Safe Supervisory Control of Soft Robot Actuators

Although soft robots show safer interactions with their environment than traditional robots, soft mechanisms and actuators still have significant potential for damage or degradation particularly during unmodeled contact. This article introduces a feedback strategy for safe soft actuator operation during control of a soft robot. To do so, a supervisory controller monitors actuator state and dynamically saturates control inputs to avoid conditions that could lead to physical damage. We prove that, under certain conditions, the supervisory controller is stable and verifiably safe. We then demonstrate completely onboard operation of the supervisory controller using a soft thermally-actuated robot limb with embedded shape memory alloy (SMA) actuators and sensing. Tests performed with the supervisor verify its theoretical properties and show stabilization of the robot limb's pose in free space. Finally, experiments show that our approach prevents overheating during contact (including environmental constraints and human contact) or when infeasible motions are commanded. This supervisory controller, and its ability to be executed with completely onboard sensing, has the potential to make soft robot actuators reliable enough for practical use

The relationships between nurse care, attitude of patient and nurse with cancer patient satisfaction

This study investigates the relationships between nurse care, attitude of patient and nurse with cancer patient satisfaction using the quantitative methodology. In Libya, the challenge of medical facilities and treatment is a current issue. Thus, this study was conducted to investigate the patients’ satisfaction at National Cancer Institute Misurata, Libya. The participants were 217 cancer patients of National Institute of Oncology located in Misurata, Libya. The study scale was adopted and adapted from that used by previous researchers to measure nurse care, nurse attitude, patient attitude, hospital service quality and patient satisfaction on a 5-point Likert scale. The nurse care, nurse attitude and patient attitude are independent variables and cancer patient satisfaction is the dependent variable in this study. On the other hand, hospital service quality and patient characteristic are control variables. SPSS software was used to analyses the data collected. The analyses of this study included descriptive statistic, correlation analysis and multiple regression analysis. The study found that on the overall basis, there is a significant statistical relationship between nurse care and cancer patient satisfaction, and there is a significant statistical relationship between attitude and cancer patient satisfaction. The sub-hypotheses show that there are no a relationship between interpersonal skills of nurse care and efficiency of nurse care with cancer patient satisfaction which suggest there might be interactions between these variables. Result also shows that for the sub-hypotheses, only patient attitude and cancer patient satisfaction indicated significant relationship, while there is no significant relationship between nurse attitude and patient satisfaction. This also indicates of possible interactions between the variables. On an overall basis, it can be concluded that to increase in the satisfaction level cancer patient, the management do it by focusing on improving the level of nurse care, nurse attitude and patient attitude

Feasibility of remotely manipulated welding in space. A step in the development of novel joining technologies

In order to establish permanent human presence in space technologies of constructing and repairing space stations and other space structures must be developed. Most construction jobs are performed on earth and the fabricated modules will then be delivered to space by the Space Shuttle. Only limited final assembly jobs, which are primarily mechanical fastening, will be performed on site in space. Such fabrication plans, however, limit the designs of these structures, because each module must fit inside the transport vehicle and must withstand launching stresses which are considerably high. Large-scale utilization of space necessitates more extensive construction work on site. Furthermore, continuous operations of space stations and other structures require maintenance and repairs of structural components as well as of tools and equipment on these space structures. Metal joining technologies, and especially high-quality welding, in space need developing

USM Mini Remotely Operated Vehicle: Vehicle Development & Integration.

This paper describes the development of vehicle design and hardware integration of the Mini remotely Operated Vehicle developed by members of USM Robotics Research Group

The 1981 NASA/ASEE Summer Faculty Fellowship Program: Research reports

Research reports related to spacecraft industry technological advances, requirements, and applications were considered. Some of the topic areas addressed were: (1) Fabrication, evaluation, and use of high performance composites and ceramics, (2) antenna designs, (3) electronics and microcomputer applications and mathematical modeling and programming techniques, (4) design, fabrication, and failure detection methods for structural materials, components, and total systems, and (5) chemical studies of bindary organic mixtures and polymer synthesis. Space environment parameters were also discussed

Development of a Ceramic Foam Filter for Filtering Molten Aluminum Alloy in Casting Processes

Metal casting component are found in 90 percent of manufactured goods and equipment, from critical components for aircraft and automotive industry to home applications. However, molten metal used to produce metal casting in practice generally contains impurities and inclusions which are deleterious to final cast metal product. Currently, filtration technique by using ceramic foam filter has been accepted as a successful method of reducing inclusions from molten metal during the casting of metal parts. The present research has been done to fabricate and improve a ceramic foam filter for using in filtration of molten metal, especially aluminium based alloys. It is an objective of the present innovation to provide a ceramic foam filter characterized by cost of raw materials. Ceramic foam filters are produced by impregnating polyurethane foam with ceramic slurry, drying, baking and finally firing the foam in the oven. Experimental tests were carried out to the filters to measure dimensions, weight, cold compression strength, and permeability properties before pouring process. After pouring process, the filter was cut into several sections to measure the macro and microstructure of the filter and ensure that impurity particles captured by a filter. Thermal shock properties, obtained from pouring liquid aluminium when filter was placed in the gating system to ensure that the filters could withstand temperatures of aluminium alloys. Further experiments were carried out to investigate and determine the efficiency of produced ceramic foam filter on quality of cast products. The result obtained in this investigation, the mechanical properties for aluminum LM6 alloy sand casting increased when ceramic foam filter was inserted into the gating system. A produced filter by using new materials is economical to be produced. Further more, the analysis data shows present innovation filter which can be made in any shape and size, has excellent thermal shock resistance, adequate compressive strength, acceptable density and permeability properties

The United States Specialty Steel Industry

Part I of this note briefly describes the problems of the specialty steel industry and traces the attempts to deal with those problems from 1968 through the imposition of the relief measures which spawned the current negotiations. After discussing the trade history of the specialty steel industry, the note examines the effectiveness of two domestic import relief statutes through which the government has attempted to assist the industry. The note then analyzes U.S. attempts to aid the specialty steel industry through measures which violate the fundamental principles of the GATT system. The note concludes that since the GATT system cannot effectively handle the problems of the specialty steel industry, the U.S. should lobby for the formation of a new international system to govern the specialty steel industry similar to that within which the textile industry now operates

Considerations Regarding Graduate Student Persistence

Completion of graduate studies is a central issue for universities. Over the past decade researchers interested in higher education have become concerned with graduate student completion rates. Possible reasons underlying variations in graduate student persistence have included the amassed learning experiences and subsequent perceptions of graduate students, supervisory committee members, and other department staff. This article addresses some of the psychosocial considerations that underlie the complex interactions among students, supervisory committees, and departmental support staff, referred to here as the "academic triad." Using Seligman's (1991) explanatory framework and Bandura's (1986) self-efficacy theory, this article explains how student persistence is closely tied to the behavior of students, academics, and departmental support staff. Further, the article provides two frameworks to gain a broadened understanding of the relationship between the academic triad and graduate student persistence. Recommendations are provided as to how to foster graduate student persistence through improved personal and interpersonal reflexivity.L'obtention par les étudiants d'un diplôme de deuxième ou troisième cycle constitue une question centrale pour les universités. Depuis les dix dernières années, les chercheurs dans le domaine de l'éducation postsecondaire se penchent davantage sur les taux de réussite chez les étudiants du deuxième ou troisième cycle. Parmi les raisons évoquées pour expliquer la variation dans la persévérance des étudiants du deuxième ou troisième cycle, on a proposé trois facteurs: l'accumulation des expériences d'apprentissage et les perceptions qu'en ont les étudiants, les membres du comité de thèse et finalement, les membres du personnel non-académique des départements impliqués. Cet article étudie quelques-unes des considérations psychosociales qui sous-tendent les interactions complexes entre les étudiants, les comités de thèse et le personnel non-académique. On nomme ces trois groupes la «triade académique». En s'appuyant à la fois sur le cadre de Seligman (1991) et la théorie d'auto efficacité de Bandura (1986), les auteurs expliquent le lien serré entre la persévérance des étudiants d'une part et le comportement des étudiants, du personnel académique et du personnel non-académique d'autre part. Les auteurs fournissent en plus deux cadres permettant de mieux comprendre le rapport entre la triade académique et la persévérance des étudiants de deuxième ou troisième cycle. Sont également présentées des recommandations pour favoriser la persévérance des étudiants de deuxième ou troisième cycle par le biais d'une autoréférence personnelle et interpersonnelle améliorée