Digital Sensor Offset Control to Prevent Signal Saturation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Digital sensors can saturate due to unforeseen external disturbances, causing the measured physical quantity to exceed the sensor's measurement range, leading to inaccurate readings.

Innovation Solution

A system that continuously applies first and second offsets to the analog and digital signals, respectively, using control means to maintain the signal within the measurable range, preventing saturation by centering the digital signal and optionally applying gains to adjust the signal range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a digital sensor is used to measure a physical quantity, then the sensor provides digital output signals, but the sensor can saturate when external disturbances cause the measured quantity to exceed the measurement range

Engineering Contradiction:
Improvemeasurement accuracyVSAvoidsensor saturation
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent implements a feedback control system that continuously monitors the digital output signal from the sensor and dynamically adjusts the offset applied to the analog signal. The control unit calculates the difference between the current digital signal and the central value of the converter's output range, then uses this feedback to adjust the offset, creating a closed-loop system that prevents saturation and maintains measurement accuracy under varying conditions.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent dynamically changes the offset parameter of the analog signal based on the digital output. By continuously adjusting the offset value according to the measured physical quantity and the current operating point, the system adapts to external disturbances and keeps the sensor operating within its linear measurement range, preventing saturation.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If offset is applied to the analog signal to center the measurement range, then the sensor operates optimally within its range, but additional control complexity is introduced

Engineering Contradiction:
Improveoperational stabilityVSAvoidcontrol system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control unit automatically determines the appropriate offset adjustment based on the digital output signal from the sensor itself. The system uses the sensor's own output to control the offset applied to its input signal, eliminating the need for external calibration equipment or complex manual adjustment mechanisms. The control unit self-regulates by continuously monitoring the digital signal and adjusting the offset accordingly.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If continuous offset adjustment is applied to prevent saturation, then measurement accuracy is maintained, but energy consumption increases

Engineering Contradiction:
Improvesignal accuracyVSAvoidcontrol energy consumption
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent implements continuous control of the offset based on the digital output signal, adjusting the offset periodically according to each new digital value obtained from the sensor. This periodic adjustment ensures the sensor remains centered in its measurement range without requiring constant high-energy operation, as the control is triggered by signal changes rather than running at maximum intensity continuously.

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP2494695B1System and method for controlling a digital sensor
Publication Date: 2018.11.21 MOVEA
  • EP2494695B1 patent drawingFigure 1~2
  • EP2494695B1 patent drawingFigure 3~4
  • EP2494695B1 patent drawingFigure 5

AI summary

The system for controlling a digital sensor (CN) for measuring a physical quantity (GP) is furnished with a transducer (TRD) delivering at output an analogue signal representative of said physical quantity (GP), means (MGD) for implementing gain and/or shift on the analogue output signal (SA1) from said transducer (TRD), and with an analogue/digital converter (CAN) at the output of the sensor (CN) for delivering a digital signal (SN1). The system comprises, furthermore: first means (MA1) for applying a first shift to said analogue signal of the physical quantity (GP), second means (MA2) for applying a second shift to said digital signal (SN1), and control means (CMD) for continuously controlling said first application means (MA1), on the basis of said digital signal (SN1), and for continuously controlling said second application means (MA2), on the basis of said digital signal (SN1) and/or of said first shift.