Intelligent Actuators Realizing Snake-like Small Robot for Pipe Inspection

2006 ◽  
Author(s):  
Akina Kuwada ◽  
Kodai Tsujino ◽  
Koichi Suzumori ◽  
Takefumi Kanda
Keyword(s):  
Pipe Inspection ◽  
Small Robot ◽  
Intelligent Actuators

Guided Wave Focusing Mechanics in Pipe

2003 ◽  
Author(s):  
Takahiro Hayashi ◽  
Koichiro Kawashima ◽  
Zongqi Sun ◽  
Joseph L. Rose
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Guided Waves ◽  
Wave Structure ◽  
Guided Wave ◽  
Pipe Inspection ◽  
Specific Point ◽  
Wave Focusing ◽  
Beam Focusing ◽  
Subsequent Time

Guided waves can be used in pipe inspection over long distances. Presented in this paper is a beam focusing technique to improve the S/N ratio of the reflection from a tiny defect. Focusing is accomplished by using non-axisymmetric waveforms and subsequent time delayed superposition at a specific point in a pipe. A semi-analytical finite element method is used to present wave structure in the pipe. Focusing potential is also studied with various modes and frequencies.

Active Damping of a Large Flexible Manipulator With a Short-Reach Robot

1996 ◽  
Vol 118 (4) ◽  
pp. 704-713 ◽  
Author(s):  
I. Sharf
Keyword(s):  
Vibration Suppression ◽  
Controller Design ◽  
Reaction Force ◽  
Control Variable ◽  
Active Damping ◽  
Flexible Manipulator ◽  
Design Problems ◽  
Flexible Arm ◽  
Six Degree Of Freedom ◽  
Small Robot

This paper deals with manipulator systems comprising a long-reach manipulator (LRM) with a short-reach dextrous manipulator (SRM) attached to its end. The former, due to its size, is assumed to have significant structural flexibility, while the latter is modeled as a rigid robot. The particular problem addressed is that of active damping, or vibration suppression, of the LRM by using SRM specifically for that purpose Such a scenario is envisioned for operations where the large manipulator is used to deploy the small robot and it is necessary to damp out vibrations in LRM prior to operating SRM. The proposed solution to the problem uses the reaction force from SRM to LRM as a control variable which allows to effectively decouple the controller design problems for the two manipulators. A two-stage controller is presented that involves first, determining the trajectory of the short manipulator required to achieve a desired damping wrench to the supporting flexible arm and subsequently, brings the small manipulator to rest. Performance of the active damping algorithm developed is illustrated with a six-degree-of-freedom rigid manipulator on a flexible mast. Comparison to an independent derivative joint controller is included. The paper also discusses how the proposed methodology can be extended to address other issues related to operation of long-reach manipulator systems.

scholarly journals Ultrasonic multi-skip tomography for pipe inspection

2014 ◽  
Author(s):  
Arno Volker ◽  
Tim van Zon
Keyword(s):  
Pipe Inspection
Sign in / Sign up

Export Citation Format

Share Document