Actuator Noise Reduction via Feedback Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Fuel pumps in internal combustion engines produce significant noise due to piston impacts against limit stop organs, which existing control methods fail to effectively reduce, especially at low engine speeds, and lack diagnostic capabilities for actuator device faults.

Innovation Solution

A method to control an electromechanical linear actuator device using sensors to detect noise signals, processing them with band-pass filtering or Fourier transforms to calculate a noise index, adjusting actuation profiles to minimize noise and diagnose potential faults by comparing the index with reference values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If software control is used to adjust the intensity and waveform of control current to minimize piston kinetic energy at impact, then noise is reduced, but the control system becomes ineffective due to open-loop operation and variability of limit current values

Engineering Contradiction:
ImprovenoiseVSAvoidcontrol effectiveness
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent implements feedback by using a sensor to detect the actual position of the piston and feeding this information back to the control system. This allows the control system to adjust the control current in real-time based on the actual piston position, ensuring reliable closed-loop control while effectively minimizing impact noise through precise timing of the control current waveform.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies preliminary action by pre-calculating and storing optimal control current waveforms that minimize piston impact kinetic energy. These pre-computed control strategies are then selected and applied based on operating conditions, allowing the system to achieve effective noise reduction without requiring complex real-time calculations while maintaining reliable closed-loop control through feedback.

Inventive Principle:
Principle #10Preliminary action

2Measurement precision

If additional sensors and computational resources are used to improve noise detection and fault diagnosis capabilities, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvenoise detection capabilityVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies universality by designing a control system that uses the existing sensor primarily for noise detection and fault diagnosis, while also utilizing it for basic position control feedback. The same computational resources used for engine management are leveraged to process the sensor signals for noise analysis, eliminating the need for dedicated additional components and achieving multi-functionality without increasing device complexity.

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

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Effectively reduces noise generated during both intake and delivery strokes and enables fault diagnosis of the actuator device without requiring additional components or excessive computational resources.

Implementation Method 1

using sensors to detect noise signals

Methodology Applied
Scientific EffectAcoustic wave propagation: Sound

Implementation Method 2

processing them with band-pass filtering

Methodology Applied
Scientific EffectBand-pass filtering: Filter (electronic)

Implementation Method 3

Fourier transforms to calculate a noise index

Methodology Applied
Scientific EffectFourier transform:

Implementation Method 4

electromagnetic actuator, which is designed to move the piston

Methodology Applied
Scientific EffectElectromagnetic actuation: Electromagnet

Data Source

PatentEP3404241B1Method to control an electromechanical linear actuator device for an internal combustion engine
Publication Date: 2021.10.06 FAB ITAL MAGNETI MARELLI SPA
  • EP3404241B1 patent drawingFigure 1
  • EP3404241B1 patent drawingFigure 2
  • EP3404241B1 patent drawingFigure 3~4

AI summary

A method is described to control an actuation profile of an electromechanical linear actuator device (20) of an internal combustion engine (ICE) designed to control the movement of a component (14, 27); the internal combustion engine (ICE) comprises a sensor (31), which faces the actuator device (20) and is designed to detect the noise generated by the movement of the component (14, 27); the method comprises the steps of acquiring, by means of the sensor (31), the intensity of a signal (S) generated by the impact of the component (14, 27) against a limit stop; identifying a first listening window (OW; CWi) of the signal (S) associated with said impact; calculating a noise index (IDRC; IDRCi) inside the listening window (OW; CWi); comparing the noise index (IDRC; IDRCi) with a reference value (IDRR); and controlling the actuation profile of the actuator device (20) based on this comparison.