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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Development of Robotic Crawlers for Inspection of Radioactive Waste Tanks and Transfer Lines - 19573

The leaks in the primary liner of Double Shell Tank (DST) 241-AY-102 have motivated a number of research efforts to develop inspection tools that can obtain information regarding the integrity of the Hanford DSTs. Recently, there have been additional concerns regarding the DST secondary liners as well various pipelines within the waste transfer system. Over the past few years, Florida International University (FIU) has developed a pneumatic pipe crawler that can navigate through 3- and 4-inch diameter pipes and provide visual feedback while traveling through pipelines in excess of 100 feet and multiple 90 degree elbows. Recent updates to the crawler include a new sensor module that can provide information regarding environmental conditions within the pipeline and a mapping of the interior surface of the line. The sensor module is a carousel type device that can rotate 360 degrees and is placed near the front of the 3- and 4- inch crawler. The module can house a number of sensors including temperature, pressure, radiation, Lidar, optical camera and an inertial measurement unit (IMU). The intent of the module is to improve the functionality of the crawler by providing environmental conditions within the pipe and internal surface topography maps that can assist in understanding potential wear, pitting or thinning of the pipe. In addition to the 3- and 4-inch crawler, FIU is developing a 6-inch crawler that utilizes the same principles as the smaller unit. The objective of this tool is to navigate through the 6-inch drain lines leading to the drain channels within the foundation underneath the secondary liner of the DSTs. This crawler will house a miniature rover that will be deployed at the end of the drain pipe, where it connects to the foundation. The miniature rover will operate upside down, via magnets, underneath the secondary liner within the drain slots and provide visual information regarding the condition of the secondary liner. Thinning of the secondary liner has been noted from the annulus of the some of the DSTs, but it is unclear if the thinning is isolated to locations near the annulus. (authors)

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DOE OSTI2022

Project Title: Development of a Pipe Crawler Inspection Tool for Fossil Energy Power Plants (Final Report)

This research effort focuses on the development of a pipe crawler inspection tool for fossil energy power plants. The pipe crawler is tethered and can navigate through 2 inch pipes that are often found in various systems within a power plant. The crawler can navigate through straight pipes and 180 degree elbows and includes instrumentation that can assess the integrity of the pipes. The sensors include a UT sensor for measuring the thickness of the pipe, a range finder and a camera. An additional module is used to prep the surface of the pipe prior to taking thickness measurements. Both bench scale and engineering scale testing was conducted to demonstrate the concept. Multiple crawlers were created and tethered together to distribute the load of the tether so that the crawler can navigate longer pipe distances.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2013

Improved third generation peristaltic crawler for removal of high-level waste plugs in United States department of energy Hanford site pipelines

There are approximately 56 million gallons (212 km{sup 3}) of high level waste (HLW) at the U.S. Department of Energy (DOE) Hanford Site. It is scheduled that by the year 2040, the HLW is to be completely transferred to secure double-shell tanks (DST) from the leaking single-tanks (SST) via transfer pipeline system. Blockages have formed inside the pipes during transport because of the variety in composition and characteristics of the waste. These full and partial plugs delay waste transfers and require manual intervention to repair, therefore are extremely expensive, consuming millions of dollars and further threatening the environment. To successfully continue the transfer of waste through the pipelines, DOE site engineers are in need of a technology that can accurately locate the blockages and unplug the pipelines. In this study, the proposed solution to remediate blockages formed in pipelines is the use of a peristaltic crawler: a pneumatically/hydraulically operated device that propels itself in a worm-like motion through sequential fluctuations of pressure in its air cavities. The crawler is also equipped with a high-pressure water nozzle used to clear blockages inside the pipelines. The crawler is now in its third generation. Previous generations showed limitations in its durability, speed, and maneuverability. Latest improvements include an automation of sequence that prevents kickback, a front-mounted inspection camera for visual feedback, and a thinner wall outer bellow for improved maneuverability. Different experimental tests were conducted to evaluate the improvements of crawler relative to its predecessors using a pipeline test-bed assembly. Anchor force tests, unplugging tests, and fatigue testing for both the bellow and rubber rims have yet to be conducted and thus results are not presented in this research. Experiments tested bellow force and response, cornering maneuverability, and straight line navigational speed. The design concept and experimental test results are reported. (authors)

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DOE OSTI2021

IN-SERVICE INSPECTION OF EXTENDED DRY STORAGE OF SPENT NUCLEAR FUEL, PART I: CRAWLER TECHNOLOGY DEVELOPMENT

This paper describes development and demonstration of remote crawling systems to support periodic examinations of interim dry storage system (DSS) canisters for spent nuclear fuel in the USA. Specifically, this work relates to robotic crawler developments for “canister” based DSS systems which form the majority population of DSSs, in the USA, for interim storage of spent nuclear fuel. Consideration of potential degradation of the welded stainless-steel canister in these systems is required for continued usage in the period of extended operation (PEO) beyond their initial licensed or certified terms. Challenges associated with performing the periodic examinations are associated with physical access to the canister surface which is constrained due to narrow annulus spaces between the canister and the overpack, tortuous entry pathways, and high temperatures and radiation doses that can be damaging to materials and electronics. Motivations for performing periodic examinations and developing robotic crawlers for performing those examinations remotely will be presented and several activities to demonstrate robotic crawlers for different DSS systems are summarized.

nondestructive examination (NDE), Dry Cask Storage↗
DOE OSTI2022

Development of a Pipe Crawler Inspection Tool for Fossil Energy Power Plants

This document presents the final report of the research activity completed during the four years of the project and includes the major challenges and accomplishments. The report presents specific details of the engineering processes and methodologies used to develop the robotic crawler and complete the project milestones. In particular, the report includes sections that address the problem statement, background, development of crawler modules, bench scale testing, simulation development and full scale testing. The report concludes with a discussion on potential paths forward and concluding remarks.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2020

Savannah River Site H-Canyon Process Exhaust Tunnel Inspection Crawler Development - 20036

This paper covers development of a remote crawler used to inspect a subterranean radiochemical process ventilation tunnel located at the Savannah River Site near Aiken, SC. The purpose of the inspection was to ascertain the apparent structural condition of the tunnel with video footage. Manned entry is prohibited due to the hazardous environment requiring a fully-remote approach. The inspection system used high-definition cameras to archive over 1000 linear feet in the tunnel. While previous inspections had been undertaken, this crawler was developed to overcome obstacles that had put tunnel regions out of reach of prior inspection platforms. (authors)

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DOE OSTI2022

Trace Crawler SOFTWARE

The trace crawler is a tool for selective web crawling to archive web resources with well-defined boundaries. The specific web navigation steps (or trace) are formulated for the families of webpages, where layout or HTML structure can be similar but the content is different, for example, GitHub, Slideshare, blogs, etc. The trace is recorded in a json file format.

Balakireva, Lyudmila↗
DOE OSTI2019

R and DE Robotic Sensor Intern Team: Sensor Suite Mock Up Testing

Assess sensor suite performance: - Mounted on crawler typical to what would be used in tunnel; - In test bed simulating the tunnel environment. The SuperDroid fiber tethered LT-F crawler is a general-purpose surveillance robot that our team has refurbished as a testing platform for the sensor suite. This crawler was selected because its dimensions are similar to the actual crawler that will be deployed in the field. Crawler preparation included: - Communicating with vendor to resolve software and platform issues; - Configuring a laptop with the crawler control software; - Reconfiguration of communication protocol between computer and crawler; - Resolution of control board checksum errors; - Installation of a mounting fixture on the base; - In progress: addition of lighting needed for total darkness. A solution for hosting the selected sensors onto a single unit that could function standalone or be mounted on the crawler was needed. Sensor mount requirements included: - Host Lidar, panospheric cameras and IMU sensors; - Cable management for rotating Lidar; - House on-board crawler computer; - Method for affixing to crawler; - Robust and vibration proof. The Lidar sensor required a sturdy mount that ensured the axis of rotation be centered with the LiDAR's desired laser path and included a slender profile in order to not block the scanning FOV. The mounting plate holds two 180-degree cameras on either side and the servo on the center. The servo mount is located so the axis of rotation is in the center of the plate. The mount features a set of guides that hold the wires and ensure they wrap around the spool area properly. The sensor box design features thick walls for added strength, holes for mounting the sensor suite to the crawler, notches on the bottom for the different components and holes for cable routing and management. The sensor mounts were designed using CREO and printed in the R and DE Additive Manufacturing Lab. To test the performance of the sensor suite for our application it was desired to design and build a test bed simulating the H-Canyon tunnel environment. Requirements included: - Dimensions similar to the tunnel; - Wall surfaces simulating the eroded tunnel walls; - Complete darkness; - Even and uneven crawler path; - Ability to change the tunnel width to simulate erosion. The HCAEX tunnel changes in height and includes several bends ranging from approximately 30 to 80 degrees, for that reason a test bed capable of easily being changed was needed. The final design includes two sections that can be connected to provide a 16' tunnel or placed at an angle to create a tunnel bend. The test bed features caster wheels for easy movement and has a sliding inner wall that enables tunnel width to be controlled. In order to simulate the tunnel walls without adding a lot of weight to the test bed, sheets of faux stone are to be used on the inner walls. To create a completely dark tunnel, 100% black-out film will be draped over the tunnel structure. Carpet remnants in the lab will enable folds to be introduced in the floor to generate uneven surface data.

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DOE OSTI2013

Design Optimization of Innovative High-Level Waste Pipeline Unplugging Technologies - 13341

Florida International University (FIU) is currently working on the development and optimization of two innovative pipeline unplugging methods: the asynchronous pulsing system (APS) and the peristaltic crawler system (PCS). Experiments were conducted on the APS to determine how air in the pipeline influences the system's performance as well as determine the effectiveness of air mitigation techniques in a pipeline. The results obtained during the experimental phase of the project, including data from pipeline pressure pulse tests along with air bubble compression tests are presented. Single-cycle pulse amplification caused by a fast-acting cylinder piston pump in 21.8, 30.5, and 43.6 m pipelines were evaluated. Experiments were conducted on fully flooded pipelines as well as pipelines that contained various amounts of air to evaluate the system's performance when air is present in the pipeline. Also presented are details of the improvements implemented to the third generation crawler system (PCS). The improvements include the redesign of the rims of the unit to accommodate a camera system that provides visual feedback of the conditions inside the pipeline. Visual feedback allows the crawler to be used as a pipeline unplugging and inspection tool. Tests conducted previously demonstrated a significant reduction of the crawler speed with increasing length of tether. Current improvements include the positioning of a pneumatic valve manifold system that is located in close proximity to the crawler, rendering tether length independent of crawler speed. Additional improvements to increase the crawler's speed were also investigated and presented. Descriptions of the test beds, which were designed to emulate possible scenarios present on the Department of Energy (DOE) pipelines, are presented. Finally, conclusions and recommendations for the systems are provided. (authors)

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DOE OSTI2018

H-Canyon Ventilation System Exhaust Tunnel Inspection at the Savannah River Site - 18052

The Department of Energy (DOE) H-Canyon Facility at the Savannah River Site (SRS) is operated by Savannah River Nuclear Solutions (SRNS). The Facility Structural Integrity Program (SIP) performs periodic visual inspections to confirm the component is capable of performing its safety function. This Program provides the process to document the conditions of safety related structural systems and components, their damage mechanisms, and recommend repairs if required before there is impact on the safety envelope. The H-Canyon Exhaust Tunnel is part of the H-Canyon Exhaust Ventilation System and is periodically inspected under the Structural Integrity Program. The Tunnel performs a Safety Class passive design feature function that is available 100% of the time. The Tunnel directs Canyon process air from the Canyon to the Sand Filter System. The radiological and chemical airborne activity coupled with the physical configuration of the tunnel precludes a manned entry into the tunnel. Tunnel inspections have been performed using cameras on a stick, referred to as pole cameras prior to CY2003. Since CY2003, five camera equipped crawlers have been used with varying levels of inspection success. With each successive crawler inspection, expectations have increased to perform tasks beyond visual examinations. The 2017 crawler performed the visual inspection but also included improvements on crawler performance, such as testing the use of wireless capability and remediation of crawler travel route, to the addition of stationary cameras and lighting at key locations. The latest 2017 crawler successfully traveled the entire length of the tunnel between the Canyon and Sand Filter System for the second time since development, thus providing key visual data for the integrity program [2]. In addition, several access ports were installed in 2017 following the removal of concrete core samples that allow for new visual inspection of the Canyon Crossover tunnel, thus providing information for an area that was generally inaccessible for monitoring. Planning for the 2019 crawler inspection is underway with the expectations to improve upon inspection cameras and also introduce mapping technologies such as LIDAR. The challenge to obtain meaningful data from the remote inspections of a 60+ year operating Canyon Exhaust tunnel continues to be a complex endeavor requiring close coordination of multiple organizations, adherence to Conduct of Operations, Radiological Safety, Worker Safety, etc. principles as well as alignment with Facility Safety Basis requirements. This paper discusses the continuing improvements in inspection techniques and the challenges associated these inspections. (authors)

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DOE OSTI2019

H-Canyon Tunnel Inspection System

Cable Analysis: The crawlers is controlled remotely via a long coax cable. In order to make sure we do not damage the cable which could cut our contact (data/power/control), we had to determine the bend radius of it at certain locations. This was done with dimensional analysis in Creo and inputting the information into a MATLAB program. Engineering Drawings: Since many of the crawlers parts, such as the main body, needed to be machined, part drawings were needed to communicate the details necessary for manufacture. Project Overview: The H-Canyon Ventilation Exhaust Tunnel due both to its long service history and exposure to aggressive process offgas chemistry has experienced degradation. In order to allow visual inspection of the condition of the radioactively-contaminated tunnel, a remote crawler was designed to deliver cameras as needed to return high definition video. My involvement included Vendor Searches, Cable Analysis, Thermal Analysis, and Engineering Drawings. Thermal Analysis: In order to see if internal active cooling is needed for the crawler, simplified thermal models were designed to approximate the internal temperatures: Conduction (assumes all heat sources are thermally-coupled to the crawler body); Convection (assumes no heat sources are thermally-bonded to crawler). Going Forward: Continue refining the cable analysis as the crawler model is updated and refined. Use my knowledge gained here to further my skills in engineering.

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DOE OSTI2025

Exploiting Trap Type and Color for Monitoring Macadamia Felted Coccid Acanthococcus ironsidei (Williams) and Associated Parasitic Wasps in Macadamia Orchards in Hawai’i

Acanthococcus ironsidei (Williams) (Hemiptera: Eriococcidae) is an invasive pest of macadamia, Macadamia integrifolia, in Hawai’i, causing death to macadamia trees and decreased nut productivity. Monitoring relies on wrapping double-sided sticky tapes over tree branches to trap dispersing crawlers (i.e., mobile immature stage), but this is tedious for growers, especially in large orchards. From September to November 2022 and December 2022 to February 2023, at two commercial macadamia orchards on Hawai’i Island, the use of colored sticky cards was assessed for improving the monitoring of A. ironsidei and to investigate the Hymenopteran parasitoid complex that inhabits macadamia canopies. At each study site, four different colored sticky cards (yellow, lime green, dark green, and white) were placed on the lower canopy of five trees, and on each tree, a transparent double-sided sticky tape was deployed. At bi-weekly intervals, the sticky cards were replaced and re-randomized on each tree, and the double-sided sticky tapes were replaced. The results showed that the sticky cards captured both A. ironsidei crawlers and (winged) male adults, while the double-sided sticky tapes captured only crawlers. The trap color did not have significant effects on the captures of A. ironsidei male adults at the sites, while the captures of crawlers on sticky cards were lowest on the dark green sticky traps at one site. The captures of A. ironsidei adult males on white sticky traps were generally correlated with the number of crawlers captured on the double-sided sticky tapes. The parasitoid complex captured had disparities in the attraction to color; however, the yellow, lime green and dark green colors were seemingly more effective for monitoring Encarsia lounsburyi (Berlese & Paoli), a reported parasitoid of A. ironsidei. These results have useful practical implications for improved monitoring of A. ironsidei crawlers, male adults and associated natural enemies.

Entomology↗
DOE OSTI2016

Development of Inspection Tools for the AY-102 Double-Shell Tank at the Hanford DOE Site - 16383

Florida International University (FIU) has been developing inspection tools to assist in identifying the location of the leak in the primary tank of AY-102. This effort has led to the development of a magnetic miniature rover and a pneumatic pipe crawler. The rover will travel through the refractory cooling channels and the crawler will travel through the air supply lines to the central plenum underneath the primary tank. Both tools will provide visual feedback and potentially identify the location of the leak. The magnetic miniature tool is a remote controlled rover with four wheels driven by independent micro DC motors. The rover will have to navigate through over 40 feet of channel that vary in width from 1.5 to 3.0 inches with four 90 deg. turns to reach the center of the tank. To avoid debris in the channel, the device will travel upside down magnetically attached to the bottom of the primary tank. The pneumatic pipe crawler is a worm type robot with a modular design, composed of interchangeable cylindrical modules connected with flexible links. The design is an evolution of previous peristaltic crawlers developed at FIU, and uses pneumatic actuators to emulate the contractions of the peristaltic movement. The crawler must travel approximately 100 feet through three and four inch piping and traverse through vertical risers, elbows and reducers to reach the central plenum. Prototypes for both the rover and the crawler have been designed and manufactured. Initial bench scale testing has validated the design concepts, demonstrating their ability to navigate through complex geometries. Future work will include full scale testing and evaluation of the systems' reliability. (authors)

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DOE OSTI2015

241-AY-102 Leak detection pit drain line visual inspection - 15678

In October 2012, Washington River Protection Solutions LLC (WRPS) determined that waste had leaked into the annulus of Tank 241-AY-102. WRPS conducted an extensive review of Tank AY-102 and increased both inspection and monitoring of the tank; however, the precise cause and location of the leak could not be determined. In parallel with the leak in the primary tank, the Tank AY-102 leak detection pit (LDP) was accumulating water through the drain system external to the secondary tank liner. Liquid collecting in the LDP is suspected to be from water intrusion and collects at a rate such that the LDP must be pumped routinely. Following a routine pumping event on June 20, 2013, elevated radiation dose rates were noted on the transfer hose and surface contamination readings were found on the transfer pump when it was removed from the Tank AY-102 LDP. These two field readings suggested that tank waste from a secondary liner breach could be leaking into the LDP. As a result, WRPS initiated a plan to ascertain the integrity of the secondary tank liner including a robotic inspection of the LDP. To perform the robotic visual inspection, a custom robotic crawler with a deployment device was designed, built, and operated by IHI Southwest for WRPS to inspect the 6 in (152 mm) leak detection pit drain line. To ensure success when deployed in the field, the inspection equipment was demonstrated at both the IHI facility in Denver, Colorado, and the Hanford Site using full scale piping mockups. On November 20, 2013 WRPS inspected the 6 in (152 mm) diameter drain line. The deployment device successfully attached to the drain line, and the crawler entered the drain line and traversed to within approximately 7 ft (2.1 m) of the central sump located under the center of the tank before losing traction. Crawler performance was satisfactory, and the quality of the camera image and lighting provided sufficient detail to document the current condition of the visible regions of the pipe. The inspection showed that the majority of the drain line was dry. Two wet areas were observed, a portion of the line nearest the LDP and a portion near the center of the tank. The portion nearest the LDP was under water prior to pumping on November 14, 2013. Although sediment and debris were seen during the inspection, it is believed to be construction debris and corrosion products. No material was found in the inspection that looked like tank waste or the material seen in the Tank AY-102 annulus (i.e., no greenish or yellowish deposits or dark fluids, dried salt deposits, or crystalline material). The contamination levels seen on the crawler were consistent with past values seen on LDP pumping equipment. Sampling and analysis of the recovered residues from the crawlers did not find material consistent with tank waste. (authors)

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DOE OSTI2020

Inspection Tools for Hanford Tanks and Waste Transport Systems - 20444

Recent integrity issues in the double-shell tanks (DST) at Hanford have motivated the need for developing innovative tools that can provide information regarding the health of the tanks. These issues include the primary linear failure of AY-102 and recent concerns of thinning in the DST secondary liners. Other concerns include erosion or corrosion on transfer lines and processing pipes. In recent years, Florida International University (FIU) has supported DOE-EM by developing tools that can assist in understanding the health of tanks and waste transport system at Hanford. More specifically, FIU has developed a miniature rover that can be deployed through small risers and gain access to refractory slots in the Hanford DSTs. It traverses through the slots on the primary liner upside down via magnets to avoid debris in the slots. Recent modifications include a spring loaded magnetic arm that allows the unit to traverse over large weld seams but does not reduce the overall functionality of the system. The system has also incorporated a control capsule that will sit within the annulus of the tank and improves on issues related to signal and voltage loss over long tether lines. Lastly, the unit is also being augmented with a second module that will include a means to prep the tank surface and obtain a thickness measurement using a dual element ultrasonic sensor. FIU has also developed a 6-inch peristaltic pipe crawler that operates similar to the previous pipe crawlers developed at FIU. This crawler is a marsupial type crawler that will navigate through the 6-inch drain lines, and deploy a small rover at the entrance of the drain slots. This rover will also traverse upside down on the secondary liner and provide information regarding the health of the liner. An initial prototype for the crawler unit has been developed, assembled and tested. The system is pneumatic and consists of three modules - two grippers and one extender. The validation tests are conducted in a mockup of the drain lines and demonstrate the system's ability to navigate through long pipe lengths and elbows. In this paper, a general overview of each of the aforementioned systems is presented along with results from testing and demonstrations that shows the applicability of each system. (authors)

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