| Abstract
ID |
|
1916 |
| Title |
|
Fabrication of a New Position Surveying System for the Underground Pipes Using Rotary Encoders |
| Category |
|
Equipment, Machines & Instruments: Mechatronics |
| Primary
author |
|
|
| Organization |
|
|
|
| Content |
|
Optical fiber cable for high-speed and large-capacity communication is usually covered by plastic pipe and buried under the ground. Then, we are required to grasp its real buried position before digging at the construction or the maintenance in order to prevent from the cutting of the optical fiber. However, once the optical fiber cable is buried under the ground, it is very difficult to confirm the buried position of the pipe, because the optical fiber cable and plastic cover pipe are not the metal.
A former way to confirm the buried position of the optical fiber cable is the ground penetrating radar method [1],[2]. The ground penetrating radar method is very useful for the metal. However, the optical fiber cable in plastic cover pipe is not metal. Another method is the elastic wave method [3]. In this method, a vibrator is put on the ground. The wave from the vibrator is detected by many in-lined receivers that are arrayed on the ground. However, the detection is only done at the place where the ground is covered by soil and the accuracy of the surveying is not good at the place where the position of the plastic cover pipe is so deep in the ground or in the different soils.
If we can detect directly the information of the buried position of the pipe by a new position surveying system that can move itself in the pipe, the problem of the former way to confirm the buried position of the optical fiber cable is solved.
This research aims to identify easily the buried position of the pipe, using the information of the buried position from the pipe. We use two rotary encoders that have pulleys contacting right and left walls of the buried pipe in order to detect directly the information of the buried position of the pipe. Output of the rotary encoder contacting the wall shows the length of the wall. Average of summation of the outputs of the right and the left rotary encoder shows moving distance of a surveying mechanism of the position surveying system. The curvature of the buried pipe is obtained by difference of the outputs of the right and the left rotary encoder. The position of buried pipe is identified by the moving distance and the curvature of the pipe. It is confirmed that the new position surveying system can identify the buried position of a pipe that is 20 m long and has loose curvature in the error of 5.6 mm. |
|
|
|
