MEMS Lidar Beam Steering for Multi-Axis Wind Turbine Velocity Measurement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional LIDAR systems with a single telescope are limited to line-of-sight measurements, and solutions involving multiple telescopes or beam switching face challenges such as misalignment, optical power loss, and sensitivity to environmental conditions, making them cumbersome and difficult to align, especially when installed on structures like wind turbines.

Innovation Solution

A LIDAR system incorporating a micro-electro-mechanical-system (MEMS) with a reflecting element that can be positioned to align the output beam with the optical axes of multiple beam-focusing optical units, allowing for easy and precise alignment without mechanical adjustments, and capable of directing the beam between units to maintain optimal alignment despite misalignments or environmental changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple telescopes are used to measure multiple velocity components, then measurement capability is improved, but device complexity and alignment difficulty increase

Engineering Contradiction:
Improvemeasurement capabilityVSAvoiddevice complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The system divides the measurement function into multiple beam-focusing optical units, each capable of measuring velocity components in different directions. This segmentation allows the system to measure multiple velocity components while maintaining a relatively simple overall structure compared to using multiple complete telescopes.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A single telescope is designed to perform multiple functions by incorporating multiple beam-focusing optical units that can be selectively activated. This multi-functionality approach allows one telescope to replace what would traditionally require multiple separate telescopes, reducing device complexity while maintaining measurement capability.

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

2Adaptability or versatility

If beam switching between multiple optical units is implemented, then measurement versatility is improved, but alignment precision deteriorates due to sensitivity to misalignment

Engineering Contradiction:
Improvemeasurement versatilityVSAvoidalignment precision
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The system employs a dynamic alignment approach where the beam direction is actively adjusted using a scanning unit to compensate for misalignments between the light source and beam-focusing optical units. This dynamic compensation maintains alignment precision despite manufacturing tolerances and environmental changes.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system incorporates feedback mechanisms that monitor the alignment between the light beam and optical units, and automatically adjust the beam direction or optical unit positioning to maintain optimal alignment. This feedback loop compensates for misalignments caused by manufacturing variations and environmental factors.

Inventive Principle:
Principle #23Feedback

3Loss of energy

If fiber optics are used for beam switching, then optical power loss is reduced, but alignment complexity increases

Engineering Contradiction:
Improveoptical power lossVSAvoidalignment complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The system replaces mechanical beam switching mechanisms with optical fiber-based beam delivery. The fiber optics guide the light beam from the source to the beam-focusing optical units, eliminating the need for complex mechanical moving parts while maintaining efficient light transmission with minimal power loss.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Device complexity

If a single telescope is used for line-of-sight measurement, then device complexity is reduced, but measurement versatility deteriorates

Engineering Contradiction:
Improvedevice complexityVSAvoidmeasurement versatility
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The system extends the measurement capability from single-dimensional line-of-sight measurement to multi-dimensional velocity component measurement by incorporating multiple beam-focusing optical units with different viewing angles. This dimensional extension allows a single telescope to measure velocity components in multiple directions simultaneously.

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

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

The MEMS-based LIDAR system enables efficient, accurate, and stable alignment with minimal optical loss, resistance to wavelength and environmental variations, and the ability to tune focusing distance, providing a simple and reliable method for measuring multiple velocity components without the need for fiber alignment, thus extending system lifetime and reducing installation complexity.

Implementation Method 1

a beam-steering element in optical connection with the beam generating section and comprising a micro-electro-mechanical-system (MEMS) comprising at least one reflecting element adapted to be arranged in a plurality of positions, the beam-steering element configured such that the output beam can be directed interchangeably between the at least one optical element for each of the beam-focusing optical units by selectively positioning the reflecting element(s)

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP3234642B1Lidar based on MEMS
Publication Date: 2020.02.19 WINDAR PHOTONICS
  • EP3234642B1 patent drawingFigure 1
  • EP3234642B1 patent drawingFigure 2
  • EP3234642B1 patent drawingFigure 3

AI summary

The present invention relates to a system for measuring velocity of particles such as particles in air. The present invention relates in particular to a Light Detection and Ranging (LIDAR) system, having a micro-electro-mechanical-system (MEMS).