Surface Shape Measurement Probe with Dynamic Reference Selection

Solution Overview

Problem

Existing measurement apparatuses face challenges in accurately measuring the shape of large object surfaces due to discontinuities between multiple reference members, leading to inaccurate scanning results as the probe moves across the surface.

Innovation Solution

A measurement apparatus with a probe, multiple reference members, and detection units that adjust the detection results based on scanning ranges, allowing the processing unit to select and combine reference members differently for each range to minimize discontinuities and improve accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If a plurality of reference members are arranged in the scanning direction to enlarge the scanning range, then the scanning range is increased, but the measurement continuity deteriorates due to discontinuities between reference members

Engineering Contradiction:

Improvescanning rangeVSAvoidmeasurement continuity

Core Design Contradiction:

Area of stationary objectVSReliability

Solution Approach 1:

The patent applies dynamics by making the selection of reference members and detection units dynamic rather than fixed. The processing unit dynamically selects which reference member and detection unit combination to use based on the probe's current position in the scanning direction. This dynamic adaptation allows the system to maintain measurement continuity across the entire scanning range by seamlessly transitioning between different reference member combinations as the probe moves from one range to another, thereby resolving the contradiction between enlarged scanning range and measurement continuity.

Inventive Principle:

Principle #15Dynamics

2Device complexity

If the same reference member is used for all detection units, then the system structure is simplified, but the measurement precision deteriorates when the probe moves across different scanning ranges

Engineering Contradiction:

Improvesystem structureVSAvoidshape measurement accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent applies local quality by assigning different reference members to different detection units based on their local scanning ranges. Instead of using a uniform reference member configuration throughout the entire scanning range, the system configures each detection unit with reference members optimized for its specific local range. The processing unit then selects the appropriate detection unit and reference member combination based on the probe's position, ensuring high measurement precision for each local region while maintaining overall system functionality.

Inventive Principle:

Principle #3Local quality

3Area of stationary object

If multiple reference members are used to cover a large scanning area, then the scanning range is enlarged, but the measurement precision deteriorates due to discontinuities between reference members

Engineering Contradiction:

Improvescanning rangeVSAvoidshape measurement accuracy

Core Design Contradiction:

Area of stationary objectVSMeasurement precision

Solution Approach 1:

The patent applies dynamics by making the selection of reference members and detection units dynamic rather than fixed. The processing unit dynamically selects which reference member and detection unit combination to use based on the probe's current position in the scanning direction. This dynamic adaptation allows the system to maintain measurement continuity across the entire scanning range by seamlessly transitioning between different reference member combinations as the probe moves from one range to another, thereby resolving the contradiction between enlarged scanning range and measurement continuity.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies feedback by using the probe's position information as feedback to control the selection of reference members and detection units. The processing unit continuously monitors the probe's position in the scanning direction and uses this information to determine which combination of reference members and detection units should be active. This feedback mechanism ensures that the system always uses the most appropriate reference members for the current scanning position, maintaining high measurement precision across the entire enlarged scanning range.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS9982993B2Measurement apparatus and measurement method

Publication Date: 2018.05.29 CANON KK

AI summary

The present invention provides a measurement apparatus for measuring a shape of a surface of an object, including a probe configured to be scanned on the surface of the object, a plurality of reference members configured to be arranged in a scanning direction of the probe, a plurality of detection units configured to be provided at different positions of the probe in the scanning direction and each configured to detect a distance from a reference member which has been selected from the plurality of reference members in accordance with a position of the probe in the scanning direction, and a processing unit configured to obtain shape information of the surface of the object by obtaining position information of the probe based on at least one of detection results of the plurality of detection units while scanning the probe.