Bridge inspection robot capable of climbing obstacle

• US 8,924,018 B2
• Filed: 04/20/2009
• Issued: 12/30/2014
• Est. Priority Date: 04/23/2008
• Status: Expired due to Fees

• Current Assignee: Expressway & Transportation Research Institute
• Original Assignee: Expressway & Transportation Research Institute
• Inventors: Lee, Byeong-Ju, Shin, Jae-In, Park, Chang-Ho, Park, Young-Ho, Nam, Moon-Seok
• Primary Examiner(s): Edwards, Jerrah
• Application Number:
  US12/989,605
• Publication Number:
  US 20110106313A1
• Time in Patent Office: 2,080 Days
• Field of Search: 700/259, 180/8.2
• US Class Current: 700/259
• CPC Class Codes: B25J 19/021 Optical sensing devices
• CPC Class Codes: B25J 5/007 mounted on wheels
• CPC Class Codes: E01D 19/106 Movable inspection or maintenance platforms, e.g. travelling scaffolding or vehicles specially designed to provide access to the undersides of bridges lifting devices for movable platforms on vehicles in general B66F11/04
• CPC Class Codes: E01D 19/16 Suspension cables; Cable clamps for suspension cables ; Pre- or post-stressed cables
• CPC Class Codes: G02B 27/648 for automatically maintaining a reference alignment, e.g. in self-levelling surveying instruments surveying instruments per se G01C
• CPC Class Codes: G03B 2205/00 Adjustment of optical system relative to image or object surface other than for focusing
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur

Abstract

Provided is a bridge inspection robot that avoids obstacles is provided. An ascending/descending portion corresponds to a gap distance between a first and second girder flange provided at the upper side of a bridge pier. An obstacle detection portion detects the obstacle and a photographing altitude control portion detects an altitude change of an image photographing portion according to obstacle height when the robot main body climbs up/down or avoids the obstacle, and adjusts a photographing height to correspond to the altitude change. A position calculation portion measures a mobile position of the robot main body corresponding to a consecutively photographed image, to calculate axis coordinates. An image processing portion receives the consecutively photographed images and coordinates, to confirm the crack elements corresponding to images and produce an image of an actual position coordinate of the corresponding image.

Claims

1. A bridge inspection robot which is capable of avoiding an obstacle, the bridge inspection robot comprising:

an ascending/descending portion which is extended to correspond to a gap distance between a flange of a first girder and a flange of a second girder which are provided at the upper side of a pier (L) of a bridge in which a robot main body (101) climbs up/down or avoids an obstacle, when the robot main body moves on the flanges, for example, along a bridge inspection path;

an obstacle detection portion which detects the obstacle which exists on the flanges;

a photographing altitude control portion which detects an altitude change of an image photographing portion according to height of the obstacle when the robot main body climbs up/down or avoids the obstacle, and adjusts a photographing height of the image photographing portion so as to correspond to the altitude change, to thus make the image photographing portion have a z-axis coordinate of an identical height all the time;

a position calculation portion which measures mobile positions of the robot main body which corresponds to consecutive images photographed by the image photographing portion, to thus calculate x/y-axis coordinates of the image photographing portion;

an image processing portion which receives the consecutively photographed images and x/y/z-axis coordinates corresponding to the consecutively photographed images, to thus continuously confirm actual crack elements corresponding to the consecutively photographed images and to thus produce recognizable consecutively photographed images of actual position coordinates of the corresponding consecutively photographed images; and

a slope adjustment portion which detects a slope of the robot main body when the robot main body climbs up/down an obstacle, and adjusts the slope of the image photographing portion to correspond to the detected slope.

2. The bridge inspection robot according to claim 1, wherein the slope adjustment portion comprises:

a slope detection sensor which detects a slope of the robot main body when the ascending/descending portion climbs up/down an obstacle; and

a camera angle adjustment portion which adjusts a photographing angle of a couple charged device (CCD) camera of the image photographing portion to correspond to the slope detected by the slope detection sensor and which makes the CCD camera photograph while maintaining the state where the bridge lower surface is perpendicular with the CCD camera.

3. The bridge inspection robot according to claim 2, wherein the slope detection sensor is provided in the inside of the robot main body and comprises:

a plurality of electrode rods covered with a glass tube which is filled with an electrolyte therein, in which the electrolyte in the inside of the glass tube is slanted and the slope is measured through a changed resistance value of the electrode rods according to a change rate of the electrolyte which is filled between the electrode rods, when the slope detection sensor is slanted.

4. The bridge inspection robot according to claim 2, wherein the camera angle adjustment portion comprises:

a rotational frame which supports the CCD camera, a base plate which enables the rotational frame to be rotatably combined through a hinge portion; and

a biometal wire which is guided by a guide portion and contracted and extended by an electric signal to thus make the rotational frame rotate.

5. The bridge inspection robot according to claim 1, wherein the photographing altitude control portion comprises:

an altitude detection sensor which detects whether a photographing height of the image photographing portion is changed when the ascending/descending portion climbs up/down an obstacle which exists on the bridge inspection path and calculates a z-axis position coordinate of the image photographing portion; and

a camera height adjustment portion which adjusts the photographing height of the CCD camera so as to correspond to the z-axis position coordinate of the image photographing portion detected by the altitude detection sensor, and makes the CCD camera photograph while having a z-axis position coordinate of a constant height with respect to the bridge lower surface on the bridge inspection path.