Xsens MTi 1 Series, Руководство пользователя

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MTi 1-series User Manual
Xsens MTi User Manual Repository Datasheet
Copyright © 2021 Xsens Page 31
Unit (IMU), Vertical Reference Unit (VRU), Attitude and Heading Reference System (AHRS) and
GNSS aided Inertial Navigation System (GNSS/INS). It can output 3D orientation data (Euler
angles, rotation matrix or quaternions), orientation and velocity increments (∆q and ∆v),
position and velocity quantities and calibrated sensor data (acceleration, rate of turn, magnetic
field). Depending on the product, output options may be limited to sensor data and/or
unreferenced yaw.
The MTi 1-s module features a 3D accelerometer, a 3D gyroscope, a magnetometer, a high-
accuracy crystal and a low-power MCU. The MCU coordinates the timing and synchronization of
the various sensors, applies calibration models (e.g. temperature models) and runs the sensor
fusion algorithm. The MCU also generates output messages according to the proprietary XBus
communication protocol. The data output is fully configurable, so that the MTi 1-s limits the
load, and thus power consumption, on the user application processor.
MTi-1 IMU
The MTi-1 module is an IMU that outputs calibrated 3D rate of turn, 3D acceleration and 3D
magnetic field. The MTi-1 also outputs coning and sculling compensated orientation
increments and velocity increments (∆q and ∆v). Advantages over a gyroscope-accelerometer
combo-sensor are the inclusion of synchronized magnetic field data, on-board signal
processing and the easy-to-use synchronization and communication protocol. Moreover, the
testing and calibration over temperature performed by Xsens result in a robust and reliable
sensor module that can be integrated within a short time frame. The signal processing pipeline
and the suite of output options allow access to the highest possible accuracy at any output data
rate, limiting the load on the user application processor.
MTi-2 VRU
The MTi-2 is a 3D VRU. Its algorithm computes 3D orientation data with respect to a gravity
referenced frame: drift-free roll, pitch and unreferenced yaw. Although the yaw is unreferenced,
it is superior to gyroscope integration. In addition, it outputs calibrated sensor data: 3D
acceleration, 3D rate of turn and 3D magnetic field data. All modules of the MTi 1-series output
data generated by the strapdown integration algorithm (orientation and velocity increments - ∆q
and ∆v). The 3D acceleration is also available as so-called free acceleration, which has the
local-gravity subtracted. The drift in unreferenced heading can be limited using the #Active
Heading Stabilization feature.