Linear Acceleration Sensor Array for 3D Position Tracking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the position, speed, and acceleration of a body in three-dimensional space using linear acceleration sensors are complex, expensive, and imprecise due to manufacturing and positioning tolerances, leading to significant errors in angular acceleration calculations.

Innovation Solution

A method and device utilizing at least twelve linear acceleration sensors with direction vectors aligned to form a twelve-column matrix, allowing for precise determination of position, speed, and acceleration by forming a position, speed, and/or acceleration signal from acceleration measurement signals and parameters describing the sensors' orientation in a body-fixed coordinate system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a large number of linear acceleration sensors (nine cardial sensors) are arranged at multiple positions to measure acceleration measurement signals, then the completeness of acceleration data is improved, but the device complexity and cost increase significantly

Engineering Contradiction:
Improvecompleteness of acceleration dataVSAvoiddevice complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts only the essential acceleration measurement components needed for position determination. Instead of using nine cardial acceleration sensors, it employs a reduced set of linear acceleration sensors (minimum three) arranged in a simplified configuration, removing redundant sensing elements while maintaining measurement capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent segments the acceleration measurement function into essential and non-essential components. By dividing the measurement task and identifying only the critical acceleration components needed for position calculation, the system achieves accurate position determination with fewer sensors.

Inventive Principle:
Principle #1Segmentation

2Ease of operation

If linear acceleration sensors are arranged in a right-angled configuration to simplify calculations, then the ease of calculation is improved, but manufacturing and positioning tolerances cause significant errors in angular acceleration calculations

Engineering Contradiction:
Improveease of calculationVSAvoidaccuracy of angular acceleration calculations
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent performs preliminary calibration to determine the actual position and orientation parameters of the linear acceleration sensors before use. By pre-measuring and storing the deviation parameters from ideal right-angled positions, the system compensates for manufacturing tolerances during the calculation phase, maintaining accuracy without requiring perfect mechanical alignment.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent transforms the calculation approach by incorporating actual sensor position and orientation parameters (deviating from ideal right-angled positions) into the calculation formulas. Instead of assuming perfect geometric relationships, the system uses measured parameters to adjust the calculation model, thereby compensating for manufacturing tolerances.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If only four linear acceleration sensors are used to measure angular acceleration, then the device complexity is reduced, but the measurement precision and reliability of position determination deteriorate

Engineering Contradiction:
Improvedevice complexityVSAvoidmeasurement precision
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent designs the linear acceleration sensor arrangement to serve multiple functions simultaneously. The same sensor configuration used for measuring linear acceleration also provides the necessary data for determining angular acceleration and position, eliminating the need for separate sensing systems and achieving multi-functional measurement with minimal sensors.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent extends the measurement capability by utilizing the temporal dimension and mathematical processing. By sampling acceleration data over time and applying integration algorithms, the system extracts position and orientation information from linear acceleration measurements, effectively adding dimensional information through signal processing rather than additional physical sensors.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP1889006B1Method and device for determining the relative position, speed and/or acceleration of a body
Publication Date: 2013.09.25 ALBERT LUDWIGS UNIV FREIBURG
  • EP1889006B1 patent drawingFigure 1a
  • EP1889006B1 patent drawingFigure 1b
  • EP1889006B1 patent drawingFigure 1c

AI summary

The invention relates to method for determining the relative position, speed and/or acceleration of a body that can be displaced in a three-dimensional space. According to the invention, at least twelve linear acceleration sensors are disposed in respective positions that are stationary in relation to the body. These linear acceleration sensors detect at least one acceleration measuring signal. The acceleration measuring signal and variables that are characteristic of the position and orientation (3) of the linear acceleration sensors in the body-fixed system of coordinates are used to produce a position, speed and/or acceleration signal for the body.