Optical Sensor Speed Estimation for Indoor Navigation

Solution Overview

Problem

Existing navigation techniques in portable devices face limitations, including reliance on clear line of sight for satellite navigation, precision issues with wireless signal trilateration, and degradation of inertial navigation due to errors in MEMS-based sensors, especially in varying orientations and indoor environments.

Innovation Solution

The use of an optical sensor, such as a CMOS camera, to process sequences of samples and determine navigational constraints, including speed and velocity, to provide an independent or supplementary navigation solution, leveraging optical flow analysis and context determination to enhance navigation accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If satellite-based navigation is used, then navigation accuracy is improved, but the system becomes dependent on clear line of sight which is not always available

Engineering Contradiction:

Improvenavigation accuracyVSAvoidavailability in various environments

Core Design Contradiction:

Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent introduces optical sensors (cameras) as an intermediary measurement system that captures visual data from the environment. This intermediary allows the device to determine motion and position through image processing and optical flow analysis, providing navigation capability without requiring direct satellite signal access. The optical sensor system acts as a mediator between the device and the environment, enabling navigation in environments where satellite signals are unavailable.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the traditional mechanical/optical inertial measurement system (accelerometers and gyroscopes) with an optical sensor-based system. Instead of relying on mechanical sensors that suffer from drift and calibration issues, the system uses optical flow analysis and image processing to determine motion parameters. This substitution eliminates the fundamental limitations of MEMS-based inertial sensors while providing a new approach to motion detection.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Adaptability or versatility

If inertial navigation is used, then self-contained navigation is achieved, but measurement precision degrades rapidly due to errors in MEMS sensors

Engineering Contradiction:

Improveself-contained navigation capabilityVSAvoidnavigation accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent replaces the traditional mechanical/optical inertial measurement system (accelerometers and gyroscopes) with an optical sensor-based system. Instead of relying on mechanical sensors that suffer from drift and calibration issues, the system uses optical flow analysis and image processing to determine motion parameters. This substitution eliminates the fundamental limitations of MEMS-based inertial sensors while providing a new approach to motion detection.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces optical sensors (cameras) as an intermediary measurement system that captures visual data from the environment. This intermediary allows the device to determine motion and position through image processing and optical flow analysis, providing navigation capability without requiring direct satellite signal access. The optical sensor system acts as a mediator between the device and the environment, enabling navigation in environments where satellite signals are unavailable.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If optical sensor-based navigation is used, then independence from satellite and inertial systems is achieved, but device complexity increases

Engineering Contradiction:

Improveindependence from other navigation techniquesVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent leverages the optical sensor (camera) that is already present in portable devices for multiple functions: it serves both as a communication/capture device and as a navigation sensor. By making the camera multi-functional, the system avoids adding dedicated hardware components, thereby reducing the increase in device complexity while achieving independence from satellite and inertial navigation systems.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system uses the optical sensor to capture environmental data that is then processed to determine motion and position. The same optical sensor that is already part of the device's standard configuration is repurposed for navigation, making the system self-sufficient without requiring external infrastructure or additional specialized hardware. The device serves its own navigation needs using existing components.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS10302669B2Method and apparatus for speed or velocity estimation using optical sensor

Publication Date: 2019.05.28 INVENSENSE INC

AI summary

Systems and methods are disclosed for estimating speed and/or velocity for a portable device using an optical sensor. The optical sensor may capture a plurality of samples to be processed to estimate speed. The speed or velocity may be estimated based on a determined context and/or usage of the portable device. The estimated speed or velocity may be used to supplement other navigational solutions or may be used independently.