Experiments with Aerial Screw Propellers

Experiments with Cooperative Aerial-Ground Robots

Heterogeneous robot groups are a promising research direction for automating diverse tasks. A functional diierence between individual robot capabilities is likely to allow task-based specialization within the group. We report on experiments with a mechanically heterogeneous robot group consisting of a robotic helicopter and multiple wheeled ground robots. We present a behavior-based control sys...

Stochastic Flights of Propellers

Kilometer-sized moonlets in Saturn’s A ring create S-shaped wakes called “propellers” in surrounding material. The Cassini spacecraft has tracked the motions of propellers for several years and finds that they deviate from Keplerian orbits having constant semimajor axes. The inferred orbital migration is known to switch sign. We show using a statistical test that the time series of orbital long...

A Four-Quadrant Thrust Controller for Marine Propellers with Loss Estimation and Anti-Spin: Theory and Experiments

In this paper a nonlinear thrust controller for fixed pitch marine propellers with torque loss estimation and an antispin strategy is presented. The controller, designed to operate in the four-quadrant plane composed by the shaft speed and the vessel speed, is a combination of a thrust controller developed for calm/moderate sea states and an anti-spin strategy to reduce power peaks and wear-and...

Leakage Experiments On A Running Twin Screw Compressor

A Flight Control System for Aerial Robots: Algorithms and Experiments

This paper presents a hierarchical flight control system for unmanned aerial vehicles. The proposed system executes high-level mission objectives by progressively substantiating them into machine-level commands. The acquired information from various sensors is propagated back to the higher layers for reactive decision making. Each vehicle is connected via standardized wireless communication pro...