OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Microelectronics, Space Technology, Trusted AI and Autonomy, Nuclear OBJECTIVE: Develop a robotic system for leak location and repair of high-vacuum systems in cyclotrons and similar particle accelerators. DESCRIPTION: Particle accelerators such as cyclotrons form a crucial link in enabling microelectronics in hostile radiation environments. Few facilities are available for Heavy Ion Single Event Effect testing in particular, which causes a bottleneck in the fielding of space systems and other programs with radiation environment requirements. These facilities are aging and heavily tasked, leaving little time and few resources for invasive repairs. Impacts to availability from insufficient maintenance or downtime for extensive repairs threaten limited and inelastic supply of beam time at these facilities. A major contributor to maintenance issues is leaks in the high-vacuum systems of the accelerators. Leak locations are frequently buried underneath other sensitive assemblies and in tightly confined spaces, particularly in the Radio Frequency tank and acceleration region of the cyclotron. Finding the location of these leaks if often invasive to the sensitive system, time consuming, and unreliable. Once found, leaks are difficult to repair with lasting solutions due to the mentioned access difficulties. Radioactivity in the vacuum components due to accelerator operation further slows and complicates maintenance actions, while representing a hazard to personnel. An innovative solution is proposed in the development of a robotic system capable of locating and repairing leaks in the high-vacuum system with greater speed, accuracy, and durability than possible using current manual methods. Further benefits would include reduction in invasive maintenance to the sensitive facilities and reduction in radiation hazard to personnel. Feasible solutions would need to be able to operate in the radiation environment of the accelerator vacuum, navigate the small inner dimensions of the vacuum system, locate and image leaks in the predominately copper systems, weld or otherwise enact lasting repairs to the located leaks, and reliably self-extract from the vacuum system while leaving no debris and only trace gasses in the vacuum system. The vacuum system would not need to be evacuated during operation of the robotic system. Key parameters are prioritized as follows: Number of 90 degree bends the solution can tolerate for extraction after loss of robotic power or control Minimum diameter the solution can traverse Distance the solution can traverse through evacuated piping Efficacy of sensors for locating leaks. Minimum detectable leak flow rate, minimum leak length/width for detection, or similar metric. Ability to flag or map location of leaks without damage to vacuum system Ability to enact durable repairs on located leaks Estimated Total Ionizing Dose (TID) radiation tolerance of any non-exchangeable microelectronics, cabling, and material components inserted into the accelerator vacuum system. Any TID tolerance over 15 krad(SiO2) may be stated as over 15 krad(SiO2)' or similar language. PHASE I: Perform a feasibility study on a robotic system for leak location and repair of high-vacuum systems in cyclotrons and other particle accelerators. Blockage or damage to the accelerator vacuum system by the proposed solution would be unacceptable. Emphasis will be placed on ensuring full recovery of the robotic system from the accelerator vacuum system in case of loss of power or control. Overall goal is to maximize the percent by length of the accelerator vacuum system serviceable with leak location and, separately, repair; while remaining fully recoverable and without posing danger to the vacuum system. The Lawrence Berkeley National Laboratory (LBNL) 88-inch cyclotron will be used as the baseline case for evaluating success. The feasibility study shall: Describe a system capable of traversing a portion the vacuum system of the LBNL 88-inch cyclotron Describe recovery mechanism for the system under loss of robotic power or control Describe mechanisms for leak location Describe mechanisms for mapping or marking located leaks Describe mechanisms for durable repair of located leaks Analyze the described solution against the key parameters from the above description Provide a report including all all generated files (e.g., CAD drawings) and a program plan for system development PHASE II: Phase II will result in building, testing and delivering a fully functional prototype of the solution developed in phase I. Testing shall include trials on piping models with attention to the parameters described in the description above. The prototype shall demonstrate recovery under simulated power and control loss scenarios from mock piping models. The prototype shall demonstrate location of a simulated vacuum leak. The prototype shall demonstrate non-destructive marking or mapping of located leaks. The prototype shall demonstrate durable repair of simulated leaks. Only after trials and demonstrations on mock piping models may any test be conducted on accelerator vacuum systems. Demonstration on actual accelerator vacuum systems is the goal of phase II testing, however, any access to accelerator vacuum systems is entirely at the discretion of LBNL or other facility. PHASE III DUAL USE APPLICATIONS: Particle accelerator use is dominated by medical applications and scientific applications which outnumber and outspend the immediate DoD interest of Single Event Effect testing for microelectronics. Such facilities have similar vacuum systems and face similar challenges with their maintenance that could offer a market for robotic systems or services. Solutions to this proposal are also applicable to a wide variety of high vacuum facilities in various industries including advanced spectroscopy and microscopy, epitaxy growth and deposition facilities such as in the semiconductor industry, and science facilities such as gravitation wave detectors. REFERENCES: J. Benitez et al., 88-Inch Cyclotron Upgrades for Improved 20 MeV/nucleon Cocktail Beam Delivery, 2023 Single Event Effects Symposium & Military And Aerospace Programmable Logic Devices Combined Workshop, La Jolla, California, USA, 2023. M. K. Covo et al., "88-Inch Cyclotron: The one-stop facility for electronics radiation testing," 2017 IEEE International Workshop on Metrology for AeroSpace (MetroAeroSpace), Padua, Italy, 2017, pp. 484-488, doi: 10.1109/MetroAeroSpace.2017.7999622. KEYWORDS: Heavy Ion particle accelerators, cyclotron, Ultra-High Vacuum systems, Single Event Effects, Robotics, Leak repair
