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JP-2026075953-A - Measuring device and measuring system

JP2026075953AJP 2026075953 AJP2026075953 AJP 2026075953AJP-2026075953-A

Abstract

[Problem] To provide a measuring device that can detect the position and orientation of a writing instrument with a simple configuration. [Solution] The measuring device 6 includes an extraction unit 62 that extracts an identification portion from an image of the writing instrument 1. The measuring device 6 includes a first detection unit 63 that detects the position and orientation of the identification portion, and a second detection unit 64 that detects the position and orientation of the writing instrument 1 based on the position and orientation of the identification portion detected by the first detection unit 63. The identification portion is composed of a line 21a that extends circumferentially on the surface of the barrel 11 of the writing instrument 1. [Selection Diagram] Figure 4

Inventors

  • 塚田 海斗

Assignees

  • 三菱鉛筆株式会社

Dates

Publication Date
20260511
Application Date
20241023

Claims (6)

  1. A measuring device for measuring the state of a writing instrument having an identification portion for image processing, An extraction unit that extracts the identification portion from an image of a writing instrument, A first detection unit for detecting the position and orientation of the identified portion, The system includes a second detection unit that detects the position and orientation of a writing instrument based on the position and orientation of the identification portion detected by the first detection unit, The measuring device is characterized in that the identification portion includes a line extending circumferentially on the surface of the barrel of a writing instrument or a figure extending circumferentially on the surface of the barrel.
  2. The measuring device according to claim 1, wherein the identification portion is a line or figure depicted on an auxiliary member attached to the shaft cylinder.
  3. The aforementioned shaft cylinder has angles extending in the circumferential direction, The measuring device according to claim 1, wherein the line extending circumferentially on the surface of the shaft cylinder is formed at the corner.
  4. The measuring device according to claim 1 or 2, wherein the identification portion is formed such that the surface including the identification portion is perpendicular to the axis of the shaft cylinder.
  5. The measuring device according to claim 1 or 2, further comprising a tip calculation unit that calculates the position of the writing tip of a writing instrument based on the position and orientation of the writing instrument detected by the second detection unit.
  6. A measuring system for measuring the condition of a writing instrument, The measuring device according to claim 1, A writing instrument having an identification part, A measurement system characterized by comprising an imaging device for imaging a writing instrument.

Description

This invention relates to a measuring device and a measuring system. In the prior art, devices are known that measure the state of a writing instrument when a user is using it. For example, a device is known that measures information such as writing pressure and writing speed based on the output of multiple sensors arranged around the writing instrument (e.g., Japanese Patent Publication No. 2023-88242). Alternatively, a device is known that measures the amount of writing, etc., by placing a sensor or special mechanism inside the writing instrument (e.g., Japanese Patent Publication Nos. 2022-120519 and 2021-33563). Japanese Patent Publication No. 2023-88242Japanese Patent Publication No. 2022-120519Japanese Patent Publication No. 2021-33563 This is a perspective view of the measurement system in the embodiment.This is a perspective view of the first writing instrument in the embodiment.This is a perspective view of the auxiliary component of the first writing instrument.This is a block diagram of the measurement system in the embodiment.This is a flowchart of the control for measuring the operation of a writing instrument in the embodiment.This diagram illustrates the control process from acquiring the entire image to extracting the identified portion and fitting it with an ellipse.This is an explanatory diagram of the control system that detects the position and orientation of the circular identification part in the camera coordinate system and calculates the trajectory of the writing part.This is an explanatory diagram of the control system that fits an ellipse to lines extracted from an image.This diagram illustrates the imaging plane as seen from the perspective of an imaging device viewing a perfect circle.This is a diagram illustrating the ellipses contained in the image.This is the first explanatory diagram of a control system that calculates the center position and normal vector of a perfect circle in the camera coordinate system from an ellipse in an image.This is the second explanatory diagram for the control that calculates the center position and normal vector of a perfect circle in the camera coordinate system from an ellipse in an image.This is a perspective view of the second writing instrument in the embodiment.This is a perspective view of the third writing instrument in the embodiment. Referring to Figures 1 to 14, the measuring device and measuring system in this embodiment will be described. The measuring system in this embodiment comprises a measuring device for a writing instrument, a writing instrument, and an imaging device for imaging the writing instrument. The measuring device in this embodiment measures the state of the writing instrument, including its position and orientation. Figure 1 shows a perspective view of the measurement system in this embodiment. The measurement system 9 in this embodiment measures the position and orientation of the writing instrument 1 by processing a video of the user using the writing instrument 1. In this example, the user measures the state of the writing instrument 1 while holding it in their hand 47 and writing on paper 45. The paper 45 is placed on a workbench 42. The measurement system 9 includes an imaging device 5 that captures video footage of the user moving the writing instrument 1. In this embodiment, the imaging device 5 is a smartphone. However, the imaging device is not limited to this form; any device capable of capturing video footage of the writing instrument operated by the user can be used. For example, a video camera can be used as the imaging device. The measurement system 9 includes a measuring device 6 for measuring the state of the writing instrument 1. The measuring device 6 is connected to the imaging device 5 via a communication device 41. The video captured by the imaging device 5 is transmitted to the measuring device 6. The measuring device 6 extracts a two-dimensional image from the video and detects the position and orientation of the writing instrument 1 by analyzing the two-dimensional image. The measurement system 9 includes a communication device 41 for communication between the imaging device 5 and the measurement device 6. In this embodiment, the communication device 41 functions as a support member for supporting the imaging device 5. The position and orientation of the imaging device 5 in this embodiment are fixed. The communication device 41 has terminals for connecting the imaging device 5. The communication device 41 is configured to support the imaging device 5 by placing it on the communication device 41, and the terminals of the imaging device 5 are connected to the terminals of the communication device 41. Figure 2 shows a perspective view of the writing instrument in this embodiment. The writing instrument 1 in this embodiment is a ballpoint pen comprising a cylindrical barrel 11 and a refill 15 disposed inside the barrel 11. In this embodiment, the cross-sectional shape when the barrel 11 is cut by