Tactical-grade embeddable IMU and attitude reference system with quad-redundant IMU architecture, next-generation vibration rejection, and no magnetic dependencies — designed for UAVs, legged robotics, and industrial platforms.
3DM-CX7-AR
The 3DM-CX7-AR is a tactical-grade embeddable attitude reference system (VRU) from MicroStrain by HBK. It delivers high-accuracy roll and pitch estimation without magnetic heading dependency, making it ideal for platforms operating in magnetically noisy or electrically challenging environments such as industrial machinery, legged robots, and motor-heavy UAV frames.
At its core, the CX7-AR features a quad-redundant IMU architecture. With four internal IMUs continuously monitored in parallel, the system automatically detects untrustworthy measurements from any individual IMU and deweights or excludes its readings in real time — providing a level of measurement integrity not available in single-IMU designs. Combined with next-generation shock and vibration robustness validated at up to 100x better attitude stability under repeated high-g conditions, the CX7-AR maintains reliable orientation where conventional IMUs degrade or fail.
Every unit is individually calibrated across the full -40°C to 85°C operating range and features MicroStrain's auto-adaptive Extended Kalman Filter for real-time error rejection.
Key specifications include an extended ±32 g accelerometer range, ±4,000°/s gyroscope range, adjustable output rates up to 1 kHz, and a compact 8.3 g OEM form factor measuring 38 mm x 24 mm. The 3DM-CX7-AR is NDAA compliant, ITAR free, ROS ready, and PX4 compatible. It is part of the MicroStrain C-Series inertial sensor family, backed by 80+ years of HBK measurement heritage.
| Document | Type | Language |
|---|---|---|
| MicroStrain - Product Data - 3DM CX7 AR | Data Sheets | English |
| 3DM-CX7-AR and 3DM-CX7-AHRS User Manual (Online) | User Manual | English |
Certificates and Approvals
| Document | Type | Language |
|---|---|---|
| 3DM-CV7 Declaration of Conformity (UK) | Declaration of Conformity | English |
| 3DM-CV7 Declaration of Conformity (EU) | Declaration of Conformity | English |
| Property | Value |
|---|---|
| Type | Inertial (IMU) |
| Performance Grade | Tactical Grade |
| Features | Accelerometer, Barometer, Gyroscope |
| Random Walk | Accel: 36 µg/√Hz, Gyro: 0.058º/√h |
| Bias Instability (Gyroscope) | 2.1 °/hr |
| Bias Instability (Accelerometer) | 8.5 μg |
| Communication Port Type | Samtec FTS-105 (2x5) |
| Communication Interface | TTL serial |
| Update Rate | 1 to 1000 Hz |
| Inputs/Outputs | 4xGPIO |
| Weight | 8.3 g |
| Weight | 0.29 oz |
| Size | 38 x 24 x 8.6 |
| Size | 1.5 x 0.94 x 0.34 |
| Power Consumption | 0.324 W |
| Input Voltage | 3.2 to 5.2 VDC |
| Minimum Operating Temperature | -40 °C |
| Maximum Operating Temperature | 85 °C |
| Minimum Operating Temperature | -40 °F |
| Maximum Operating Temperature | 185 °F |
| MTBF | 1953356 h |
| Sensing Range (Accelerometer) | 32 g |
| Sensing Range (Gyroscope) | 4000 °/s |
| Sensing Range (Magnetometer) | 8 Gauss |
| Sensing Range (Pressure) | 1260 mbar |
| Ingress Protection Rating | Not Rated |
| Housing Material | Aluminum |
| Software | InertialConnect, MSCL, ROS, SensorConnect |
| Mounting Style | Embeddable, Precision Alignment, Screw Down |
| Badge | NEW |
| Product Code | Description |
|---|---|
6212-3006
|
OEM CABLE KIT |
6212-3009
|
C-Series Development Kit, USB |
6212-3010
|
C-Series Development Kit, RS232 |
Access your sensor's comprehensive online user manual. Find detailed setup instructions, calibration procedures, troubleshooting guides, and technical specifications all in one convenient location.
InertialConnect is the latest software solution for MicroStrain inertial sensors. With InertialConnect, you can easily configure your sensors, adjust parameters, upgrade firmware, and deploy preconfigured parameter files. You can also verify sensor outputs with intuitive visualizations, including times eries data, position data, and statuses.
InertialConnect is compatible with both PC desktop and Linux operating systems, making it your go-to solution for precision and efficiency in inertial sensor management.
SensorConnect is the next generation in desktop sensing software.
From configuration of nodes and starting networks, to collecting and analyzing data in real-time, SensorConnect provides a modern, powerful experience with our Wireless, Inertial, and Displacement products.
Using our intelligent data collection and graphing algorithms, you are able to visualize massive amounts of data instantly, and then zoom in on points of interest just as fast.
Built in MathEngine functionality allows for both real-time and post-processed math, such as generating FFTs, averages, RMS, etc.
SensorCloud is a unique sensor data storage, visualization, and remote management platform that leverages powerful Cloud computing technologies to provide excellent data scalability, rapid visualization, and user programmable analysis.
MicroStrain sensors can instantly upload their data to SensorCloud via an ethernet-connected WSDA-2000. Once uploaded, your data is securely stored in the Cloud and can be accessed from anywhere, or downloaded for offline use.
Configurable alerts can be set to help notify you of real-time event in your data.
MathEngine allows you to perform analytics on your data, all in the Cloud. Pre-built functions are available for ease of use, while IPython Notebooks allow advanced users to write custom scripts to be run on their data once, or on a schedule.
The MicroStrain Communication Library (MSCL) is our open-sourced API that simplifies writing code to interact with our sensors. MIP SDK is a lightweight C/C++ library for interacting with MicroStrain G and C-series products via baremetal and resource constrained microcontrollers.
Both APIs are readily available and fully-documented on GitHub, featuring valuable tools such as full documentation, example code, and a quick start guide.
Robot Operating System (ROS) is an open-source, meta-operating system for your robot. It provides the services you would expect from an operating system, including hardware abstraction, low-level device control, implementation of commonly-used functionality, message-passing between processes, and package management. ROS can be used in building and simulating robotics applications, as well as unmanned ground vehicles and simultaneous localization and mapping (SLAM). MicroStrain has an open source License free (MIT License) series of drivers specifically designed and tested for ROS.
PX4 is an open source flight control software for drones and other unmanned vehicles. The project provides a flexible set of tools for drone developers to share technologies to create tailored solutions for drone applications. PX4 provides a standard to deliver drone hardware support and software stack, allowing an ecosystem to build and maintain hardware and software in a scalable way. PX4 is fully supported on MicroStrain’s 3DM-CV7 family of inertial sensors.
The 3DM-CX7-AR is a tactical-grade Attitude Reference (AR) sensor that combines a precision IMU with advanced sensor fusion algorithms to provide highly accurate roll, pitch, angular rate, and acceleration measurements. You may also see the acronym “VRU” for this class of sensor, which stands for Vertical Reference Unit.
Unlike an AHRS, the CX7-AR does not rely on a magnetometer for heading estimation, making it ideal for environments where magnetic interference is present or magnetic heading is not required. It is optimized for high-vibration applications and packaged in an ultra-compact 8.3-gram OEM form factor.
The 3DM-CX7-AR builds upon the proven 3DM-CV7-AR platform with several major enhancements, including:
These improvements enable the CX7-AR to maintain stable attitude estimates in conditions that can challenge conventional MEMS-based attitude sensors.
The 3DM-CX7-AR continuously compares measurements from multiple inertial sensing elements operating in parallel. This redundant architecture allows the sensor to identify abnormal measurements caused by shock, vibration, or transient disturbances and reject them before they affect the attitude solution.
The result is improved reliability, enhanced attitude stability, and superior performance in harsh operating conditions.
The 3DM-CX7-AR offers up to 100 times greater resistance to vibration-induced errors compared to previous-generation products. In practical applications, this means more stable roll and pitch measurements, reduced vibration rectification error, and reliable attitude estimation even on platforms exposed to severe mechanical vibration.
This improvement is particularly important for industrial AGVs, UAVs, mobile robotics, and legged robots.
Unlike AHRS systems that depend on magnetometers to determine heading, the 3DM-CX7-AR provides a robust attitude solution without requiring magnetic heading measurements. This makes it particularly suitable for applications operating near electric motors, power systems, steel structures, industrial equipment, or other sources of magnetic disturbance where magnetometer performance may be compromised.
The 3DM-CX7-AR combines a tactical-grade gyroscope, redundant IMUs, adaptive filtering, and expanded measurement ranges of ±32 g and ±4000°/s. These capabilities allow the sensor to maintain accurate attitude estimation during rapid acceleration, sudden impacts, high angular rates, and aggressive vehicle maneuvers without compromising performance
External clock synchronization allows the 3DM-CX7-AR to precisely align its measurements with cameras, LiDARs, GNSS receivers, and other vehicle sensors. Accurate timing improves sensor fusion performance, reduces synchronization errors, and enhances state estimation for autonomous systems and robotics applications.
The 3DM-CX7-AR is particularly well suited for:
Its vibration tolerance and reliable attitude estimation make it ideal for demanding dynamic environments.
The 3DM-CX7-AR features a tactical-grade gyroscope with a bias instability of 2.1°/hour. This low drift characteristic helps maintain long-term attitude stability, reduces accumulated orientation errors, and improves performance in stabilization, control, and navigation applications where precision attitude information is critical..
Yes. The 3DM-CX7-AR is NDAA compliant and ITAR free, making it suitable for a wide range of commercial, industrial, and government-related applications. It is also supported by the MicroStrain software ecosystem, including ROS drivers, PX4 integration, MSCL API, MIP SDK, SensorConnect™, and InertialConnect™ to simplify development and deployment.
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