view a summary guidance page explaining the Lodestar angles and offsets by pressing the Guidance button on the Offsets tab ...

Page 26: ...arameters for the Lodestar serial output ports Serial port settings The settings for the port can be viewed or modified in the Port Settings Panel see Figure 18 Figure 18 Port Settings Panel The baud rate protocol parity data and stop bits can be configured by selecting the appropriate value from the drop down lists and pressing the Apply button on the main application window Note Several settings...

Page 27: ...on Select the required output message by selecting a message type from the dropdown list in the MSG column Select an output rate up to 100Hz by entering the required value in the Rate column If this message is to be output with respect to a remote point on the vehicle select the appropriate remote point already setup on the Offset tab from the list in the Remote Point column After selecting the Re...

Page 28: ...moved or modified The IP port settings can be viewed and modified on the Port Configuration panel see Figure 20 Figure 20 IP Port Configuration Panel The IP address and subnet mask can be modified by changing the value then pressing the Set button CAUTION If connected to the Lodestar via the Ethernet port and wish to change the IP address or subnet mask it is strongly recommended that after changi...

Page 29: ... press the Remove button Select the ethernet port from which this message will be output using the dropdown list in the Port column Then select the required output message by selecting a message type from the dropdown list in the MSG column Select an output rate up to 100Hz depending on other outputs on this port by entering the required value in the Rate column If this message is to be output wit...

Page 30: ...n be enabled or disabled using the Analogue Output check box The options available for output on each analogue pin are as follows Table 2 Analogue Port output options Option Purpose PITCH degrees bow up ROLL degrees starboard down YAW 180 180 degrees HDG Quadrature Phase Signal SIN COS HEAVE Heave metres VZ Velocity in the Navigation Frame m s The voltage scale for each pin can be set from 0 10 vo...

Page 31: ...n to the right of the time and date value When the value is correct press the Set button to update the Lodestar time and date ZDA Port If GPS input is available and a GPS receiver is not already supplying the necessary NMEA 0183 GPZDA sentences to the Lodestar make sure the input is connected now The GPZDA input can be configured in the ZDA Port panel see Figure 24 Select the Lodestar port the GPS...

Page 32: ...ed to input the PPS pulse to the Lodestar The PPS input pulse can be configured in the PPS Port panel see Figure 25 Figure 25 PPS Port panel The Trigger Edge setting specifies whether the timing pulse should be measured on the rising high or falling low of the input signal The ZDA Sequence specifies when the ZDA message arrives with respect to the PPS timing pulse After PPS should be selected if t...

Page 33: ...respect to the CRP of the vehicle see Figure 26 Figure 26 Dynamic Display Note If the output is incorrect check the following settings are correct Mounting angles and offsets Default Latitude or automatic GPS compensation The method for checking the automatic GPS compensation in detail is explained below GPS Compensation Checks While the Dynamic Display window is open navigate to the Terminal tab ...

Page 34: ...ans the Lodestar is receiving and decoding valid GPGGA and GPVTG telegrams successfully g or G means the Lodestar is receiving and decoding only valid GPGGA telegrams v or V means the Lodestar is receiving and decoding only valid GPVTG telegrams u or U means the Lodestar is not receiving or decoding any valid GPGGA and GPVTG telegrams Troubleshooting Try the following remedies if the GPS input fla...

Page 35: ... recommended that file transfers for all applications of Lodestar use the Lodestar Ethernet port 4000 or C1 port with the exception of a SPRINT configuration which uses Ethernet port 4001 For Lodestar Ethernet port connection use Lodestar Subsea Ethernet test cable 8084 138 04 For Lodestar C1 port connection use Lodestar Subsea C1 test cable 8084 137 04 Connect to the Lodestar as described in sect...

Page 36: ...ltiplex is disabled refer to figures 30 and 31 Apply changes and wait for progress bar to complete prior to navigation to a new tab Figure 30 Lodestar Ethernet Port 4000 Configuration Figure 31 Lodestar Ethernet Port 4001 Configuration Serial port configuration Connect to the Lodestar C1 port use Auto Detect if unsure of C1 settings refer to figure 32 Figure 32 Lodestar C1 Port Connection ...

Page 37: ...e to the C1 tab and set the baud rate to 115200 and disable multiplex refer to figure 33 Apply changes and wait for progress bar to complete prior to navigation to a new tab Figure 33 Lodestar C1 Port Configuration SD File Transfer Navigate to the file transfer tab and select the data destination file as shown in figure 34 Figure 34 SD files destination folder ...

Page 38: ...SD logfiles and folders are named as D serial number year month day with the logfiles named with the addition of hours mins secs Select the logfile s for retrieval and click upload to PC refer to figure 35 Figure 35 Logfile Upload A progress bar will displayed during the data upload and wait for the upload progress bar to complete refer to figure 36 Figure 36 Data upload progress bar After file tr...

Page 39: ...destar also sends an alarm message if the threshold is not exceeded anymore to be acknowledged and counter acknowledged in the same manner The alarm and acknowledgement formats are described in the Lodestar AHRS Messages UM 8084 109 specification Alarm States An alarm message will be generated by the Lodestar for the following events or states Shutdown Imminent Battery voltage low No external powe...

Page 40: ...gle between Xned and the projection of Xb into the horizontal plane XYned measured about Zned Heading is in the interval 0º 359 999º Yaw is in the interval 179 999º 180 000º Pitch Pitch is the angle between Xb and the horizontal plane XYned Pitch is positive when Xb is pointed above the horizontal plane Pitch angle lies in the interval 90º 90º Roll Roll is the angle between Yb and the horizontal p...

Page 41: ...se the following effects There will be a fixed error between the vessel s true heading and the heading reported by the Lodestar There will be an element of the vessel s rolling motion appearing on the Lodestar s pitch and heading output There will be an element of the vessel s pitching motion appearing on the Lodestar s roll and heading output The size of the error depends on the misalignment angl...

Page 42: ... also calculate the misalignment angles that apply to roll pitch and heading outputs from the Lodestar Note that this method calculates the misalignments and offsets between the Lodestar GPS antenna and transceiver independent of the vessel frame However it can be used to define the vessel frame This method involves deploying a reference acoustic beacon on the sea bed and making simultaneous obser...

Page 43: ...vessel its measurements can be compared with those of Lodestar either simultaneously or through time stamped log files The mounting angle corrections can be applied to the Lodestar so that the two sets of measurements coincide Figure 37 Port or shore based alignment The Total Stations laser survey system must take a series of measurements on two prisms mounted on the vessel s centre line at the bo...

Page 44: ... when performed in sheltered waters where there is a good quality differential GPS service available Figure 38 Heading alignment at sea By post processing data logged from both GPS systems and from the Lodestar the vessel s true heading can be estimated at specific times as determined by the GPS time stamp This comparison allows a good estimation of the error included in the heading measurements f...