Project | Content | Index | Notes |
Performance indicators of gyroscope |
Zero bias indicator | Zero bias stability (100s) | 0.005°/h | |
Zero bias stability (10s) | 0.01°/h | |
Variable temperature zero bias stability | 0.02°/h | |
Scale Factor | Full temperature scale factor | ≤150ppm | |
Other indicators | Random walk coefficient | 0.001°/√h | |
Input range | 400°/s | |
Performance indicators of accelerometer |
Deviation index | Deviation monthly comprehensive error | 20μg | |
Zero bias indicator | Zero bias temperature sensitivity | 20μg/℃ | |
Scale Factor | Scale factor monthly comprehensive error | 20ppm | |
Scale factor temperature sensitivity | 20ppm/℃ | |
Range indicator | Input range | ±20g | |
Whole machine characteristics |
Environmental performance indicators | Operation temperature | -40℃～60℃ | |
Storage temperature | -45℃～70℃ | |
General requirements | Power supply | 18～36V(DC) | |
Stable power consumption | ≤15W | Startup power consumption ≤ 25W |
Communication protocols
This article is a communication protocol for recording data in the
universal debugging interface of aerospace unified software. The
baud rate of the debugging data output by the software is 460800,
with 8 data bits and 1 stop bit, no checksum, and sent in low to
high order. General debugging data includes IMU raw data, user
command data, satellite navigation record data, navigation result
data, etc. The specific agreement is as follows.
SN | Message content | Type | Notes |
1~2 | frame header | char | 0x5A,0x54 |
3 | frame length | char | 0x1E |
4 | Frame ID | char | 0x04 |
5~8 | Frame Number | int | 200Hz accumulation |
9~11 | X accelerometer output | char×3 | Note 1 |
12~14 | Y accelerometer output | char×3 |
15~17 | Z accelerometer output | char×3 |
18~20 | X gyroscope output | char×3 | Note 2 |
21~23 | Y gyroscope output | char×3 |
24~26 | Z-gyroscope output | char×3 |
27 | reserve | char | |
28~31 | reserve | int | |
32~33 | reserve | short | 0x5A,0x54 |
34 | checksum | | Total of 4-33 bytes |
Note 1: Calculation method for speed increment
(1) The 5ms velocity increment value output by the accelerometer at
time tk is yk (unit: m/s);
(2) Define the initial value of speed increment accumulation
SumVelInt=0;
(3) Define Yk=int [yk × 1e5+δ Yk-1], where int [·] represents
rounding operation, and δ Yk-1 represents the remainder after
rounding the velocity increment in the previous step;
(4) The remainder after rounding Yk: δ Yk=yk × 1e5+δ Yk-1-Yk;
(5)SumVelInt = SumVelInt + Yk；
(6) Integer range limitation for SumVelInt:
If SumVelInt ≥ 1e7, SumVelInt=SumVelInt -1e7;
If SumVelInt<0, SumVelInt=SumVelInt+1e7;
After integer processing, limit the range of SumVelInt values to
[0,1e7);
(7) Send the last 3 bytes of SumVelInt after integer processing.
Note 2: Calculation method for angle increment
(1) The 5ms angular increment value of the gyroscope output at time
tk is xk (unit: rad);
(2) Define the initial value SumAngInt for angle increment
accumulation as 0;
(3) Define Xk=int [xk × 1e7+δ Xk-1], where int [·] represents the
rounding operation, and δ Xk-1 represents the remainder after
rounding the previous angular increment;
(4) The remainder after rounding Xk: δ Xk=xk × 1e7+δ Xk-1-Xk;
(5)SumAngInt = SumAngInt + Xk；
(6) The integer range limitation of SumAngInt:
If SumAngInt ≥ 1e7, SumAngInt=SumAngInt -1e7;
If SumAngInt<0, SumAngInt=SumAngInt+1e7;
After integer processing, limit the range of SumAngInt values to
[0,1e7);
(7) Send the last 3 bytes of SumAngInt after integer processing.
Electrical interfaces
The external electrical interfaces of the inertial group equipment
include power interface RS422 communication interface and 100Mbps
Ethernet interface. The socket model for the external electrical
interface is J30JM-37ZKP, and the matching plug model is
J30J-37TJL.
Pin | Connectivity | Signal name | Signal characteristics |
1,2 | External power supply | PCS power supply positive | 24V |
3,4 | PCS power supply ground | Power Ground |
5 | 200Hz signal output | IMU_TX1+ | IMU data output positive |
6 | IMU_TX1- | IMU data output negative |
9 | Synchronization signal | IMU_SYN+ | IMU synchronization signal positive |
10 | IMU_SYN- | IMU synchronization signal negative |
Dimensions
Dimensions: 158mm × 161mm × 122.5mm (± 1mm, excluding connectors)
Installation size: 146mm × 149mm, installation aperture: 4- Φ 5.5mm
Weight: ≤ 3.6kg
