IMU Fault Detection Using Master-Slave Sensor Voting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for detecting malfunctions in inertial measurement units (IMUs) are inadequate for cost-effective automotive applications, as they either require redundant high-quality sensors, which are space-consuming and costly, or fail to accurately identify defective sensors, posing safety risks in safety-critical applications like automated driving.
Innovation Solution
A method using at least three IMUs, with one as a master and two as slaves, estimates error model parameters to detect malfunctions through 2-out-of-3 voting, ensuring reliable compensation and switching to functional slaves in case of master failure, utilizing Kalman filters or recursive least squares for parameter estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If redundant high-quality sensors are used to detect malfunctions, then reliability is improved, but device complexity and cost increase
Solution Approach 1:
The system segments the sensor array into a master sensor and multiple slave sensors, allowing independent evaluation of each sensor's performance. This segmentation enables malfunction detection by comparing slave sensor readings against the master sensor without requiring all sensors to be identical high-quality units, thus reducing overall system complexity while maintaining reliability.
Solution Approach 2:
The master sensor acts as an intermediary reference against which slave sensors are compared. By using the master sensor as a mediator, the system can detect malfunctions in slave sensors through their deviation from the master's readings, eliminating the need for redundant high-quality sensors and simplifying the overall sensor configuration.
2Measurement precision
If additional sensors are used for malfunction detection, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The system uses a minimal number of sensors (one master and multiple slaves) rather than comprehensive redundant arrays. This partial action approach provides sufficient measurement precision for malfunction detection by comparing slave sensor readings against the master, avoiding the complexity of more extensive sensor arrangements while maintaining adequate detection capability.
3Device complexity
If sensor malfunctions are not detected, then device complexity is reduced, but safety risks increase
Solution Approach 1:
The system implements continuous feedback by constantly comparing slave sensor readings against the master sensor. This feedback mechanism enables real-time malfunction detection without requiring complex additional hardware, as the comparison process itself provides the safety check needed to identify sensor failures and prevent their propagation into navigation errors.
Data Source
AI summary
A method for detecting malfunctions in inertial measurement units which are used in a vehicle to measure angular velocities and specific forces may have at least three inertial measurement units. Each inertial measurement unit may have a plurality of sensors, such as accelerometer and gyroscopic sensors. A first inertial measurement unit is used as a master inertial measurement unit. A second inertial measurement unit and a third inertial measurement unit, the capabilities of which can be lower than those of the first inertial measurement unit, are used as slave inertial measurement units. Measurements of the master inertial measurement unit are used as reference values to compensate measurements of the slave inertial measurement unit regarding estimation of error model parameters with respect to the master inertial measurement unit to detect a malfunction in one of the three sensor signals.