Strobe-Light Landing Pad Navigation Using Passive Retroreflectors

Solution Overview

Problem

Urban air mobility vehicles require cost-effective, lightweight, and low-maintenance navigation systems for identifying and navigating to specific landing pads in vertiports, as traditional radar-based solutions are expensive, complex, and power-intensive.

Innovation Solution

A strobe-light-based navigation system using vehicle-mounted strobe lights and landing pads equipped with optical light passive retroreflectors, which utilize reflected strobe light pulses to identify specific landing pads and determine vehicle position, attitude, and velocity through pattern recognition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If radar-based navigation systems are used for UAM vehicles, then navigation precision and reliability are improved, but system cost, weight, complexity, and power consumption increase significantly

Engineering Contradiction:

Improvenavigation reliabilityVSAvoidsystem weight

Core Design Contradiction:

ReliabilityVSWeight of moving object

Solution Approach 1:

The patent replaces the radar-based electromagnetic navigation system with an optical navigation system using strobe lights and retroreflectors. This substitution transitions from a complex electronic radar system to a simpler optical system that uses standard aviation strobe lights and passive retroreflector arrays, significantly reducing weight and complexity while maintaining navigation functionality

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent creates an optical copy of the radar navigation concept by using reflected light pulses instead of radio waves. The retroreflector arrays create predictable light reflection patterns that replicate the navigation information function of radar, allowing the vehicle to determine position and orientation through image processing of reflected strobe light

Inventive Principle:

Principle #26Copying

2Reliability

If radar-based navigation systems are used for UAM vehicles, then navigation precision and reliability are improved, but system cost, weight, complexity, and power consumption increase significantly

Engineering Contradiction:

Improvenavigation reliabilityVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the radar-based electromagnetic navigation system with an optical navigation system using strobe lights and retroreflectors. This substitution transitions from a complex electronic radar system to a simpler optical system that uses standard aviation strobe lights and passive retroreflector arrays, significantly reducing weight and complexity while maintaining navigation functionality

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The retroreflector arrays passively return light to the source without requiring external power or active components. The system uses the vehicle's own strobe lights to illuminate the retroreflectors, which then reflect the light back for detection, creating a self-contained navigation system that eliminates the need for powered transponders or active beacons at the landing pads

Inventive Principle:

Principle #25Self-service

3Reliability

If radar-based navigation systems are used for UAM vehicles, then navigation precision and reliability are improved, but power consumption increases substantially

Engineering Contradiction:

Improvenavigation reliabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent uses periodic strobe light pulses instead of continuous radar transmission. The strobe lights flash at specific intervals, and the reflected light from retroreflectors is captured during these periodic pulses. This periodic operation dramatically reduces average power consumption compared to continuous radar operation while maintaining navigation accuracy through timing-based distance measurement

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The retroreflector arrays passively return light to the source without requiring external power or active components. The system uses the vehicle's own strobe lights to illuminate the retroreflectors, which then reflect the light back for detection, creating a self-contained navigation system that eliminates the need for powered transponders or active beacons at the landing pads

Inventive Principle:

Principle #25Self-service

4Reliability

If radar-based navigation systems are used for UAM vehicles, then navigation precision and reliability are improved, but maintenance requirements increase

Engineering Contradiction:

Improvenavigation reliabilityVSAvoidmaintenance requirements

Core Design Contradiction:

ReliabilityVSEase of repair

Solution Approach 1:

The retroreflector arrays passively return light to the source without requiring external power or active components. The system uses the vehicle's own strobe lights to illuminate the retroreflectors, which then reflect the light back for detection, creating a self-contained navigation system that eliminates the need for powered transponders or active beacons at the landing pads

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent uses standard aviation strobe lights that are already certified and widely available, replacing specialized radar equipment. These strobe lights are simpler, more reliable, and easier to replace if needed, while the passive retroreflectors require no maintenance beyond ensuring they remain clean and properly positioned

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Provides precise and efficient navigation with reduced costs, weight, and maintenance requirements, enabling safe and accurate landing of UAM vehicles.

Implementation Method 1

a reflected strobe image capturing system coupled to the reflection processing system, wherein the reflected strobe image capturing system is configured to capture images of reflected strobe light pulses received from a retro-reflector array

Methodology Applied

Scientific EffectRetro-reflection: Retroreflector

Data Source

PatentUS12379501B2Systems and methods for strobe-light-based navigation

Publication Date: 2025.08.05 HONEYWELL INTERNATIONAL INC

AI summary

Systems and methods for strobe-light-based navigation are provided. In one embodiment, a reflected strobe light navigation system for a vehicle comprises: a vehicle navigation system; a reflection processing system coupled to the vehicle navigation system, wherein the reflection processing system is configured to output a navigation solution to the vehicle navigation system; a strobe light generator system configured to transmit a light pulse from the vehicle; and a reflected strobe image capturing system coupled to the reflection processing system, wherein the reflected strobe image capturing system is configured to capture images of reflected strobe light pulses received from a retro-reflector array, wherein the reflected strobe light pulses comprise reflections of the light pulse reflected by the retro-reflector array; wherein the reflection processing system evaluates one or more image frames each comprising a pattern of reflected light pulse images produced from the reflected strobe light pulses to calculate the navigation solution.