1,986 research outputs found

    Evaluating the Radiation Tolerance of a Robotic Finger

    Get PDF
    In 2024, The Large Hadron Collider (LHC) at CERN will be upgraded to increase its luminosity by a factor of 10 (HL-LHC). The ATLAS inner detector (ITk) will be upgraded at the same time. It has suffered the most radiation damage, as it is the section closest to the beamline, and the particle collisions. Due to the risk of excessive radiation doses, human intervention to decommission the inner detector will be restricted. Robotic systems are being developed to carry out the decommissioning and limit radiation exposure to personnel. In this paper, we present a study of the radiation tolerance of a robotic finger assessed in the Birmingham Cyclotron facility. The finger was part of the Shadow Grasper from Shadow Robot Company, which uses a set of Maxon DC motors

    Improving plan quality and consistency by standardization of dose constraints in prostate cancer patients treated with CyberKnife.

    Get PDF
    Treatment plans for prostate cancer patients undergoing stereotactic body radiation therapy (SBRT) are often challenging due to the proximity of organs at risk. Today, there are no objective criteria to determine whether an optimal treatment plan has been achieved, and physicians rely on their personal experience to evaluate the plan's quality. In this study, we propose a method for determining rectal and bladder dose constraints achievable for a given patient's anatomy. We expect that this method will improve the overall plan quality and consistency, and facilitate comparison of clinical outcomes across different institutions. The 3D proximity of the organs at risk to the target is quantified by means of the expansion-intersection volume (EIV), which is defined as the intersection volume between the target and the organ at risk expanded by 5 mm. We determine a relationship between EIV and relevant dosimetric parameters, such as the volume of bladder and rectum receiving 75% of the prescription dose (V75%). This relationship can be used to establish institution-specific criteria to guide the treatment planning and evaluation process. A database of 25 prostate patients treated with CyberKnife SBRT is used to validate this approach. There is a linear correlation between EIV and V75% of bladder and rectum, confirming that the dose delivered to rectum and bladder increases with increasing extension and proximity of these organs to the target. This information can be used during the planning stage to facilitate the plan optimization process, and to standardize plan quality and consistency. We have developed a method for determining customized dose constraints for prostate patients treated with robotic SBRT. Although the results are technology specific and based on the experience of a single institution, we expect that the application of this method by other institutions will result in improved standardization of clinical practice

    Measurements by A LEAP-Based Virtual Glove for the hand rehabilitation

    Get PDF
    Hand rehabilitation is fundamental after stroke or surgery. Traditional rehabilitation requires a therapist and implies high costs, stress for the patient, and subjective evaluation of the therapy effectiveness. Alternative approaches, based on mechanical and tracking-based gloves, can be really effective when used in virtual reality (VR) environments. Mechanical devices are often expensive, cumbersome, patient specific and hand specific, while tracking-based devices are not affected by these limitations but, especially if based on a single tracking sensor, could suffer from occlusions. In this paper, the implementation of a multi-sensors approach, the Virtual Glove (VG), based on the simultaneous use of two orthogonal LEAP motion controllers, is described. The VG is calibrated and static positioning measurements are compared with those collected with an accurate spatial positioning system. The positioning error is lower than 6 mm in a cylindrical region of interest of radius 10 cm and height 21 cm. Real-time hand tracking measurements are also performed, analysed and reported. Hand tracking measurements show that VG operated in real-time (60 fps), reduced occlusions, and managed two LEAP sensors correctly, without any temporal and spatial discontinuity when skipping from one sensor to the other. A video demonstrating the good performance of VG is also collected and presented in the Supplementary Materials. Results are promising but further work must be done to allow the calculation of the forces exerted by each finger when constrained by mechanical tools (e.g., peg-boards) and for reducing occlusions when grasping these tools. Although the VG is proposed for rehabilitation purposes, it could also be used for tele-operation of tools and robots, and for other VR applications

    Aerospace medicine and biology: A continuing bibliography with indexes (supplement 324)

    Get PDF
    This bibliography lists 200 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during May, 1989. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

    "Making Safety Happen" Through Probabilistic Risk Assessment at NASA

    Get PDF
    NASA is using Probabilistic Risk Assessment (PRA) as one of the tools in its Safety & Mission Assurance (S&MA) tool belt to identify and quantify risks associated with human spaceflight. This paper discusses some of the challenges and benefits associated with developing and using PRA for NASA human space programs. Some programs have entered operation prior to developing a PRA, while some have implemented PRA from the start of the program. It has been observed that the earlier a design change is made in the concept or design phase, the less impact it has on cost and schedule. Not finding risks until the operation phase yields much costlier design changes and major delays, which can result in discussions of just accepting the risk. Risk contributors identified by PRA are not just associated with hardware failures. They include but are not limited to crew fatality due to medical causes, the environment the vehicle and crew are exposed to, the software being used, and the reliability of the crew performing required actions. Some programs have entered operation prior to developing a PRA, and while PRA can still provide a benefit for operations and future design trades, the benefit of implementing PRA from the start of the program provides the added benefit of informing design and reducing risk early in program development. Currently, NASAs International Space Station (ISS) program is in its 20th year of on-orbit operations around the Earth and has several new programs in the design phase preparing to enter the operation phase all of which have active (or living) PRAs. These programs incorporate PRA as part of their Risk-Informed, Decision-Making (RIDM) process. For new NASA human spaceflight programs discussion begins with mission concept, establishing requirements, forming the PRA team, and continues through the design cycles into the operational phase. Several examples of PRA related applications and observed lessons are included

    Aerospace medicine and biology: A continuing bibliography with indexes, supplement 218, April 1981

    Get PDF
    This bibliography lists 161 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1981

    NASA space station automation: AI-based technology review

    Get PDF
    Research and Development projects in automation for the Space Station are discussed. Artificial Intelligence (AI) based automation technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics. AI technology will also be developed for the servicing of satellites at the Space Station, system monitoring and diagnosis, space manufacturing, and the assembly of large space structures

    NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 43)

    Get PDF
    Abstracts are provided for 128 patents and patent applications entered into the NASA scientific and technical information system during the period Jan. 1993 through Jun. 1993. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

    Aerospace Senior Design Project, In-Orbit Manufacturing Process of Electronic Enclosures

    Get PDF
    This report presents the final design of A-MOD\u27s groundbreaking in-orbit electronic enclosure manufacturing device. The detailed design, encompassing analysis, specifications, and component specifics, showcases the feasibility of the proposed system. With objectives met, the report navigates through the concept of operations, validation and verification processes, critical design of mechanical and electrical components, software integration, performance specifications, and a comprehensive risk assessment. A-MOD\u27s design revolutionizes space technology by proposing a device capable of manufacturing electronic enclosures in orbit, reducing costs and optimizing resources. Thorough validation and verification procedures ensure the system\u27s adherence to stringent requirements, covering precision, quality, thermal resilience, and power efficiency, providing confidence in the robustness of the design. The critical design section highlights the meticulous mechanical design, detailing overall dimensions, manufacturing head specifics, and material storage mechanisms supported by CAD models and simulations. Although secondary in focus, the electrical design section outlines essential aspects, emphasizing wiring, off-the-shelf electrical components, and microcontroller usage, contributing to the system\u27s overall efficiency. The performance specifications provide crucial metrics for evaluating efficiency in terms of mass, time, power consumption, and production quantity, with an enclosure test case serving as a benchmark for raw material optimization. The detailed risk assessment identifies potential challenges, emphasizing preventive actions and continuous testing and research, instilling confidence in the system\u27s reliability. In essence, A-MOD\u27s report offers a deep dive into groundbreaking space technology, presenting a design and a vision for the future of in-orbit manufacturing. The comprehensive insights and innovative solutions detailed in this report make it a must-read for space technology enthusiasts, researchers, and professionals seeking cutting-edge advancements in space manufacturing capabilities. The four most significant benefits of A-MOD\u27s design to society and potential customers are its cost efficiency, rapid prototyping capabilities, reduced environmental impact, and enhanced space exploration capabilities. These advantages collectively position the in-orbit electronic enclosure manufacturing device as a transformative technology with broad implications for the space industry and beyond

    Treatment planning study of cyberKnife prostate SBRT (stereotactic body radiation therapy) using CT-based vs MRI-based prostate volumes

    Full text link
    This study has been conducted for the purpose of investigating the systematic dose reduction of rectum and neurovascular bundles (NVBs) during treatment planning of the CyberKnifeTM prostate SBRT using CT-Based volumes versus MRI-based volumes. Three prostate cancer patients were Planned for the CyberKnifeTM prostate SBRT and they underwent computed tomography (CT) and magnetic resonance imaging (MRI) preplanning exams. The patients were positioned during both exams using an immobilizing device. A radiation oncologist and a radiologist delineated the prostate gland, intra-prostatic and peri-prostatic structures, and pelvic organs of interest in both CT and MRI images. The CT and MRI images were fused based on fuducial markers to accurately align the prostate. Radiation Therapy Oncology protocol RTOG 0938 was followed to meet the target volume (prostate plus margin) dose coverage requirement, and dose-volume constraints for organs at risk, including rectum, bladder, femoral heads, penile bulb, urethra, skin and NVBs. Radiation dose volume parameters were recorded for both volumes and compared. The preliminary result shows that the CT-based volumes were generally larger than MRI-based volumes of the prostate. Therefore, the CT-based volumes resulted in less accurate treatment planning and dose delivery to radiosensitive structures
    • …
    corecore