Propulsion

About: Propulsion is a research topic. Over the lifetime, 24977 publications have been published within this topic receiving 200311 citations.

Running control device

Abstract: A running control device for a watercraft controls propulsion force and tilt angle of a propulsion device relative to the hull of the watercraft. The running control device also sets an optimum trim angle automatically. The running control device includes a propulsion force control section that controls the propulsion force of the propulsion device. The running control device also includes a tilt angle control section that controls the tilt angle of the propulsion device. A target propulsion force calculation module responds to first input information (e.g., watercraft velocity) to calculate a target propulsion force. An amount-of-operation calculation module responds to second input information to calculate an amount of operation of the propulsion device to produce the target propulsion force. The tilt angle control section includes a tilt angle calculation module that determines the tilt angle based on the propulsion force.

System and method for solar-powered airship

Abstract: A solar-powered airship with a hull configured to contain a gas and at least one propulsion assembly with a propulsion device and electric motors configured to drive the propulsion device. The airship may also include a power supply system including solar panels operatively coupled to the electric motors and configured to supply power to the electric motors. The power supply system may also include batteries operatively coupled to the solar panels and configured to receive and store electrical energy supplied by the solar panels, the batteries being further operatively coupled to the electric motors and configured to supply power to the electric motors. The batteries may each be located within an outer envelope of the airship defined by the hull of the airship in a position selected to provide ballast. The solar-powered airship may also include a cargo system configured to contain passengers or freight.

A resonant squid-inspired robot unlocks biological propulsive efficiency.

Abstract: Elasticity has been linked to the remarkable propulsive efficiency of pulse-jet animals such as the squid and jellyfish, but reports that quantify the underlying dynamics or demonstrate its application in robotic systems are rare. This work identifies the pulse-jet propulsion mode used by these animals as a coupled mass-spring-mass oscillator, enabling the design of a flexible self-propelled robot. We use this system to experimentally demonstrate that resonance greatly benefits pulse-jet swimming speed and efficiency, and the robot’s optimal cost of transport is found to match that of the most efficient biological swimmers in nature, such as the jellyfish Aurelia aurita. The robot also exhibits a preferred Strouhal number for efficient swimming, thereby bridging the gap between pulse-jet propulsion and established findings in efficient fish swimming. Extensions of the current robotic framework to larger amplitude oscillations could combine resonance effects with optimal vortex formation to further increase propulsive performance and potentially outperform biological swimmers altogether.