Leak Detection System For City Water Distribution Systems

Today’s cities lose 20-30% of its drinking water due to pipe leaks.  Many of these leaks are too small to be noticed from the street level, and result in a large volume of water that is unaccounted for.  Other times, they fail catastrophically and result in flooding and large water losses. In the Mechatronics Research Lab, we have created a robot that is capable of scanning pipe walls autonomously, reporting back estimates for where leaks are located within the pipe.

In addition to building this robot, we research how the pipe interior can be cleaned, and how existing leaks can be repaired without cutting access to the water supply.  In addition, we will investigate ways to instrument pipes so that they are able to detect when they are about to fail.

On a larger scale, we are interested in pipe networks, developing algorithms to monitor and operate pipe networks in the most efficient manner.  We also want to develop a way to recharge robots within the pipe so they can sustain themselves for long-term missions.

Development of Micro AUVs for Pipe Inspection

Projects in the robotics category:

  • Biomimetics: Robotic Stingrays Biomimetics: Robotic Stingrays
  • Biomimetics: Robotic fish Biomimetics: Robotic fish
  • In-Pipe Leak Detection In-Pipe Leak Detection
  • Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks
  • Optical Assembly Station Optical Assembly Station
  • Palletizing Robots Palletizing Robots
  • High Speed Direct-Drive Robots High Speed Direct-Drive Robots

 

 

Robot Design

 Robot Prototype

 

A tetherless robot is developed for maneuvering inside 4-inch-diameter (10 cm) pipe networks. This ellipsoidal micro drone is capable of path following and making very tight turns. It will be used to carry leak sensors into water distribution networks and perform high speed, full coverage leak detection in every branch of the pipes.

Published in IROS 2015 paper

 

 

Swimming speed and turning radius are important measures of robot maneuverability. A test run in the open water shows that the robot is very good at maneuvering in water. It can swim easily at 1.3 ft/s (0.4m/s or about 5 body length/s) and turns at a 0.6 inch radius of curvature (1.5 cm or less than 0.2 body length).

 

RIM Propeller

 

 

The robot is actuated by a pair of RIM driven propellers. It is a brushless DC motor with its rotor replaced by a hubless propeller. Each motor-propeller assembly is measured to be 1.3 inch (33mm) in diameter and less than 0.5 inch (12mm) in thickness. This compact actuator is able to generate 0.4N of thrust given a 7.4V, 1A power supply.

Published in DSCC 2014 paper

 RIM propeller and a quarter

 

 

Biomimetic locomotion in liquid environments

Projects in the robotics category:

  • Biomimetics: Robotic Stingrays Biomimetics: Robotic Stingrays
  • Biomimetics: Robotic fish Biomimetics: Robotic fish
  • In-Pipe Leak Detection In-Pipe Leak Detection
  • Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks
  • Optical Assembly Station Optical Assembly Station
  • Palletizing Robots Palletizing Robots
  • High Speed Direct-Drive Robots High Speed Direct-Drive Robots

Biomimetic locomotion is of interest in applications where good cruising speeds, high maneuverability and stealth are needed. Current Biomimetic devices that use traditional discrete-stiff mechanisms have severe limitations because of their complexity. The proposed approach exploits the natural dynamics of a flexible structure in order to achieve the body motions needed to implement Biomimetic swimming performance.

 

 

Thermal Control of Robot in Cold and Hazardous Environment

Projects in the robotics category:

  • Biomimetics: Robotic Stingrays Biomimetics: Robotic Stingrays
  • Biomimetics: Robotic fish Biomimetics: Robotic fish
  • In-Pipe Leak Detection In-Pipe Leak Detection
  • Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks
  • Optical Assembly Station Optical Assembly Station
  • Palletizing Robots Palletizing Robots
  • High Speed Direct-Drive Robots High Speed Direct-Drive Robots

[slideshow_deploy id=’174’]

Liquid natural gas and liquid petroleum gas are stored in steel alloy tanks at approximately -160C and -45C, respectively. These tanks need to be periodically inspected for cracks, corrosion, and other defects. Currently the inspection process involves sending a human into the emptied tanks with inspection equipment. In order to make the tanks safe for human ingress they need to be warmed for 10-14 days. The cost of this shutdown is about 15 million dollars per day and is still hazardous for the human inspectors. This project is to develop an inspection robot that can enter the tanks at much lower temperatures thus reducing the maintenance costs and limit the risk to human inspectors. There are many robotic inspection systems out there, but these systems are not designed for cold and hazardous conditions, thus they would not be suitable for placement into the tanks in question. A new system needs to be designed which can work inside the tank under cryogenic temperatures and hazardous conditions to inspect the floor of the tank. Past work has been focused on the localization of the robot within the tank, and current work is investigating a thermal control system for the robot when operating inside the cold and hazardous environment.

 

 

High-Speed Large-Range Atomic Force Microscopy

Atomic force microscope(AFM) is a powerful and versatile instrument with a wide variety of applications ranging from imaging and nano-manipulation to characterizing mechanical properties of various types of samples. The speed limitations of this device however, have constrained its capabilities. In this research we develop controls, instrumentation and signal processing techniques to achieve ultra-high imaging speed for AFM and unlock its true ability. The new possibilities made available through the contributions of this research will be explored in areas such as materials, and biological sciences.

See our latest work on the design of a high-speed large-range atomic force microscope. This work is highlighted  in Boston Globe and MIT-news.

Optics

Multi_Act AFM

Left: A schematic view of the designed AFM and Right: the AFM setup with a close-up view of the multi-actuated scanner. Various components are labeled/numbered similarly in (a) and (b). The scanner is composed of a (from top to bottom) (1)fast/short-range out-of-plane actuator (Z2), (2) fast/short-range lateral positioner (X2) for raster
scan, (3) slow/large-range out-of-plane actuator (Z1), (4) slow/large-range lateral actuator (X1) for raster scan,and (5) slow/large-range lateral actuator for frameup/down motion (Y).

Click on each item to see the corresponding AFM videos of calcite etching captured with this AFM setup:  showing layer by layer removal of calcite terraces, deep pit formation and mono layer dissolution.

Multi-actuation can also be used to retroactively enhance existing AFM setups. See our paper on this approach here.

PI controlThe above figure shows an AS-130NM tube scanner with 130 µm lateral and 5 µm vertical range. This figure also shows an additional high-speed piezo flexure actuator mounted on top (left). On the right you can see the schematics of the experimental setup.

 

 

Soft Robot-Stingray

Other projects in the robotics category:

  • Biomimetics: Robotic Stingrays Biomimetics: Robotic Stingrays
  • Biomimetics: Robotic fish Biomimetics: Robotic fish
  • In-Pipe Leak Detection In-Pipe Leak Detection
  • Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks
  • Optical Assembly Station Optical Assembly Station
  • Palletizing Robots Palletizing Robots
  • High Speed Direct-Drive Robots High Speed Direct-Drive Robots

 

 

In Pipe Leak Detection

Projects in the robotics category:

  • Biomimetics: Robotic Stingrays Biomimetics: Robotic Stingrays
  • Biomimetics: Robotic fish Biomimetics: Robotic fish
  • In-Pipe Leak Detection In-Pipe Leak Detection
  • Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks Inspection Robots: Robots for Inspecting Liquefied Natural Gas Storage Tanks
  • Optical Assembly Station Optical Assembly Station
  • Palletizing Robots Palletizing Robots
  • High Speed Direct-Drive Robots High Speed Direct-Drive Robots


 

Project Overview

Leakage is the major factor for unaccounted losses in every pipe network around the world (oil, gas, or water). In most cases, the deleterious effects associated with the occurrence of leaks may present serious economical and health problems. Therefore, leaks must be quickly detected, located, and repaired. Unfortunately, most state-of-the-art leak detection systems have limited applicability, are neither reliable nor robust, while others depend on the user experience.

In this project we work towards a new in-pipe leak detection system. Our proposed robotic system is able to detect leaks in pipes in a reliable and autonomous fashion. The idea is that the robot is inserted into the network via special insertion points. The robotic system inspects the network and sends signals wirelessly via relay stations to a computer/base station. Leak signals stand out clearly on the occurrence of leaks, eliminating the need for the user experience.

The latter is achieved via a detector that is based on identifying a clear pressure gradient in the vicinity of leaks. Detection is based on identifying the existence of a localized pressure gradient (∂p/∂r , where r stands for the radial coordinate of the pipe). This pressure gradient appears always in pressurized pipes in the vicinity of leaks and is independent of the pipe size and/or pipe material. Moreover, the pressure gradient exists in different media inside pipes, which makes the detection method widely applicable (gas, oil, water pipes, etc.). Moreover, the proposed detector can sense leaks at any angle around the circumference of the pipe with only two sensors.

Reliable Power Grid Operation & Control

Unlike conventional power generation, renewable energy and energy management technologies may be classified as “Variable Energy Resources” because of their intermittency. Recently, regulators and electric utilities recognize that this variable nature puts a stress on many aspects of the electrical power grid. In such a scenario, conservative central planners would typically invest in additional generation, transmission, and distribution capacity – thereby adding to the “real cost” of renewable energy and energy management technologies. Instead, the true success of renewable energy and energy management technologies depends on the robust dynamic control and operation of the electrical power grid at all of its respective layers.

This research project seeks to simulate the operation and control of the electrical power grid so as to understand its reliability at increasing levels of penetration of variable energy resources. In order to do so, a multi-level simulation platform is being developed.