This paper focuses on hydrodynamic modeling and control of spheroidal underwater vehicle. The vehicle considered in this is appendage free unstable. Water jet propulsion system used dynamics the highly unstable due to munk moment. shape robot nuclear reactor inspection, port security defence ocean surveillance where external appendages are not required. A new innovative technique, Sliding mode ...

The first definite interstellar object observed in our solar system was discovered October of 2017 and subsequently designated 1I/'Oumuamua. In addition to its extrasolar origin, observations analysis this indicate some unusual features which can only be explained by in-situ exploration. For purpose, various spacecraft intercept missions have been proposed. Their propulsion schemes chemical, ex...

High-speed permanent magnet synchronous machines are of great interest in the applications where high utilization factor and e ciency are required. Depending on application, power requirements change from kilowatts to megawatts. To investigate power limits of high-speed machines, the present feasibility study focuses on a 20 megawatt (MW) electric drive for marine propulsion. However, in additi...

This study aims at studying the reliability evaluation for the marine propulsion shaft system under the severe sea conditions. The variations of the contact stress between the bearings and the marine propulsion shaft under the severe sea conditions are analyzed using the finite element simulation. The stress-strength interference theory is used to evaluate the reliability of the marine propulsi...

Molybdenum alloys are excellent candidates for extremely high temperature environments, such as in nuclear thermal propulsion spaceflight systems. Spark plasma sintering is a useful manufacturing technique that allows rapid fabrication of refractory materials difficult to sinter using more traditional methods. Pre-alloyed molybdenum with 30 wt% tungsten powder was consolidated spark under varie...

A gold nanoshell-functionalized polymer multilayer nanorocket performs self-propulsion upon the irradiation with NIR light in the absence of chemical fuel. Theoretical simulations reveal that the NIR light-triggered self-thermophoresis drives the propulsion of the nanorocket. The nanorocket also displays -efficient NIR light-triggered propulsion in -biofluids and thus holds considerable promise...

This paper presents design modification to the existing standard wheelchair by incorporating an improved propulsion system and also braking and tilting systems that allow its full control with only one hand. The proposed design has the propulsion system with a chain drive powered through a four-bar linkage driven by the main handle. The desired direction of motion is obtained by moving the leve...

. Propulsion styles that are characterized by high stresses may influence the susceptibility of manual wheelchair users (MWCU) to upper limb injury. An experimental, crosssectional study was designed to compare physiological and biomechanical characteristics of wheelchair propulsion in two groups of MWCU—a trunk flexion propulsion style group (FG) and a non-trunk flexion propulsion style group ...

Since the introduction of large jet-powered transport aircraft, the majority of these vehicles have been designed by placing thrust-generating engines either under the wings or on the fuselage to minimize aerodynamic interactions on the vehicle operation. However, advances in computational and experimental tools along with new technologies in materials, structures, and aircraft controls, etc. a...

Objectives. To quantify the association between performance-based manual wheelchair propulsion tests (20 m propulsion test, slalom test, and 6 min propulsion test), trunk and upper extremity (U/E) strength, and seated reaching capability and to establish which ones of these variables best predict performance at these tests. Methods. 15 individuals with a spinal cord injury (SCI) performed the t...