Results 41 to 50 of about 3,999 (214)
Approximate Dynamic Programming via Sum of Squares Programming [PDF]
, 2012 We describe an approximate dynamic programming method for stochastic control problems on infinite state and input spaces. The optimal value function is approximated by a linear combination of basis functions with coefficients as decision variables.
Kamgarpour, Maryam +5 more
core +1 more source
Multimodal Locomotion: Next Generation Aerial–Terrestrial Mobile Robotics
Advanced Intelligent Systems, Volume 7, Issue 7, July 2025.Aerial–terrestrial robots can achieve efficient energy consumption and robust environmental interaction by adding morphological features, adapting forms for locomotion transitions, and integrating multiple platforms. This next generation of mobile robots advances real‐world robotic deployment for operations with complex tasks and tackle environments ...
Jane Pauline Ramirez, Salua Hamaza
wiley +1 more source
Spring and Power in Hovering Ornithopters
Advanced Intelligent Systems, Volume 7, Issue 7, July 2025.Only small ornithopters can hover, longest at the hummingbird size. This article reviews the drive and power of these hovering machines, focusing on elastic energy and thrust boosters. Unlike two‐winged designs, X‐winged and multiple‐V‐winged ornithopters benefit from lower disk loading and slower, smaller wingbeats, and the clap‐and‐fling effect ...
Gih‐Keong Lau +4 more
wiley +1 more source
Wake structure and kinematics in the vortex ring state [PDF]
, 2009 High-resolution computational simulations of the vortical wake of a rotor operating both near to and within the vortex ring state have been conducted using Brown's vorticity transport model.
Azuma +10 more
core +1 more source
Ground zero soil sampling: Trinity, 1945
Geology Today, Volume 41, Issue 4, Page 137-146, July/August 2025.At Trinity—the world's first nuclear weapons testing site—large quantities of soil were drawn into the fireball to redeposit either downwind as radioactive fallout or in the near‐field as a unique, anthropogenic silicate glass trinitite. Manhattan Project physicists and chemists came to see soils at the Trinity site as a useful medium to assess the ...
Edward R. Landa
wiley +1 more source
Jixie chuandong, 2022 The rotor shaft vibration of the helicopter transmission system is an important factor affecting its operational reliability. In order to improve the safety margin of torsional vibration of the rotor shaft system of a coaxial counter-rotating double ...
De Ni +4 more
doaj
A Special Kind of Sliding Mode Control for Nonlinear System With State Constraints
IEEE Access, 2019 This paper presents a control strategy named auxiliary surfaces sliding mode control (AS-SMC) by using Positive Invariant Set (PIS) to control a class of continuous nonlinear systems with state constraints.
Zhi Chen +4 more
doaj +1 more source
A Review of Modeling and Control Techniques for Unmanned Aerial Vehicles
Engineering Reports, Volume 7, Issue 6, June 2025.By systematically classifying UAV modeling techniques and comparing control methods, this paper addresses a notable gap in the current literature. Furthermore, it highlights emerging trends and challenges in UAV control systems, providing valuable insights to guide future research toward enhancing the stability, efficiency, and adaptability of ...
Elisabeth Andarge Gedefaw +2 more
wiley +1 more source
Effect of rotor stiffness and lift offset on the aeroacoustics of a coaxial rotor in level flight [PDF]
, 2009 The acoustic characteristics of a twin contra-rotating coaxial rotor configuration with significant flapwise stiffness are investigated in steady forward flight.
Brown, Richard +2 more
core
Helicopter tail rotor thrust and main rotor wake coupling in crosswind flight [PDF]
, 2010 The tail rotor of a helicopter with a single main rotor configuration can experience a significant reduction in thrust when the aircraft operates in crosswind flight. Brown’s vorticity transport model has been used to simulate a main rotor and tail rotor
Balch D. T. +9 more
core +1 more source