scholarly journals Determining the parameters of the trajectory of the bucket of mining quarries excavators

2021 ◽  
Vol 280 ◽  
pp. 05013
Author(s):  
Valerii Tytiuk ◽  
Kamal Khandakji ◽  
Galina Sivyakova ◽  
Nadezhda Karabut ◽  
Oleksii Chornyi ◽  
...  
Keyword(s):  
Position Control ◽  
Control Method ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Mining Industry ◽  
Point Of View ◽  
Three Dimensions ◽  
Electric Drives ◽  
Coordinate Control ◽  
Electric Excavator

The bucket positioning of the excavator in three-dimensions (3-D) is the precondition of the robotic excavator starting automatized works. The electric excavator is one of the most widely used machinery in the mining industry, mainly due to its versatility and portability. Among the tasks performed by the excavator, there is a significant number of repetitive movements associated with moving the bucket to the unloading point and back to the face. Using automated functions to perform such repetitive tasks will not only significantly increase overall productivity, but also reduce energy consumption. This research is carried out to create a method of coordinate control of electric drives of the boom, dipper stick, and bucket of an electric excavator to perform accurate and efficient work. On the basis of the kinematic analysis of the excavator’s attachment system, the trajectory of the end of the working body can be determined from the point of view of the coordinated movement of the electric drives of the main mechanisms of the excavator. Thus, the complex algorithm of the excavator bucket 3-D position control can be carried out by coordinated control of the movement of three separate electric drives. This coordinate control algorithm was tested on the example of the EKG-8I excavator, and the results of the verification showed that this developed control method can satisfactorily perform the function of automatic control of the bucket position in three-dimensional space. Optimization of control will be further carried out based on the analysis of the energy efficiency of various possible trajectories.

scholarly journals Unified Switching between Active Flying and Perching of a Bioinspired Robot Using Impedance Control

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Shanshan Du ◽  
Heping Chen ◽  
Yong Liu ◽  
Runting Hu
Keyword(s):  
Animal Behavior ◽  
Position Control ◽  
Control Method ◽  
Impedance Control ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Control Methods ◽  
Prior Work ◽  
Control Approach ◽  
Three Dimensional Space

Currently, a bottleneck problem for battery-powered microflying robots is time of endurance. Inspired by flying animal behavior in nature, an innovative mechanism with active flying and perching in the three-dimensional space was proposed to greatly increase mission life and more importantly execute tasks perching on an object in the stationary way. In prior work, we have developed some prototypes of flying and perching robots. However, when the robots switch between flying and perching, it is a challenging issue to deal with the contact between the robot and environment under the traditional position control without considering the stationary obstacle and external force. Therefore, we propose a unified impedance control approach for bioinspired flying and perching robots to smoothly contact with the environment. The dynamic model of the bioinspired robot is deduced, and the proposed impedance control method is employed to control the contact force and displacement with the environment. Simulations including the top perching and side perching and the preliminary experiments were conducted to validate the proposed method. Both simulation and experimental results validate the feasibility of the proposed control methods for controlling a bioinspired flying and perching robot.

Extension of the Spatial PDI Model to Three Dimensions

1997 ◽  
Vol 84 (1) ◽  
pp. 176-178
Author(s):  
Frank O'Brien
Keyword(s):  
Population Density ◽  
Dimensional Space ◽  
Finite Lattice ◽  
Three Dimensional ◽  
Upper Bounds ◽  
Three Dimensions ◽  
Lower And Upper Bounds ◽  
Density Index ◽  
Three Dimensional Space

The author's population density index ( PDI) model is extended to three-dimensional distributions. A derived formula is presented that allows for the calculation of the lower and upper bounds of density in three-dimensional space for any finite lattice.

The Brain Stem Saccadic Burst Generator Encodes Gaze in Three-Dimensional Space

2008 ◽  
Vol 99 (5) ◽  
pp. 2602-2616 ◽  
Author(s):  
Marion R. Van Horn ◽  
Pierre A. Sylvestre ◽  
Kathleen E. Cullen
Keyword(s):  
Eye Movements ◽  
Brain Stem ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Saccadic Eye Movements ◽  
Three Dimensions ◽  
Related Information ◽  
Computer Based ◽  
Different Depths ◽  
The Brain

When we look between objects located at different depths the horizontal movement of each eye is different from that of the other, yet temporally synchronized. Traditionally, a vergence-specific neuronal subsystem, independent from other oculomotor subsystems, has been thought to generate all eye movements in depth. However, recent studies have challenged this view by unmasking interactions between vergence and saccadic eye movements during disconjugate saccades. Here, we combined experimental and modeling approaches to address whether the premotor command to generate disconjugate saccades originates exclusively in “vergence centers.” We found that the brain stem burst generator, which is commonly assumed to drive only the conjugate component of eye movements, carries substantial vergence-related information during disconjugate saccades. Notably, facilitated vergence velocities during disconjugate saccades were synchronized with the burst onset of excitatory and inhibitory brain stem saccadic burst neurons (SBNs). Furthermore, the time-varying discharge properties of the majority of SBNs (>70%) preferentially encoded the dynamics of an individual eye during disconjugate saccades. When these experimental results were implemented into a computer-based simulation, to further evaluate the contribution of the saccadic burst generator in generating disconjugate saccades, we found that it carries all the vergence drive that is necessary to shape the activity of the abducens motoneurons to which it projects. Taken together, our results provide evidence that the premotor commands from the brain stem saccadic circuitry, to the target motoneurons, are sufficient to ensure the accurate control shifts of gaze in three dimensions.

A Conceptual Design of a Measuring System of Tennis Batting Motion Attitude Based on MEMS Sensors

2012 ◽  
Vol 198-199 ◽  
pp. 1053-1056
Author(s):  
Liang Han ◽  
Jing Song Jin ◽  
Wei Zhang
Keyword(s):  
Measurement System ◽  
Position Control ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Human Movement ◽  
Sports Injury ◽  
Measuring System ◽  
Attitude Measurement ◽  
Instructional Role ◽  
System Composition

Tennis is a very elegant sport, with a strong sense of competitiveness and appreciation, which has gained more and more attentions in our country, and it tends to be a fashion. This project is to achieve the measurement of tennis batting motion attitude in three dimensional space using a combination of the three-axis MEMS(Micro-electromechanical Systems) sensors, and make research on the principle of measurement system, composition and data acquisition. Body posture measurement system is to measure the attitude measurement in human movement, it can be applied to study the movement posture or to meet the requirements of position control, which provides theoretical foundation for scientific training and prevention of sports injury and also plays a significant and instructional role in improving the training levels of tennis playing and generalizing nationwide fitness campaign.

scholarly journals Platonic solids generate their four-dimensional analogues

2013 ◽  
Vol 69 (6) ◽  
pp. 592-602 ◽  
Author(s):  
Pierre-Philippe Dechant
Keyword(s):  
Coxeter Groups ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Root Systems ◽  
Point Of View ◽  
Platonic Solids ◽  
Four Dimensions ◽  
Potential Applications ◽  
Regular Convex ◽  
Quasi Crystals

This paper shows how regular convex 4-polytopes – the analogues of the Platonic solids in four dimensions – can be constructed from three-dimensional considerations concerning the Platonic solids alone.Viathe Cartan–Dieudonné theorem, the reflective symmetries of the Platonic solids generate rotations. In a Clifford algebra framework, the space of spinors generating such three-dimensional rotations has a natural four-dimensional Euclidean structure. The spinors arising from the Platonic solids can thus in turn be interpreted as vertices in four-dimensional space, giving a simple construction of the four-dimensional polytopes 16-cell, 24-cell, theF4root system and the 600-cell. In particular, these polytopes have `mysterious' symmetries, that are almost trivial when seen from the three-dimensional spinorial point of view. In fact, all these induced polytopes are also known to be root systems and thus generate rank-4 Coxeter groups, which can be shown to be a general property of the spinor construction. These considerations thus also apply to other root systems such as A_{1}\oplus I_{2}(n) which induces I_{2}(n)\oplus I_{2}(n), explaining the existence of the grand antiprism and the snub 24-cell, as well as their symmetries. These results are discussed in the wider mathematical context of Arnold's trinities and the McKay correspondence. These results are thus a novel link between the geometries of three and four dimensions, with interesting potential applications on both sides of the correspondence, to real three-dimensional systems with polyhedral symmetries such as (quasi)crystals and viruses, as well as four-dimensional geometries arising for instance in Grand Unified Theories and string and M-theory.

Distributed Constrained Attitude and Position Control Using Graph Laplacians

2010 ◽  
Author(s):  
Innocent Okoloko ◽  
Yoonsoo Kim
Keyword(s):  
Attitude Control ◽  
Position Control ◽  
Dimensional Space ◽  
Stochastic Matrix ◽  
Three Dimensional ◽  
Laplacian Matrix ◽  
Semidefinite Program ◽  
Graph Theoretic ◽  
Graph Laplacians ◽  
Quadratically Constrained

We present a graph theoretic and optimization based method for attitude and position consensus of a team of communicating vehicles navigating in three dimensional space. Coordinated control of such vehicles has applications in planetary scale mobile sensor networks, and multiple vehicle navigation in general. Using the Laplacian matrix of the communication graph, and attitude quaternions, a synthesis of the optimal stochastic matrix that drives the attitudes to consensus, is done, by solving a constrained semidefinite program. This novel methodology attempts to extend quadratically constrained attitude control (Q-CAC), to the consensus framework. The solutions obtained are used to realize coordinated rendezvous, and formation acquisition, in the presence of static and dynamic obstacles.

Estimating Three-Dimensional Space from Multiple Two-Dimensional Views

1993 ◽  
Vol 2 (1) ◽  
pp. 44-53 ◽  
Author(s):  
Kristinn R. Thorisson
Keyword(s):  
Visual Search ◽  
Eye Movement ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Simple Algorithm ◽  
Three Dimensions ◽  
Limiting Factor ◽  
Single Subject ◽  
Search Performance ◽  
Two Dimensional

The most common visual feedback technique in teleoperation is in the form of monoscopic video displays. As robotic autonomy increases and the human operator takes on the role of a supervisor, three-dimensional information is effectively presented by multiple, televised, two-dimensional (2-D) projections showing the same scene from different angles. To analyze how people go about using such segmented information for estimations about three-dimensional (3-D) space, 18 subjects were asked to determine the position of a stationary pointer in space; eye movements and reaction times (RTs) were recorded during a period when either two or three 2-D views were presented simultaneously, each showing the same scene from a different angle. The results revealed that subjects estimated 3-D space by using a simple algorithm of feature search. Eye movement analysis supported the conclusion that people can efficiently use multiple 2-D projections to make estimations about 3-D space without reconstructing the scene mentally in three dimensions. The major limiting factor on RT in such situations is the subjects' visual search performance, giving in this experiment a mean of 2270 msec (SD = 468; N = 18). This conclusion was supported by predictions of the Model Human Processor (Card, Moran, & Newell, 1983), which predicted a mean RT of 1820 msec given the general eye movement patterns observed. Single-subject analysis of the experimental data suggested further that in some cases people may base their judgments on a more elaborate 3-D mental model reconstructed from the available 2-D views. In such situations, RTs and visual search patterns closely resemble those found in the mental rotation paradigm (Just & Carpenter, 1976), giving RTs in the range of 5-10 sec.

scholarly journals On a set of quartic surfaces in space of four dimensions; and a certain involutory transformation

1926 ◽  
Vol 110 (756) ◽  
pp. 700-708
Keyword(s):  
Present Note ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Quartic Surface ◽  
Four Dimensions ◽  
Cubic Surfaces ◽  
Mutual Relations ◽  
Quartic Surfaces ◽  
Three Dimensional Space

There exists in space of four dimensions an interesting figure of 15 lines and 15 points, first considered by Stéphanos (‘Compt. Rendus,’ vol. 93, 1881), though suggested very clearly by Cremona’s discussion of cubic surfaces in three-dimensional space. In connection with the figure of 15 lines there arises a quartic surface, the intersection of two quadrics, which is of importance as giving rise by projection to the Cyclides, as Segre has shown in detail (‘Math. Ann.,’ vol. 24, 1884). The symmetry of the figure suggests, howrever, the consideration of 15 such quartic surfaces; and it is natural to inquire as to the mutual relations of these surfaces, in particular as to their intersections. In general, two surfaces in space of four dimensions meet in a finite number of points. It appears that in this case any two of these 15 surfaces have a curve in common; it is the purpose of the present note to determine the complete intersection of any two of these 15 surfaces. Similar results may be obtained for a system of cubic surfaces in three dimensions, corresponding to those here given for this system of quartic surfaces in four dimensions, since the surfaces have one point in common, which may be taken as the centre of a projection.

scholarly journals Coherent structures and chaotic advection in three dimensions

2010 ◽  
Vol 654 ◽  
pp. 1-4 ◽  
Author(s):  
STEPHEN WIGGINS
Keyword(s):  
Dynamical Systems ◽  
Fluid Mechanics ◽  
Coherent Structures ◽  
Three Dimensional ◽  
Point Of View ◽  
Three Dimensions ◽  
Chaotic Advection ◽  
Periodic Flow ◽  
Two Dimensional ◽  
Time Periodic

In the 1980s the incorporation of ideas from dynamical systems theory into theoretical fluid mechanics, reinforced by elegant experiments, fundamentally changed the way in which we view and analyse Lagrangian transport. The majority of work along these lines was restricted to two-dimensional flows and the generalization of the dynamical systems point of view to fully three-dimensional flows has seen less progress. This situation may now change with the work of Pouransari et al. (J. Fluid Mech., this issue, vol. 654, 2010, pp. 5–34) who study transport in a three-dimensional time-periodic flow and show that completely new types of dynamical systems structures and consequently, coherent structures, form a geometrical template governing transport.

Sign in / Sign up

Export Citation Format

Share Document