754 research outputs found

    Mobile parallel manipulator consisting of two nonholonomic carts and their path planning

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    Mobile manipulators are widely used to transport and manipulate objects in industrial settings. In this paper, we propose a mobile manipulator that consists of a parallel mechanism and two two-wheel-drive carts. The planar motions of the carts are transmitted to a platform through three screw pairs of the parallel mechanism, allowing the pose of the platform to be controlled by only four motors. Kinematic analysis for such a two-cart mobile manipulator gives a Jacobian matrix, reveals the effects of nonholonomic constraints, and demonstrates that the yaw angle of the platform must be limited to avoid singular and failure configurations, and that the pitch angle is quite sensitive to uncertainties. Based on these analysis results, we present a custom path planning method for the carts. This method provides a non-optimal but easily realizable path planning algorithm with low computational cost, since the complex constraint conditions of this two-cart mobile manipulator have little influence on the proposed path generation process. The path planning process consists of four steps. We describe the motions of the carts in each step and establish a path tracking control system for the carts. Some simulations are conducted to show the motions of the carts, investigate the changes in the pose of the platform, and quantitatively evaluate the sensitivity of the platform’s pitch angle. Moreover, we construct an experimental prototype and conduct experiments to verify the validity and usefulness of the proposed mechanism and path planning method

    Analysis of automatic guided vehicles and self-guided vehicles for hospital foodservice

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    This thesis analyzes the relative merits of Automatic Guided Vehicles (AGVs) and Self Guided Vehicles (SGVs) in the area of hospital foodservice; Data is derived from the bids of Apogee Robotics for their Orbiter{dollar}\sp{\rm TM}{dollar} system (AGV) and Transitions Research Corp for the HelpMate{dollar}\sp{\rm TM}{dollar} self guided robot, to Humana Hospital Sunrise. The major difference between the two systems is that the AGV can carry a full Dietary cart with thirty trays but is limited to a pre-laid track system. Conversely HelpMate has a map of the facility programmed in its memory and can roam anywhere, but is only able to carry four trays; Final system recommendations are based on these bids and other data and a conclusion is made to lease/purchase the Helpmate self guided vehicle. A social history of the confrontation between men and machines is included

    "The Shift from Belt Conveyor Line to Work-cell Based Assembly Systems to Cope with Increasing Demand Variation and Fluctuation in The Japanese Electronics Industries"

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    As consumption patterns become increasingly sophisticated and manufacturers strive to improve their competitiveness, not only offering higher quality at competitive costs, but also by providing broader mix of products, and keeping it attractive by launching successively new products, the turbulence in the markets has intensified. This has impelled leading manufacturers to search the development of alternative production systems supposed to enable them operate more responsively. This paper discusses the trend of abandoning the strategy of relying on factory automation technologies and conveyor-based assembly lines, and shifting towards more human-centered production systems based on autonomous work-cells, observed in some industries in Japan (e.g. consumer electronics, computers, printers) since mid-1990s. The purpose of this study is to investigate this trend which is seemingly uneconomic to manufacturers established in a country where labor costs are among the highest in the world, so as to contribute in the elucidation of its background and rationality. This work starts with a theoretical review linking the need to cope with nowadays' market turbulence with the issue of nurturing more agile organizations. Then, a general view of the diffusion trend of work-cell based assembly systems in Japanese electronics industries is presented, and some empirical facts gathered in field studies conducted in Japan are discussed. It is worthy mentioning that the abandonment of short cycle-time tasks performed along conveyor lines and the organization of workforce around work-cells do not imply a rejection of the lean production paradigm and its distinctive process improvement approach. High man-hour productivity is realized as a key goal to justify the implementation of work-cells usually devised to run in longer cycle-time, and the moves towards this direction has been strikingly influenced by the kaizen philosophy and techniques that underline typical initiatives of lean production system implementation. Finally, it speculates that even though the subject trend is finding wide diffusion in the considered industries, it should not be regarded as a panacea. In industries such as manufacturing of autoparts, despite the notable product diversification observed in the automobile market, its circumstances have still allowed the firms to rely on capital-intensive process, and this has sustained the development of advanced manufacturing technologies that enable the agile implementation and re-configuration of highly automated assembly lines.

    Automation and robotics human performance

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    The scope of this report is limited to the following: (1) assessing the feasibility of the assumptions for crew productivity during the intra-vehicular activities and extra-vehicular activities; (2) estimating the appropriate level of automation and robotics to accomplish balanced man-machine, cost-effective operations in space; (3) identifying areas where conceptually different approaches to the use of people and machines can leverage the benefits of the scenarios; and (4) recommending modifications to scenarios or developing new scenarios that will improve the expected benefits. The FY89 special assessments are grouped into the five categories shown in the report. The high level system analyses for Automation & Robotics (A&R) and Human Performance (HP) were performed under the Case Studies Technology Assessment category, whereas the detailed analyses for the critical systems and high leverage development areas were performed under the appropriate operations categories (In-Space Vehicle Operations or Planetary Surface Operations). The analysis activities planned for the Science Operations technology areas were deferred to FY90 studies. The remaining activities such as analytic tool development, graphics/video demonstrations and intelligent communicating systems software architecture were performed under the Simulation & Validations category

    M.I.N.G., Mars Investment for a New Generation: Robotic construction of a permanently manned Mars base

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    A basic procedure for robotically constructing a manned Mars base is outlined. The research procedure was divided into three areas: environment, robotics, and habitat. The base as designed will consist of these components: two power plants, communication facilities, a habitat complex, and a hangar, a garage, recreation and manufacturing facilities. The power plants will be self-contained nuclear fission reactors placed approx. 1 km from the base for safety considerations. The base communication system will use a combination of orbiting satellites and surface relay stations. This system is necessary for robotic contact with Phobos and any future communication requirements. The habitat complex will consist of six self-contained modules: core, biosphere, science, living quarters, galley/storage, and a sick bay which will be brought from Phobos. The complex will be set into an excavated hole and covered with approximately 0.5 m of sandbags to provide radiation protection for the astronauts. The recreation, hangar, garage, and manufacturing facilities will each be transformed from the four one-way landers. The complete complex will be built by autonomous, artificially intelligent robots. Robots incorporated into the design are as follows: Large Modular Construction Robots with detachable arms capable of large scale construction activities; Small Maneuverable Robotic Servicers capable of performing delicate tasks normally requiring a suited astronaut; and a trailer vehicle with modular type attachments to complete specific tasks; and finally, Mobile Autonomous Rechargeable Transporters capable of transferring air and water from the manufacturing facility to the habitat complex

    Behavior-based Control for Service Robots inspired by Human Motion Patterns : a Robotic Shopping Assistant

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    Es wurde, unter Verwendung menschenähnlicher Bewegungsmuster und eines verhaltensbasierten Ansatzes, eine Steuerung für mobile Serviceroboter entwickelt, die Aufgabenplanung, globale und lokale Navigation in dynamischen Umgebungen, sowie die gemeinsame Aufgabenausführung mit einem Benutzer umfasst. Das Verhaltensnetzwerk besteht aus Modulen mit voneinander unabhängigen Aufgaben. Das komplexe Gesamtverhalten des Systems ergibt sich durch die Vereinigung der Einzelverhalten (\u27Emergenz\u27)

    Service Robots for Hospitals:Key Technical issues

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    AN INTERNET OF THINGS–BASED APPROACH TO INNOVATE CANTEEN STORES DEPARTMENT’S RETAIL OPERATIONS

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    In a competitive business environment, retail organizations in the Western world are capitalizing on technological tools and solutions to enhance customer experience and boost sales. Specifically, retailers that adopt Internet of Things (IoT) technologies improve customer experience and achieve cost savings. Yet such innovation is rare outside the Western world. Hence, early adopters of IoT technologies in retail operations in Pakistan could gain a competitive advantage. This study aims to create a deeper understanding of how Pakistan-based Canteen Stores Department (CSD), a retail chain mainly serving service members and their families, can use IoT technologies to significantly modernize and improve its operations and distinguish itself from competitors. To do so, this study conducts a qualitative analysis of scholarly articles on the relevant technologies and on IoT-based products offered by commercial companies. The authors also include findings from discussions with CSD customers and management. The results of the study indicate CSD can use IoT technologies to optimize store layout, offer interactive in-store mapping, automate checkout systems, implement smart shelving and digital price tagging, improve in-store promotions, enhance customer relationship management, and modernize distribution, transportation, and warehousing. The study also offers CSD management guidance on how to implement IoT technologies into retail operations at one location as a pilot.Outstanding ThesisLieutenant Commander, Pakistan NavyWing Commander, Pakistan Air ForceLieutenant Colonel, Pakistan ArmyApproved for public release. Distribution is unlimited

    Situation Assessment for Mobile Robots

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