Article
Multidisciplinary Sciences
James A. Kempton, Caroline H. Brighton, Lydia A. France, Marco KleinHeerenbrink, Sofia Minano, James Shelton, Graham K. Taylor
Summary: This article examines the hunting behavior of falcons and hawks, and models their flight trajectories using proportional navigation and mixed guidance. The results show that mixed guidance can accurately model their pursuit behaviors, whether using visual information alone or visual-inertial fusion.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2023)
Article
Automation & Control Systems
Meng-chen Ma, Shen-min Song
Summary: This paper proposes three-dimensional cooperative guidance laws with prescribed performance. By choosing the relative distance between the missiles and the target as a coordination variable and proposing a fixed-time cooperative guidance law along the line-of-sight (LOS), performance degradation due to time estimation errors can be avoided. The guidance laws for the elevation and azimuth of the LOS are developed by combining the LOS angle tracking error with a performance constraint function. The problem of prescribed performance control is transformed into the boundedness problem of the transformed error function. A fixed-time convergence disturbance observer is designed to address the issue of aggregate uncertainty. Simulation results demonstrate the effectiveness of the proposed guidance laws.
INTERNATIONAL JOURNAL OF CONTROL
(2023)
Article
Mechanics
T. S. Amer, S. A. Abdelhfeez, Rewan F. Elbaz
Summary: This work investigates the planar motion of a dynamical model with two degrees-of-freedom. It explores the behavior of a connected tuned absorber with a simple pendulum, taking into account the pendulum's pivot movement and harmonic excitation moment. Using Lagrange's equations, the controlling system for the motion is derived. The approximate solutions of the system are obtained using the approach of multiple scales, and the resonance cases are classified and analyzed. The study also examines the stability regions and the impact of various parameters on the motion.
ARCHIVE OF APPLIED MECHANICS
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Oleksandra V. Ivashchenko, Koert F. D. Kuhlmann, Ruben van Veen, Bas Pouw, Niels F. M. Kok, Nikie J. Hoetjes, Jasper N. Smit, Elisabeth G. Klompenhouwer, Jasper Nijkamp, Theodoor J. M. Ruers
Summary: The study investigated the accuracy of intraoperative surgical guidance during open liver resection, utilizing a semi-rigid organ approximation and electromagnetic tracking. Results showed that the system provided accurate and intuitive real-time visualization of liver anatomy and tumor's location, with average accuracy of 4.0 +/- 3.0 mm and minimal surgical delay. Future integration may involve faster intraoperative imaging like ultrasound, and the adaptable approach may benefit various clinical applications.
Article
Engineering, Multidisciplinary
Rai Bijay, Matsa Amarendra, Datta Asim
Summary: The increasing use of autonomous robots in agriculture aims to replace human labor and improve production yields. This paper proposes an autonomous navigation system for an agricultural mobile robot using the pure pursuit algorithm (PPA) assisted by the vector field histogram (VFH). The PPA guides the robot towards waypoints, while the VFH algorithm helps it steer away from obstacles. The 2-dimensional LiDAR sensors are used to monitor the environment through the VFH algorithm. The analysis of distance covered and iterations required in the PPA algorithm shows that the mobile robot can travel at a speed range of 2.5-25 km/hr with obstacle evasion, suitable for agricultural applications.
JOURNAL OF APPLIED SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Electrical & Electronic
Gauri Sahoo, Rabindra Kumar Sahu, Pratap Chandra Pradhan, Sidhartha Panda
Summary: This study proposes a type-2 fuzzy fractional order proportional integral derivative controller for frequency regulation of microgrid systems, and tunes it using the enhanced Harris Hawks optimization method. By comparing with other optimization algorithms, the dominance of this controller in different scenarios is established, and its performance under parameter variations is evaluated through an uncertainty study.
Article
Biology
Stephen M. Rogers, Joanna Riley, Caroline Brighton, Gregory P. Sutton, Darron A. Cullen, Malcolm Burrows
JOURNAL OF EXPERIMENTAL BIOLOGY
(2016)
Article
Multidisciplinary Sciences
Caroline H. Brighton, Adrian L. R. Thomas, Graham K. Taylor
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2017)
Article
Multidisciplinary Sciences
Swidbert R. Ott, Heleen Verlinden, Stephen M. Rogers, Caroline H. Brighton, Pei Shan Quah, Rut K. Vleugels, Rik Verdonck, Jozef Vanden Broeck
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2012)
Article
Biology
Caroline H. Brighton, Katherine E. Chapman, Nicholas C. Fox, Graham K. Taylor
Summary: Birds' aerial hunting behaviors are influenced by flight morphology and ecology, and this study found that gyrfalcons and peregrine falcons exhibit similar attack trajectories guided by a proportional navigation law. However, gyrfalcons operate at lower values of the guidance gain N, resulting in slower turning and longer paths to intercept compared to peregrine falcons. The lower N values in gyrfalcons may not be solely explained by physical constraints, suggesting potential factors such as individual experience or species-level ecological adaptation.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Behavioral Sciences
Caroline H. Brighton, Lillias Zusi, Kathryn A. McGowan, Morgan Kinniry, Laura N. Kloepper, Graham K. Taylor
Summary: The behaviors of predators and prey can impact catch success and predation risk, with lone bats being more vulnerable to attacks. The success of hawk attacks is determined by their maneuvers, with high-speed stoops and rolling grabs being more successful. Lone bats are attacked disproportionately often, but hunting efficiency is not decreased by group vigilance or confusion.
BEHAVIORAL ECOLOGY
(2021)
Article
Multidisciplinary Sciences
Marco KleinHeerenbrink, Lydia A. France, Caroline H. Brighton, Graham K. Taylor
Summary: This study examines the swooping trajectories of perching Harris' hawks and finds that they aim to minimize the distance flown after stalling, rather than minimizing time or energy consumption. The findings also suggest a heuristic principle that could guide reinforcement learning of autonomous perching.
Article
Multidisciplinary Sciences
Caroline H. Brighton, Laura N. Kloepper, Christian D. Harding, Lucy Larkman, Kathryn McGowan, Lillias Zusi, Graham K. Taylor
Summary: This study shows that hawks attacking swarming bats avoid confusion by steering towards a fixed point in the swarm instead of targeting any one individual.
NATURE COMMUNICATIONS
(2022)