Improved Trajectory Planning using Arbitrary Power Polynomials

1994 ◽  
Vol 208 (1) ◽  
pp. 3-13 ◽  
Author(s):  
A Kirecci ◽  
M J Gilmartin
Keyword(s):  
Trajectory Planning ◽  
Interpolation Method ◽  
Attractive Alternative ◽  
Mathematical Functions ◽  
General Application ◽  
Arbitrary Power ◽  
Recent Developments ◽  
Planning Methods ◽  
Machine Systems ◽  
Conventional Systems

Increasing demands for higher operational speeds, the need for flexible machinery and recent developments in microchip technology have made programmable machine systems an attractive alternative to conventional systems. However, some difficulties still remain for proper control of programmable systems, especially at higher speeds. These can be categorized into two groups: trajectory planning and trajectory tracking. Conventional trajectory planning methods are ineffective for general application, especially when velocity and acceleration conditions are included. There are many mathematical functions but polynomials are shown to be the most versatile for trajectory planning; however, these can give curves with unexpected oscillations, commonly called meandering. Tracking of a motion in this situation could engender severe practical problems. In this study, a new interpolation method using polynomials with arbitrary powers is proposed to overcome this disadvantage.

scholarly journals Classification of Grass and Forb Species on Riverdike Using UAV LiDAR-Based Structural Indices

2021 ◽  
Vol 15 (3) ◽  
pp. 268-273
Author(s):  
Naoko Miura ◽  
Tomoyo F. Koyanagi ◽  
Susumu Yamada ◽  
Shigehiro Yokota ◽  
◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Imperata Cylindrica ◽  
Grass Species ◽  
Herbaceous Vegetation ◽  
Small Complex ◽  
Recent Developments ◽  
Aerial Vehicle ◽  
Conventional Systems ◽  
Structural Indices

Herbaceous vegetation on riverdikes plays an important role in preventing soil erosion, which, otherwise, may lead to the collapse of riverdikes and consequently, severe flooding. It is crucial for managers to keep suitable vegetation conditions, which include native grass species such as Imperata cylindrica, and to secure visibility of riverdikes for inspection. If managers can efficiently find where suitable grass and unsuitable forb species grow on vast riverdikes, it would help in vegetation management on riverdikes. Classification and quantification of herbaceous vegetation is a challenging task. It requires spatial resolution and accuracy high enough to recognize small, complex-shaped vegetation on riverdikes. Recent developments in unmanned aerial vehicle (UAV) technology combined with light detection and ranging (LiDAR) may offer the solution, since it can provide highly accurate, high-spatial resolution, and denser data than conventional systems. This paper aims to develop a model to classify grass and forb species using UAV LiDAR data alone. A combination of UAV LiDAR-based structural indices, V-bottom (presence of vegetation up to 50 cm from the ground) and V-middle (presence of vegetation 50–100 cm from the ground), was tested and validated in 94 plots owing to its ability to classify grass and forb species on riverdikes. The proposed method successfully classified the “upright” grass species and “falling” grass species / forb species with an accuracy of approximately 83%. Managers can efficiently prioritize the inspection areas on the riverdikes by using this method. The method is versatile and adjustable in other grassland environments.

scholarly journals A Survey of Some Recent Developments on Higher Transcendental Functions of Analytic Number Theory and Applied Mathematics

Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2294
Author(s):  
Hari Mohan Srivastava
Keyword(s):  
Number Theory ◽  
Special Functions ◽  
Applied Mathematics ◽  
Analytic Number Theory ◽  
Review Article ◽  
Mathematical Functions ◽  
Analytic Number ◽  
Recent Developments ◽  
Transcendental Functions ◽  
Mathematical Sciences

Often referred to as special functions or mathematical functions, the origin of many members of the remarkably vast family of higher transcendental functions can be traced back to such widespread areas as (for example) mathematical physics, analytic number theory and applied mathematical sciences. Here, in this survey-cum-expository review article, we aim at presenting a brief introductory overview and survey of some of the recent developments in the theory of several extensively studied higher transcendental functions and their potential applications. For further reading and researching by those who are interested in pursuing this subject, we have chosen to provide references to various useful monographs and textbooks on the theory and applications of higher transcendental functions. Some operators of fractional calculus, which are associated with higher transcendental functions, together with their applications, have also been considered. Many of the higher transcendental functions, especially those of the hypergeometric type, which we have investigated in this survey-cum-expository review article, are known to display a kind of symmetry in the sense that they remain invariant when the order of the numerator parameters or when the order of the denominator parameters is arbitrarily changed.

Ship Hull Form Optimization Using Artificial Bee Colony Algorithm

2014 ◽  
Author(s):  
Fuxin Huang ◽  
Lijue Wang ◽  
Chi Yang
Keyword(s):  
Drag Reduction ◽  
Artificial Bee Colony ◽  
Interpolation Method ◽  
Ship Hull ◽  
Mathematical Functions ◽  
Hull Form ◽  
Abc Algorithm ◽  
Bee Colony ◽  
Hull Forms ◽  
Fast Flow

In this paper, artificial bee colony (ABC) algorithms are introduced to optimize ship hull forms for reduced drag. Two versions of ABC algorithm are used: one is the basic ABC algorithm, and the other is an improved artificial bee colony (IABC) algorithm. A recently developed fast flow solver based on the Neumann-Michell theory is used to evaluate the drag of the ship in the optimization process. The ship hull surface is represented by discrete triangular panels and modified using radial basis function interpolation method. The developed optimization algorithms are first validated by benchmark mathematical functions with different dimensions. They are then applied to the optimization of DTMB Model 5415 for reduced drag. Two optimal hull forms are obtained by the ABC and the IABC algorithms. A large drag reduction is obtained by both of the algorithms. The optimal hull form obtained by the IABC algorithm has larger drag reduction than that of the hull form from the ABC algorithm. The results show that two ABC algorithms can be used for optimizing ship hull forms and the IABC algorithm has better performance than the ABC algorithm for the tested case in ship hull form optimization.

Factors in the Usage of Mobile Phones in Japanese University EFL Classrooms

2013 ◽  
pp. 118-144
Author(s):  
George R. MacLean ◽  
James A. Elwood
Keyword(s):  
Foreign Language ◽  
University Students ◽  
Mobile Phones ◽  
Attractive Alternative ◽  
Successful Implementation ◽  
Japanese University ◽  
Recent Developments ◽  
Mediating Factor ◽  
Computers In Education ◽  
Efl Classrooms

This chapter considers factors that can play roles in the use of mobile phones in university English as a Foreign Language (EFL) classrooms in Japan. While recent developments have made such devices an increasingly attractive alternative to computers in education, issues such as cost and privacy have been noted by other research to be of some concern. This study investigated the use and perceptions of mobile phones by 249 university students studying EFL in Japan. Results indicated that although students declared varying levels of proficiency with their mobile phones, most were able to complete the tasks queried. Among factors that might inhibit successful implementation of the use of mobile phones for education, cost and security concerns were minimal, but student reservations about using mobile phones for educational tasks appeared to be a mediating factor.

scholarly journals A Multi-Sensor Based Roadheader Positioning Model and Arbitrary Tunnel Cross Section Automatic Cutting

Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 4955
Author(s):  
Changqing Yan ◽  
Wenxiao Zhao ◽  
Xinming Lu
Keyword(s):  
Real Time ◽  
Cross Section ◽  
Trajectory Planning ◽  
Hydraulic Cylinder ◽  
High Accuracy ◽  
Position Measurement ◽  
Coordinate Measurement ◽  
Positioning Method ◽  
Planning Methods ◽  
Tunnel Cross Section

Autonomous posture detection and self-localization of roadheaders is the key to automatic tunneling and roadheader robotization. In this paper, a multi-sensor based positioning method, involving an inertial system for altitude angles measurement, total station for coordinate measurement, and sensors for measuring the real-time length of the hydraulic cylinder is presented for roadheader position measurement and posture detection. Based on this method, a positioning model for roadheader and cutter positioning is developed. Additionally, flexible trajectory planning methods are provided for automatic cutting. Based on the positioning model and the trajectory planning methods, an automatic cutting procedure is proposed and applied in practical tunneling. The experimental results verify the high accuracy and efficiency of both the positioning method and the model. Furthermore, it is indicated that arbitrary shapes can be generated automatically and precisely according to the planned trajectory, employing the automatic cutting procedure. Therefore, unmanned tunneling can be realized by employing the proposed automatic cutting process.

scholarly journals Research on Trajectory Planning and Tracking of Hexa-copter

2018 ◽  
Vol 173 ◽  
pp. 02008
Author(s):  
Qiyu Wang ◽  
Huijie Zhang ◽  
Jinrong Han
Keyword(s):  
Trajectory Planning ◽  
Flight Control ◽  
Attitude Control ◽  
Control Method ◽  
Sliding Mode ◽  
Interpolation Method ◽  
Spline Interpolation ◽  
Variable Structure ◽  
Flight Trajectory ◽  
Attitude Stability

In this paper, the flight control problem of hexa-copter is studied in detail from threedimensional trajectory planning to tracking. Then the cubic spline interpolation method is used to generate the trajectory by using these time marked waypoints. The flight trajectory curve produced by this method is smooth, twice differentiable, and it is easy to control implementation. The flight dynamics model of the UAV has the characteristics of multi-input multi-output, strong coupling, under-actuation, severe nonlinearity and external environmental disturbance. In order to improve the accuracy of flight trajectory and the stability of attitude control, a multi-loop sliding mode variable structure control method is proposed to achieve the hexa-copter flight trajectory tracking. The simulation results show that this method can track the predetermined flight trajectory and keep the attitude stability of the UAV normally.

scholarly journals Modeling fMRI signals can provide insights into neural processing in the cerebral cortex

2015 ◽  
Vol 114 (2) ◽  
pp. 768-780 ◽  
Author(s):  
Simo Vanni ◽  
Fariba Sharifian ◽  
Hanna Heikkinen ◽  
Ricardo Vigário
Keyword(s):  
Computational Models ◽  
Real Life ◽  
Mass Action ◽  
System Level ◽  
Specific System ◽  
Physiological Mechanisms ◽  
Mathematical Functions ◽  
Neural Mass ◽  
Recent Developments ◽  
The Relationship

Every stimulus or task activates multiple areas in the mammalian cortex. These distributed activations can be measured with functional magnetic resonance imaging (fMRI), which has the best spatial resolution among the noninvasive brain imaging methods. Unfortunately, the relationship between the fMRI activations and distributed cortical processing has remained unclear, both because the coupling between neural and fMRI activations has remained poorly understood and because fMRI voxels are too large to directly sense the local neural events. To get an idea of the local processing given the macroscopic data, we need models to simulate the neural activity and to provide output that can be compared with fMRI data. Such models can describe neural mechanisms as mathematical functions between input and output in a specific system, with little correspondence to physiological mechanisms. Alternatively, models can be biomimetic, including biological details with straightforward correspondence to experimental data. After careful balancing between complexity, computational efficiency, and realism, a biomimetic simulation should be able to provide insight into how biological structures or functions contribute to actual data processing as well as to promote theory-driven neuroscience experiments. This review analyzes the requirements for validating system-level computational models with fMRI. In particular, we study mesoscopic biomimetic models, which include a limited set of details from real-life networks and enable system-level simulations of neural mass action. In addition, we discuss how recent developments in neurophysiology and biophysics may significantly advance the modelling of fMRI signals.

scholarly journals Numerical Aspects and Performances of Trajectory Planning Methods of Flexible Axes

2006 ◽  
Vol 1 (4) ◽  
pp. 35 ◽  
Author(s):  
Jean-Yves Dieulot ◽  
Issam Thimoumi ◽  
Frédéric Colas ◽  
Richard Béarée
Keyword(s):  
Optimal Control ◽  
Path Planning ◽  
Natural Frequency ◽  
Trajectory Planning ◽  
Input Shaping ◽  
Robot Arm ◽  
Frequency Mismatch ◽  
Planning Methods ◽  
Real Robot ◽  
Theoretical Results

Adequate Path Planning design is an important stage for controlling flexible axes because it may allow to cancel vibrations induced by oscillating modes. Among bang-bang profiles which are linked to optimal control, jerk assignment (acceleration derivative) and input shapers have been investigated. Theoretical results show the performance and robustness with respect to natural frequency mismatch. Practical validations on a real robot arm show the relevance of the jerk algorithm which is more robust with the same productivity performances as input shaping techniques.

Research on Kinematics Analysis and Trajectory Planning of Novel EOD Manipulator

2021 ◽  
Vol 11 (20) ◽  
pp. 9438
Author(s):  
Jianwei Zhao ◽  
Tao Han ◽  
Xiaofei Ma ◽  
Wen Ma ◽  
Chengxiang Liu ◽  
...  
Keyword(s):  
Trajectory Planning ◽  
Inverse Kinematics ◽  
Degrees Of Freedom ◽  
Random Number ◽  
Polynomial Interpolation ◽  
Interpolation Method ◽  
Joint Space ◽  
Work Requirements ◽  
Multiple Degrees Of Freedom ◽  
Quintic Polynomial

To address the problems of mismatch, poor flexibility and low accuracy of ordinary manipulators in the complex special deflagration work process, this paper proposes a new five-degree-of-freedom (5-DOF) folding deflagration manipulator. Firstly, the overall structure of the explosion-expulsion manipulator is introduced. The redundant degrees of freedom are formed by the parallel joint axes of the shoulder joint, elbow joint and wrist pitching joint, which increase the flexibility of the mechanism. Aiming at a complex system with multiple degrees of freedom and strong coupling of the manipulator, the virtual joint is introduced, the corresponding forward kinematics model is established by D–H method, and the inverse kinematics solution of the manipulator is derived by analytical method. In the MATLAB platform, the workspace of the manipulator is analyzed by Monte Carlo pseudo-random number method. The quintic polynomial interpolation method is used to simulate the deflagration task in joint space. Finally, the actual prototype experiment is carried out using the data obtained by simulation. The trajectory planning using the quintic polynomial interpolation method can ensure the smooth movement of the manipulator and high accuracy of operation. Furthermore, the trajectory is basically consistent with the simulation trajectory, which can realize the work requirements of putting the object into the explosion-proof tank. The new 5-DOF folding deflagration manipulator designed in this paper has stable motion and strong robustness, which can be used for deflagration during the COVID-19 epidemic.

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