TOF Distance Measuring Device Multipath Error Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Distance measuring devices using time of flight (TOF) technology face measurement errors due to the multipath phenomenon in environments with highly reflective materials, requiring significant operator effort to create correction formulas by attaching reflective tape at multiple positions and measuring distances before and after its removal.
Innovation Solution
A method and device that automate the creation of correction formulas by measuring distances to reflective tape both with and without multipath interference, allowing for automatic conversion of affected distances to accurate distances, reducing operator workload by pasting reflective tape only once and using the device to scan and calculate correction values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If reflective tape is attached to target object at multiple predetermined positions for correction formula creation, then measurement precision is improved, but loss of time increases due to huge work amount and working time
Solution Approach 1:
The distance measuring device automatically performs the correction formula creation process by itself. The device attaches the reflective tape to the target object, measures distances at multiple predetermined positions, and generates the correction formula without operator intervention. This self-service approach eliminates the huge work amount and working time required for manual correction formula creation while maintaining measurement precision.
Solution Approach 2:
The device performs preliminary attachment of the reflective tape to the target object at multiple predetermined positions before actual distance measurements are taken. This preliminary action enables the automatic creation of the correction formula, which is then stored and applied during subsequent measurements, significantly reducing the time required for each measurement operation.
2Measurement precision
If manual measurement and correction formula creation is performed at multiple positions, then measurement precision is improved, but ease of operation deteriorates due to huge work amount
Solution Approach 1:
The distance measuring device performs the entire correction formula creation process automatically without operator intervention. The device itself attaches the reflective tape, measures distances at multiple predetermined positions, calculates the correction formula, and stores it. This eliminates the huge work amount and complexity of manual operations while maintaining high measurement precision.
Solution Approach 2:
The device merges multiple separate operations (reflective tape attachment, distance measurement at multiple positions, correction formula calculation, and storage) into a single automated process. This integration eliminates the need for operators to perform each step manually, significantly improving ease of operation while maintaining measurement precision.
3Measurement precision
If reflective tape is attached at multiple predetermined positions for correction, then measurement precision is improved, but device complexity increases due to multiple measurement steps
Solution Approach 1:
The distance measuring device automatically manages the entire correction formula creation process, including attaching the reflective tape at multiple predetermined positions, measuring distances, calculating the correction formula, and storing it. This self-service capability simplifies the operation for users while the device internally handles the complexity of multiple measurement steps and calculations.
Solution Approach 2:
The device performs preliminary attachment of the reflective tape and preliminary measurements at multiple positions to create the correction formula before actual distance measurements are taken. This preliminary action consolidates the complex multi-step process into a one-time setup, reducing the perceived complexity during normal operation while maintaining high measurement precision.
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
Significantly reduces operator workload and time by automating the creation of correction formulas, enabling precise distance measurements even in multipath environments with minimal operator intervention.
Implementation Method 1
a light emitting section that emits irradiation light toward the target object; a light receiving section that detects reflected light from the target object
Implementation Method 2
a distance computing section that calculates the distance to the target object on a basis of time of flight of the reflected light detected at the light receiving section
Implementation Method 3
a material (so-called retroreflective material) having characteristics of reflecting light having been incident on the target object in the direction of incidence
Data Source
AI summary
At a preparatory step for correction, in a state that a reflective tape made with a retroreflective material is pasted in advance onto a floor surface of a measurement space in a direction away from the distance-measuring device, a distance La to an inside area of the reflective tape, and a distance Lb to an outside area of the reflective tape adjacent to the inside area are measured by the distance-measuring device, while measurement positions Y are being scanned along the reflective tape. A correction formula for converting the distance Lb to the distance La is created from a relationship between the distance La and the distance Lb obtained at each measurement position Y. At an actual measurement step, a distance (actual measurement value x) to the target object measured by the distance-measuring device is corrected in accordance with the correction formula, and a measurement-distance corrected value y is calculated.