Cnsens Technology
WS-602 High Performance Ocean Wave Motion Sensor
Technical manual REV D
Copyright Š Cnsens Technology Corporation (Owned by Cnsens Inc.)
WS-602 Manual
Table of Contents 1. INTRODUCTION......................................................................................................................................................... 1 1.0. GENERAL DESCRIPTION ................................................................................................................................... 1 1.1. HOUSING STYLE ................................................................................................................................................. 1 1.2. ORIENTATION ...................................................................................................................................................... 2 2. SPECIFICATIONS ...................................................................................................................................................... 3 3. CONNECTIONS AND INSTALLATION.................................................................................................................... 4 3.1. ELECTRICAL CONNECTIONS ........................................................................................................................... 4 3.2. INSTALLATION RECOMMENDATIONS ........................................................................................................... 4 4. COMMANDS AND DATA FORMATS ....................................................................................................................... 5 4.0. INTRODUCTION .................................................................................................................................................. 5 4.1. WS-602 COMMAND SET ..................................................................................................................................... 5 4.2. HEADER AND STATUS BYTES .......................................................................................................................... 5 4.3. WS-602 Command Set Details ............................................................................................................................... 6 4.3.1. Attitude Output .......................................................................................................................................... 6 4.3.2. Sensor Output ........................................................................................................................................... 6 4.3.3. Attitude (with Heave and Sensor) Output (Default) ............................................................................. 7 5. Ordering code ............................................................................................................................................................ 10
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WS-602 Manual
1. INTRODUCTION
1.0. GENERAL DESCRIPTION The WS-602 uses extremely high performance, best-in-class MEMS accelerometers and angular rate gyroscopes to measure attitude and heave of a vessel at sea. The WS-602’s triad of accelerometers measure accelerations in the range of ± 2g, and the triad of gyroscopes measure rotational rates in the range of ±100º/sec. Data fusion of accelerometer and gyroscope data is performed by wave-model driven Kalman Filter and heave integrator implemented on the built-in Digital Signal Processor. The result of the filter is to complement the short-term accuracy of the gyros with the long-term stability of the accelerometers to achieve the optimal estimation of the dynamic roll and pitch angles, and bounds the vertical position drift error to minimal to obtain the accurate heave and vertical velocity. The WS-602 is calibrated over working temperature with aero grade rate table to guarantee accuracy and performance under challenging environment. In addition, the WS-602 can optionally accept external GPS NMEA or Honeywell HMR3000 code to regulate the heading and improve the accuracy. Related hardware and firmware is available upon request. The WS-602 uses serial port to communicate: •
Port 1:
Data and Configuration Port (RS232)
The Port 1 allows the user to select various options such as baud rate, pitch and roll axis swap etc. It has a maximum output rate of 250Hz depending on the selected baud rate.
1.1. HOUSING STYLE The WS-602 contains a complete mechanically calibrated unit inside its anodized aluminum housing. The housing has 6 mounting holes plus 2 positioning holes machined into the base that can be used to attach to any flat surface. The unit has a waterproof circular connector, which is used to connect to external power supply and signal wires. The WS-602 housing is precisely machined to provide a high quality and extremely rugged case with 5052 solid aluminum. Hard anodizing to the housing gives protection from corrosion in the sea environment. 1
WS-602 Manual
Figure 1.1: WS-602 Housing 1.2. ORIENTATION The WS-602 unit orientation is shown in Figure 1.2, where x is the pitch axis (towards front of the vessel), y is the roll axis and z is the heave axis.
Fig. 1.2: WS-602 Installation orientation
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WS-602 Manual 2. SPECIFICATIONS Table 2.1 shows the initial specification for the WS-602 unit. Specifications Update Rate 100 Fully Stabilized Data 120 Attitude ±20 • Range: Heave 5cm or 5% whichever is greater • Dynamic accuracy <1 • Resolution ±180, ±90 • Range: Roll, Pitch 0.05 • Static accuracy 0.1 • Dynamic accuracy <0.01 • Resolution Angular Rate ±100 • Range: Roll, Pitch, Yaw <±0.03 • Bias error: Roll, Pitch <0.5 • Scale factor accuracy 0.1 • Non-linearity <0.025 • Resolution 40 • Bandwidth 0.2 • Random walk Acceleration ±2 • Range: X/Y/Z ±0.5 • Bias: X/Y/Z <0.2 • Scale factor accuracy 0.1 • Non-linearity <0.1 • Resolution 5 • Bandwidth 3 • Random walk Environment -20 to 85 • Operating temperature -55 to 125 • Storage temperature 2 (any axis) • Operating vibrations 200 • Non-operating shock Electrical 12±1 • Supply Voltage 3.5 • Power Consumption 8 • MAX ESD Discharge • Communication interface RS232 Table 2.1: Specification
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Units Hz s m cm ° ° rms ° rms ° °/sec °/sec % % FS °/sec Hz °/√hr Typ. g mg % % FS mg Hz m/s/√hr °C °C g g (0.1ms) V W kV
WS-602 Manual 3. CONNECTIONS AND INSTALLATION
3.1. ELECTRICAL CONNECTIONS The WS-602 comes with an IP67 waterproof circular connector. This connector has the numbering shown in table 3.1. Wire No. 1 2 3 4 5 6 7
Function Positive power supply, 12V Typical Power ground Data transmit Data receive Heart beat Signal ground Case: Protection earth
Table 3.1: Connector definition 3.2. INSTALLATION RECOMMENDATIONS The WS-602 measures motion of a vessel. Hence care must be taken in installation to have best accuracy. 1. The WS-602 must be installed wi th screws to have best accuracy and avoid relative motion to the reference surface during operation. 2. Place the WS-602 as close to th e required position (such as a depth sensor) or the center of gravity of the vessel (in the case of vessel monitoring) as possible. 3. Align the axis of the WS-602 to the vessel or reference precisely. If misalignment error can be measured, it can be adjusted by PC software. 4. Avoid severe vibration and temperature variation. 5. Avoid shock and dropping. Excessive shock over the specification may temporarily or permanently damages the sensors. 6. Always power up the unit with stable and clean power supply. Use an external regulator if necessary.
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WS-602 Manual
4. COMMANDS AND DATA FORMATS
4.0. INTRODUCTION The WS-602 has a serial port, Port 1. Port 1 sends the attitude and sensor information in binary format, and also accepts configuration commands or GPS/Compass data. Port 1 100 packets/s 38400bps 8-N-1
Update Rate Baud Rate Modes
Table 4.1: Serial ports properties 4.1. WS-602 COMMAND SET There are 3 user commands in the Command Set. 1. Attitude Output 2. Sensor Output 3. Attitude (with Heave and Sensor) Output (Default) Device settings are provided using the PC software, thus are omitted from this manual. 4.2. HEADER AND STATUS BYTES Each data packet starts with 2 header bytes (0xBD and 0xDB) and 1 status byte. The status byte bit format: Bit No. 7 6 5 4 3 2 1 0
Content Sensor Error
Description 0000: No sensor error detected. 0001 to 1111: Sensor error detected.
EEPROM Error When this bit is set, an internal EEPROM checksum error has been detected. Bits 0 to 2 indicate the type of output data Output Type 000: Attitude Output 001: Sensor Output 100: Attitude (with Heave and Sensor) Output Other bit combinations are reserved for factory use. 5
WS-602 Manual Table 4.2: Status byte description 4.3. WS-602 Command Set Details 4.3.1. Attitude Output Command format: Byte No. Content Description 1 0xBD First header byte 2 0xDB Second header byte 3 0x55 Attitude Output command byte 4 0x33 Checksum: Byte-wise XOR of byte 1 to 3. Table 4.3: Attitude Output command format Upon receiving this command, the WS-602 initializes its internal filter and attitude estimation states and outputs attitude (roll, pitch and yaw) data. Data is output continuously at a rate of 100 packets per second. Note: Upon power-up, the WS-602 outputs Attitude Output by default. Attitude Output data packet format: Byte No. Content Description 1 0xBD First header byte 2 0xDB Second header byte 3 Status Status byte 4 LSB of Roll Roll 5 MSB of Roll 6 LSB of Pitch Pitch 7 MSB of Pitch 8 LSB of Yaw Yaw 9 MSB of Yaw 10 Checksum Byte-wise XOR of byte 1 to 9 Table 4.4: Attitude Output data packet format Roll, Pitch and Yaw are output as scaled 16-bit signed integers. To scale into degrees, multiply Roll, Pitch or Yaw by this factor: 360/215. 4.3.2. Sensor Output Command format: Byte No. Content 1 0xBD 2 0xDB 3 0x58 4 0x3E
Description First header byte Second header byte Sensor Output command byte Checksum: Byte-wise XOR of byte 1 to 3. 6
WS-602 Manual Table 4.5: Sensor Output command format Upon receiving this command, the WS-602 outputs its filtered and fully compensated sensor data. Data is output continuously at a rate of 100 packets per second. Sensor output data packet format: Byte No. Content Description 1 0xBD First header byte 2 0xDB Second header byte 3 Status Status byte 4 LSB of x-axis gyroscope GX 5 MSB of x-axis gyroscope 6 LSB of y-axis gyroscope GY 7 MSB of y-axis gyroscope 8 LSB of z-axis gyroscope GZ 9 MSB of z-axis gyroscope 10 LSB of x-axis accelerometer AX 11 MSB of x-axis accelerometer 12 LSB of y-axis accelerometer AY 13 MSB of y-axis accelerometer 14 LSB of z-axis accelerometer AZ 15 MSB of z-axis accelerometer 16 Checksum Byte-wise XOR of byte 1 to 15 Table 4.6: Sensor Output data packet format All sensor data are output as scaled 16-bit signed integers. To scale into degrees per second, multiply GX, GY or GZ by this factor: 150/215. To scale into g, multiply AX, AY or AZ by this factor: 2/215. 4.3.3. Attitude (with Heave and Sensor) Output (Default) Command format: Byte No. Content 1 0xBD 2 0xDB 3 0x65 4
Description First header byte Second header byte Attitude (with Heave and Sensor) Output command byte 0x03 Checksum: Byte-wise XOR of byte 1 to 3. Table 4.7: Attitude (with Heave and Sensor) Output command format
Upon receiving this command, the WS-602 initializes its internal filter and attitude estimation states and outputs attitude (roll, pitch and yaw) and heave (vertical velocity and position) data. In addition, each data output packet also includes the fully 7
WS-602 Manual compensated sensor (3-axis gyro and 3-axis accelerometer) data. Data is output continuously at a rate of 100 packets per second. Note: After receiving this command, the WS-602 requires about 120 seconds for its heave filters to stabilize. During this time, the vertical velocity and vertical position outputs are not valid. Attitude (with heave and sensor) output data packet format: Byte No. Content Description 1 0xBD First header byte 2 0xDB Second header byte 3 Status Status byte 4 LSB of Roll Roll 5 MSB of Roll 6 LSB of Pitch Pitch 7 MSB of Pitch 8 LSB of Yaw Yaw 9 MSB of Yaw 10 Vertical Velocity LSB of Vertical Velocity 11 MSB of Vertical Velocity 12 Vertical Position LSB of Vertical Position 13 MSB of Vertical Position 14 GX LSB of x-axis gyroscope 15 MSB of x-axis gyroscope 16 GY LSB of y-axis gyroscope 17 MSB of y-axis gyroscope 18 GZ LSB of z-axis gyroscope 19 MSB of z-axis gyroscope 20 AX LSB of x-axis accelerometer 21 MSB of x-axis accelerometer 22 AY LSB of y-axis accelerometer 23 MSB of y-axis accelerometer 24 AZ LSB of z-axis accelerometer 25 MSB of z-axis accelerometer 26 Temperature LSB of sensor temperature T 27 MSB of sensor temperature 28 Time Stamp Byte 1 of time stamp (LSB) TS 29 Byte 2 of time stamp (Unsigned 30 Byte 3 of time stamp integer) 31 Byte 4 of time stamp (MSB) 32 Checksum Byte-wise XOR of byte 1 to 31 Table 4.8: Attitude (with Heave and Sensor) Output data packet format Roll, Pitch and Yaw are output as scaled 16-bit signed integers. Vertical Velocity and Vertical Position are output as scaled 16-bit signed integers. All sensor data are output as scaled 16-bit signed integers. 8
WS-602 Manual To scale into degrees, multiply Roll, Pitch or Yaw by this factor: 360/215. To scale into meters per second, multiply Vertical Velocity by this factor: 10/215. To scale into meters, multiply Vertical Position by this factor: 20/215. To scale into degrees per second, multiply GX, GY or GZ by this factor: 150/215. To scale into g, multiply AX, AY or AZ by this factor: 2/215. To scale into degree Celsius, multiply T by this factor: 200/215. The unit of time stamp is 0.01s (the time from power on of the unit).
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WS-602 Manual 5. Ordering code Model Number: WS-602PKG which includes: Wave Sense Senor: WS-602 Rev. A Plug and cable: WS-602CA Software: Wave Sense Viewer Manual: WS-602HWMN (This manual) WS-602SWMN (Software manual) Extensions: Navigation adapter: WS-602NA (for connecting compass and GPS) Compass module: HMR3000 from Honeywell GPS module: WS-602EGPS
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WS-602Manual Mechanical Drawings
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