Waveguide Sensor Cover Fouling Detection for Autonomous Vehicles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Self-driving vehicles face operational limitations due to signal degradation from water, ice, dirt, or debris on sensor lenses, which can impede object detection and autonomous driving capabilities.
Innovation Solution
A sensor assembly with a waveguide layer on the sensor surface, utilizing a laser to emit light that is affected by precipitation or fouling, allowing for direct detection and determination of their presence, enabling activation of a cleaning system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If additional sensors are added to detect fouling on the sensor surface, then detection capability is improved, but device complexity and space requirements increase
Solution Approach 1:
The waveguide layer is integrated into the existing sensor assembly structure, allowing the same optical path to serve both the primary sensing function and the fouling detection function. The waveguide layer guides light from the emitter device through the sensor aperture window, and variations in the guided light signal indicate fouling conditions, thus achieving multiple functions with a single integrated structure
Solution Approach 2:
The waveguide layer acts as an intermediary element between the emitter device and the detector device. It transfers optical signals through the sensor assembly while being sensitive to fouling on the sensor aperture window, enabling indirect detection of fouling conditions without requiring direct contact with the contaminated surface
2Reliability
If the sensor assembly structure is modified to include waveguide layer, then fouling detection is enabled, but manufacturing complexity increases
Solution Approach 1:
The waveguide layer is configured with specific optical parameters (refractive index, thickness, geometry) that enable it to guide light effectively while remaining sensitive to fouling conditions. By optimizing these parameters, the layer achieves the desired detection sensitivity without requiring complex manufacturing processes
Solution Approach 2:
The sensor assembly integrates multiple materials with different properties: the waveguide layer (with high refractive index for effective light guiding), the base layer (transparent substrate), and the sensor aperture window. This composite structure combines the advantages of each material to achieve both fouling detection capability and manufacturability
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
This approach provides efficient and effective detection of water or fouling on sensor surfaces without occupying window space or requiring additional sensors, ensuring reliable operation in adverse conditions and maintaining autonomous driving capabilities.
Implementation Method 1
The waveguide layer has a waveguide pattern extending between a first side and a second side of the waveguide layer. The emitter device is operatively coupled to the first side of the waveguide layer. The emitter device is configured to emit a signal of a selected wavelength having a first waveform for propagation along the waveguide pattern.
Implementation Method 2
The emitter device may be a laser. The emitter device is configured to emit a signal of a selected wavelength having a first waveform for propagation along the waveguide pattern.
Implementation Method 3
The base layer is configured to pass signals of one or more wavelengths therethrough. The signal of the selected wavelength may be an optical or infrared signal.
Data Source
AI summary
The technology relates to detecting water or fouling on the exterior surface of a sensor cover, for instance due to precipitation or debris (fouling). Such objects on the sensor cover surface may degrade operation of the sensor, which can be problematic for vehicles operating in an autonomous driving mode. According to an aspect of the technology, a waveguide layer is provided on the sensor cover. A laser emits light at a selected wavelength along one side of the waveguide layer. The light waveform propagating along the waveguide layer is affected (distorted) by precipitation and/or fouling on the surface of this layer. A detector receives the distorted waveform. The system determines whether water and/or fouling is present based on the received waveform. This allows the system to determine whether to activate a cleaning module or to factor in the information when processing received sensor data.