Sensor Blending with Offset Adjustment for Wide-Range IMU
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current low-cost sensors, such as MEMS-based IMUs, often have limited operational ranges and performance, failing to provide high performance over a wide range of rates and accelerations, which is essential for applications like UAVs, missiles, and other dynamic systems.
Innovation Solution
A method that combines the outputs of two sensors with overlapping operational ranges using a blending function and real-time bias estimation and compensation, allowing seamless transitions between low and high acceleration ranges without the need for factory calibration of both sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If low-cost sensors are used, then manufacturing cost is reduced, but operational range and performance are limited
Solution Approach 1:
The patent combines outputs from multiple low-cost sensors with different operational ranges using a blending function. This merging approach allows the system to achieve an extended operational range that exceeds what any single low-cost sensor can provide, while maintaining cost-effectiveness by using multiple affordable sensors rather than one expensive high-range sensor.
Solution Approach 2:
The patent creates a composite sensor system by integrating multiple sensor outputs with different characteristics. By combining sensors with overlapping but distinct operational ranges and applying bias compensation, the system achieves performance characteristics similar to expensive single-sensor solutions while maintaining low-cost construction.
2Adaptability or versatility
If multiple sensors are combined to extend operational range, then measurement capability is improved, but sensor bias and offset errors increase
Solution Approach 1:
The patent implements real-time bias estimation and compensation by continuously monitoring sensor outputs and adjusting for offset errors. The system estimates bias dynamically and applies corrections to the blended output, ensuring measurement precision is maintained across the extended operational range despite combining multiple sensors with inherent biases.
Solution Approach 2:
The patent changes the operational parameters of the sensor system by dynamically adjusting bias compensation values based on the current operational range and sensor inputs. This allows the system to optimize measurement precision across different acceleration and rate conditions while maintaining the extended operational range benefits of multiple sensors.
3Measurement precision
If factory calibration is performed on both sensors, then measurement accuracy is improved, but manufacturing time and cost increase
Solution Approach 1:
The patent enables the sensor system to perform self-calibration by estimating bias through real-time processing of sensor outputs during normal operation. This eliminates the need for time-consuming factory calibration of both sensors, as the system automatically compensates for biases using its own operational data, thereby reducing manufacturing time while maintaining accuracy.
Solution Approach 2:
The patent performs preliminary bias estimation during the manufacturing process for one sensor, then uses real-time bias compensation algorithms to handle the second sensor during operation. This preliminary action reduces the calibration burden during manufacturing while ensuring overall system accuracy through ongoing computational compensation.
Data Source
AI summary
A method for generating a sensor output from the outputs of first and second sensors is provided. The method comprising receiving the outputs from the first and second sensors; estimating an offset between the outputs of the first and second sensors over a first range of outputs; adjusting the output of the second sensor based on the estimated offset; and generating a sensor output, based on the output of the first sensor, the adjusted output of the second sensor and a blending function that blends the output of the first sensor and the adjusted output of the second sensor.