This technical note illustrates that some of the differences that have been reported regarding wheelchair propulsion may be due to the methods used to calculate key variables. Wheelchair ambulation is a very important form of locomotion that lacks a standard pushrim force and moment analysis system. We have developed tools for analyzing upper limb biomechanics during manual wheelchair propulsio...

Generating propulsion with small-scale devices is a major challenge due to both the domination of viscous forces at low Reynolds numbers as well as the small relative stroke length of traditional actuators. Ferromagnetic shape memory materials are good candidates for such devices as they exhibit a unique combination of large strains and fast responses, and can be remotely activated by magnetic ...

The objective of this study was to explore the joint kinetics of upper extremities during wheelchair maneuvers. A high incidence of musculoskeletal injuries has been reported due to the overuse and high repetitive motion of wrist, elbow and shoulder during wheelchair propulsion. Studies have been conducted with the use of a dynamometer or treadmill to simulate propulsion on level or inclined su...

This paper discusses pre-design and integration considerations involved when implementing distributed propulsion for future aircraft concepts. In this context, distributed propulsion is achieved by utilization of multiple or a single (large) fan. The distributed integration of the propulsion system leads to strong coupling between airframe aerodynamics and motive power performance, which is add...

Objective. To compare the energy expenditure of two types of manual wheelchair propulsion. Design. Experimental and comparative design using matched controls. Background. A new manual wheelchair propulsion technique is proposed to minimize the overload exerted on the upper limb during the classical propulsion. The energy cost and other parameters of this new propulsion technique were evaluated....

This paper identifies breakpoints for various power and propulsion technologies, with a special focus on fission-based sources in support of NASA’s Mars exploration program. Transportation, orbital, and surface missions are addressed through an assessment architecture developed for this study. This architecture is based on three key considerations: decomposition of generic Mars missions into ph...

This paper addresses modeling and kinematic analysis of a serial-parallel structure-variable field robot which based on double spirals. Although a few researchers have studied on spiral propulsion mechanism, it is observed in our previous work that the spiral can move forward between gaps of plants and damages to the plants are very little. It can be used to carry measurement devices on investi...

Current interest in advanced propulsion within NASA and research activities in advanced propulsion concepts at the Jet Propulsion Laboratory are reviewed. The concepts,which include high power plasma thrusters such as lithiun~-fueled Lorentz-Force-Accelerators,MEMS-scale propulsion systems, in-situ propellant utilization techniques, fusion propulsion systems and methods of using antimatter, off...

In this paper, an overview of the techniques applied to AC electric propulsion field has been done. Actual study cases of electric ship propulsion schemes are considered. An impartial comparison between three-level converters versus two-level converter from the viewpoint of electric ship propulsion requirements has been done. Diodeclamped three-level converters using direct torque control (DTC)...

The objective was to conduct a methodological pilot study to analyze wheelchair propulsion upper limb kinematics in standard competitive play considering the functional classification of each athlete. Ten basketball players with a functional classification ranging from 1 to 4 were included in the study. Four camcorders (Kinescan-IBV) and a treadmill for wheelchairs were used. Temporal parameter...