Sensor Cleaning Flow Body Using Coanda Effect
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cleaning systems for sensor apparatuses, such as camera lenses and lidar, face issues with uncontrolled water runoff, incomplete cleaning due to wind sensitivity, and obstructed fields of view, leading to aesthetic and functional impairments, while requiring excessive cleaning agent supply and complex, expensive designs.
Innovation Solution
A stationary flow body that guides the cleaning fluid tangentially along the surface, utilizing the Coandă and Bernoulli effects to ensure reliable cleaning at high speeds with reduced fluid pressure and quantity, and a recessed nozzle installation that avoids obstructing the sensor's field of view, combined with a collecting chamber and blowing nozzles for efficient fluid recovery and surface drying.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a spray nozzle is positioned laterally and protruding to clean the sensor surface, then cleaning effectiveness is improved, but the field of view is obstructed and aerodynamics are adversely affected
Solution Approach 1:
The spray nozzle is designed as a lifting nozzle that can move between a retracted parking position and an extended operating position. During normal operation, the nozzle remains retracted to avoid obstructing the field of view. When cleaning is required, the nozzle extends to deliver the cleaning jet at the optimal position for effective cleaning of the sensor surface.
Solution Approach 2:
The cleaning system transitions from a lateral spray approach to an axial spray approach, where the cleaning jet is directed along the sensor axis from the rear side of the sensor apparatus. This dimensional change allows the nozzle to be positioned without obstructing the lateral field of view while maintaining cleaning effectiveness on the sensor surface.
2Reliability
If cleaning agent supply is increased to ensure complete wetting against wind effects, then cleaning reliability is improved, but the required supply volume increases and system complexity increases
Solution Approach 1:
The system utilizes a high-pressure pump to generate a concentrated cleaning jet with sufficient pressure to overcome wind effects and maintain complete wetting of the sensor surface. The high-pressure hydraulic approach allows using less cleaning agent volume while achieving the same cleaning reliability compared to low-pressure systems that would require larger volumes.
Solution Approach 2:
The spray nozzle is positioned eccentrically with respect to the sensor axis and protrudes laterally to create an asymmetric spray pattern that optimizes the cleaning jet trajectory. This asymmetric positioning, combined with the axial spray direction, ensures the cleaning fluid effectively reaches the sensor surface even under wind influence, reducing the need for excessive cleaning agent supply.
3Object-affected harmful factors
If lifting nozzles are made movable between retracted and extended positions, then field of view obstruction is reduced, but device complexity and susceptibility to wear increase
Solution Approach 1:
The lifting nozzle incorporates a movable mechanism that allows transition between retracted and extended positions. This dynamic positioning reduces field of view obstruction during normal operation while enabling effective cleaning when activated. The mechanism is designed to minimize wear through appropriate material selection and lubrication, balancing mobility benefits with durability requirements.
4Reliability
If the cleaning jet pressure is increased to overcome wind diversion, then cleaning completeness is improved, but the required supply pressure and quantity increase
Solution Approach 1:
The system employs a high-pressure pump capable of generating elevated cleaning jet pressure to counteract wind diversion effects. The increased supply pressure ensures the cleaning jet maintains its trajectory and complete wetting capability under windy conditions, achieving cleaning completeness without requiring proportionally larger cleaning agent volumes.
Solution Approach 2:
The eccentric and protruding nozzle positioning creates an asymmetric spray configuration that optimizes jet direction and pressure distribution. This asymmetric arrangement, combined with axial spraying, ensures efficient use of the supplied pressure by directing the cleaning force precisely where needed, reducing overall pressure requirements compared to symmetric lateral spraying configurations.
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 solution provides a reliable, wind-insensitive cleaning process with reduced agent supply, prevents unappealing runoff, maintains the sensor's field of view, and optimizes aerodynamics and aesthetics, allowing for efficient and effective cleaning and fluid recovery.
Implementation Method 1
the outer surface of the flow body is oriented so as to be substantially tangential to the adjoining surface to be cleaned... the flow body simultaneously serves for guiding a fluid stream flowing from the spray nozzle to the surface
Implementation Method 2
utilizing the Coandă and Bernoulli effects to ensure reliable cleaning at high speeds with reduced fluid pressure and quantity
Data Source
AI summary
An optically, aerodynamically and economically optimized and particularly wind-insensitive cleaning apparatus for cleaning a surface of a sensor apparatus of a vehicle with a fluid cleaning agent. The surface is delimited by an encircling outer edge which is arranged so as to be substantially flush with a surrounding outer surface region, and the cleaning apparatus includes a flow body for guiding a fluid stream flowing from the spray nozzle to the surface and flowing away from the surface, wherein the flow body at least sectionally adjoins the outer edge of the surface, in particular completely surrounds the outer edge, and, at the outer edge, an outer surface of the flow body is oriented so as to be substantially tangential to the adjoining surface.