scholarly journals The Three-Dimensional Imaging of Rock Wall Surface with the Use of Computer-Based Image Processing and Analysis

2015 ◽  
Vol 37 (1) ◽  
pp. 53-58
Author(s):  
Krzysztof Oleszko ◽  
Mariusz Młynarczuk
Keyword(s):  
Image Processing ◽  
Dimensional Space ◽  
Low Cost ◽  
Three Dimensional ◽  
Rock Material ◽  
Rock Wall ◽  
Image Processing And Analysis ◽  
Digital Mapping ◽  
Computer Based ◽  
Bit Planes

Abstract The paper presents two methods of digital mapping of rock walls in three dimensional space. The methods have been developed with the use of low-cost devices, which enable image acquisition, and processing methods based on digital image processing and analysis. Both methods are based on so-called shadow profilometry. One of those methods involved mapping the shape of the rock wall on casted mapped surface with analyzed laser lines. The second method was based on the analysis of projected set of bit planes. The planes were projected by computer projector. Both measurement methods have been tested in Miękinia porphyry quarry. The study involved rock wall measurements, which were repeated several times. The part of rock material was removed from the measured wall after each measurement. In order to verify the accuracy of the proposed methods of measurement, volume results obtained and based on digital methods were compared to the volume of removed rock material during measurement. Calculated results were characterized by small deviations which prove to be correct, and are a solid basis for further work on practical application of presented methods.

scholarly journals Quantitative measurement of syndesmophyte volume and height in ankylosing spondylitis using CT

2013 ◽  
Vol 73 (3) ◽  
pp. 544-550 ◽  
Author(s):  
Sovira Tan ◽  
Jianhua Yao ◽  
John A Flynn ◽  
Lawrence Yao ◽  
Michael M Ward
Keyword(s):  
Ankylosing Spondylitis ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Reliability And Validity ◽  
Intervertebral Disk ◽  
Ct Scans ◽  
Developmental Study ◽  
Coefficients Of Variation ◽  
Spine Ct ◽  
Computer Based

ObjectiveSyndesmophyte growth in ankylosing spondylitis can be difficult to measure using radiographs because of poor visualisation and semiquantitative scoring methods. We developed and tested the reliability and validity of a new computer-based method that fully quantifies syndesmophyte volumes and heights on CT scans.MethodsIn this developmental study, we performed lumbar spine CT scans on 38 patients and used our algorithm to compute syndesmophyte volume and height in four intervertebral disk spaces. To assess reliability, we compared results between two scans performed on the same day in nine patients. To assess validity, we compared computed measures to visual ratings of syndesmophyte volume and height on both CT scans and radiographs by two physician readers.ResultsCoefficients of variation for syndesmophyte volume and height, based on repeat scans, were 2.05% and 2.40%, respectively. Based on Bland–Altman analysis, an increase in syndesmophyte volume of more than 4% or in height of more than 0.20 mm represented a change greater than measurement error. Computed volumes and heights were strongly associated with physician ratings of syndesmophyte volume and height on visual examination of both the CT scans (p<0.0001) and plain radiographs (p<0.002). Syndesmophyte volumes correlated with the Schober test (r=−0.48) and lateral thoracolumbar flexion (r=−0.60).ConclusionsThis new CT-based method that fully quantifies syndesmophytes in three-dimensional space had excellent reliability and face and construct validity. Given its high precision, this method shows promise for longitudinal clinical studies of syndesmophyte development and growth.

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.

Parallel Articulated-Cable Exercise Robot (PACER): Novel Home-Based Cable-Driven Parallel Platform Robot for Upper Limb Neuro-Rehabilitation

2015 ◽  
Author(s):  
Aliakbar Alamdari ◽  
Venkat Krovi
Keyword(s):  
Upper Limb ◽  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Low Cost ◽  
Three Dimensional ◽  
Parallel Architecture ◽  
Upper Limb Rehabilitation ◽  
Home Based ◽  
Tensile Forces ◽  
Parallel Platform

This paper examines the design, analysis and control of a novel hybrid articulated-cable parallel platform for upper limb rehabilitation in three dimensional space. The proposed lightweight, low-cost, modular reconfigurable parallel-architecture robotic device is comprised of five cables and a single linear actuator which connects a six degrees-of-freedom moving platform to a fixed base. This novel design provides an attractive architecture for implementation of a home-based rehabilitation device as an alternative to bulky and expensive serial robots. The manuscript first examines the kinematic analysis prior to developing the dynamic equations via the Newton-Euler formulation. Subsequently, different spatial motion trajectories are prescribed for rehabilitation of subjects with arm disabilities. A low-level trajectory tracking controller is developed to achieve the desired trajectory performance while ensuing that the unidirectional tensile forces in the cables are maintained. This is now evaluated via a simulation case-study and the development of a physical testbed is underway.

MPU6050 MODULE CONTROL UNIT ON THE IC BUS BASED ON A MICROCONTROLLER

2021 ◽  
pp. 65-69
Author(s):  
А.Б. Буслаев ◽  
Н.Н. Кошелева ◽  
С.С. Белокопытов
Keyword(s):  
Flight Control ◽  
Temperature Sensor ◽  
Dimensional Space ◽  
Low Cost ◽  
Assembly Language ◽  
Three Dimensional ◽  
Control Unit ◽  
Control Flight ◽  
Micromechanical Systems ◽  
Simultaneous Reading

Рассматривается модуль GY-521, на котором установлена микросхема MPU6050, объединяющая в одном корпусе акселерометр, гироскоп и температурный датчик. Такие датчики изготовлены на основе микромеханических систем (МЭМС), основным преимуществом которых является малый размер, низкое энергопотребление и небольшая стоимость. Одновременное использование акселерометра и гироскопа позволяет определить изменение движения тела в трехмерном пространстве. Рассмотрены основные характеристики используемого модуля. Управление микросхемы осуществляется с помощью архитектуры интерфейса IC «ведущий-ведомый». В работе ведомым является MPU6050, а ведущим (производит запрос на чтение или запись данных) является микроконтроллер, имеющий в своем составе аппаратную шину передачи данных IC. Показана возможная программная реализация алгоритма подключения нескольких ведомых устройств (шести микросхем MPU6050). Представлена принципиальная схема подключения к одному порту ввода-вывода микроконтроллера. Рассмотрен алгоритм работы микроконтроллера с подключенными микросхемами (шестью) MPU6050. Приведены пример программы (с использованием языка ассемблер) инициализации связи с MPU6050, а также программа считывания данных для снятия последних измерений акселерометра, гироскопа, температурного датчика. Применение нескольких модулей с одновременным считыванием с них информации позволяет осуществлять контроль систем управления полетом, имеющих совокупность нескольких управляющих поверхностей и устройств The paper considers the GY-521 module, which is equipped with the MPU6050 chip, which combines an accelerometer, a gyroscope and a temperature sensor in one housing. Such sensors are made on the basis of micromechanical systems (MEMS), the main advantages of which are small size, low power consumption and low cost. The simultaneous use of an accelerometer and a gyroscope allows you to determine the change in the movement of a body in three-dimensional space. We considered the main characteristics of the module used. The control of the chip is carried out using the architecture of the IC interface "master-slave". In operation, the MPU6050 is the host, and the master (makes a request to read or write data) is a microcontroller that has an IC hardware data bus. We show a possible software implementation of the algorithm for connecting multiple slave devices (six MPU6050 chips). We present a schematic diagram of the connection to a single I/O port of the microcontroller. We consider the algorithm of operation of the microcontroller with connected chips (six) MPU6050. We give an example of a program (using the assembly language) for initializing communication with the MPU6050, as well as a program for reading data for taking the latest measurements of the accelerometer, gyroscope, and temperature sensor. The use of several modules with simultaneous reading of information from them allows you to control flight control systems that have a set of several control surfaces and devices

scholarly journals Design and Implementation of a 3-Dimensional Attitudes Estimator Device using Low Cost Accelerometer & Gyroscope with Microcontroller IDE

2020 ◽  
Vol 12 (2) ◽  
pp. 151-161
Author(s):  
M. RAJA ◽  
Ugur GUVEN ◽  
Kartikay SINGH
Keyword(s):  
Dimensional Space ◽  
Low Cost ◽  
Three Dimensional ◽  
3 Dimensional ◽  
Aerospace Applications ◽  
Vector Quantity ◽  
Measurement Units ◽  
Fixed Axis ◽  
The Stability ◽  
Three Dimensional Space

Navigation and guidance systems for most automobile as well as aerospace applications require a coupled chip setup known as Inertial Measurement Units (IMU) which, depending on the degree of freedoms, contains a Gyroscope (for maintaining orientation and angular velocity), Accelerometers (to determine acceleration in the respective direction) and a Magnetometer (to determine the respective magnetic fields). In the three-dimensional space, any required rotation analysis is limited to the coordinate systems and all subtended angles in either direction must be defined by a fixed axis to effectively estimate the stability and to define all the attitude estimates needed to compile different rotations and orientations. The Quaternions are mathematical notations used for defining rotations and orientation in three-dimensional space. The simplest terms Quaternions are impossible to visualize in a three-dimensional space; the first three terms will be identical to the coordinate system, but through Quaternions another vector quantity is added into the equations, which may in fact underline how we can account for all rotational quantities. The fundamental analysis of these components different applications for various fields is proposed.

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