Preferred Language
Articles
/
Zxem7ZEBVTCNdQwCfJy0
Hierarchical Stabilization and Tracking Control of a Flexible-Joint Bipedal Robot Based on Anti-Windup and Adaptive Approximation Control
...Show More Authors

Bipedal robotic mechanisms are unstable due to the unilateral contact passive joint between the sole and the ground. Hierarchical control layers are crucial for creating walking patterns, stabilizing locomotion, and ensuring correct angular trajectories for bipedal joints due to the system’s various degrees of freedom. This work provides a hierarchical control scheme for a bipedal robot that focuses on balance (stabilization) and low-level tracking control while considering flexible joints. The stabilization control method uses the Newton–Euler formulation to establish a mathematical relationship between the zero-moment point (ZMP) and the center of mass (COM), resulting in highly nonlinear and coupled dynamic equations. Adaptive approximation-based feedback linearization control (so-called adaptive computed torque control) combined with an anti-windup compensator is designed to track the desired COM produced by the high-level command. Along the length of the support sole, the ZMP with physical restrictions serves as the control input signal. The viability of the suggested controller is established using Lyapunov’s theory. The low-level control tracks the intended joint movements for a bipedal mechanism with flexible joints. We use two control strategies: position-based adaptive approximation control and cascaded position-torque adaptive approximation control (cascaded PTAAC). The interesting point is that the cascaded PTAAC can be extended to deal with variable impedance robotic joints by using the required velocity concept, including the desired velocity and terms related to control errors such as position, force, torque, or impedance errors if needed. A 6-link bipedal robot is used in simulation and validation experiments to demonstrate the viability of the suggested control structure.

Scopus Clarivate Crossref
View Publication
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
An Ecological Study of the Brown Garden snail Cornu aspersum (Müller, 1774) from selected habitats in Jadiriya in Baghdad vicinity.
...Show More Authors

The present study is considered a pioneer investigation that deal with the terrestrial brown garden snail Cornu aspersum (Müller), in Iraq. Cornu aspersum however is considered an exotic species in many parts of the world ,The species is most probably infiltrates with plants transferred from one place to another. The species has gained importance in many ways. Nutritionally, the species is consumed as food item in many countries, but in other cases it is considered as pest for the damage it causes when feeding on valuable plant shoots. It also has medical importance for its role and ability in healing wounds, burns and remedy of other skin problems. This snail species however may act as a vector for some parasitic nematodes that

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Sep 07 2008
Journal Name
Baghdad Science Journal
The antiviral activity of the compound chalcone (4-ethoxy-2-hydroxy-4, 6-dimethoxy-chalcone) against rubella virus in vitro
...Show More Authors

The studies on the antiviral compound chalcone in vitro in both tissue and organ culture systems against rubella virus glass that this compound relatively non toxic to the cell culture and organ culture of the concentration of 8 ug/ml or less, chalcone have significantly antiviral activity against rubella virus in tissue culture and organ culture. We find that a concentration of 0.03ug/ml or more inhibit the IOOTCID50 of rubella virus. The therapeutic index (TI) used in this study to evaluate the drug, the (TI) which is the ratio of the dose of drug which is just toxic (Maximum tolerated dose) to the dose which is just effective (Minimum effective dose). If this index is one or less it not possible to use the drug under the conditions outli

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Mar 23 2022
Journal Name
Journal Of Educational And Psychological Researches
The effect of the reciprocal reading strategy in developing innovative reading skills for fifth-year secondary school students / scientific branch
...Show More Authors

       This research aims to identify the impact of the reciprocal reading strategy on developing the innovative reading skills of fifth-grade secondary school students/ scientific branch. To achieve the goal of the research, an achievement test to measure the academic achievement of fifth-grade secondary school students in  Arabic language grammar was prepared,  a sample of (60) female students from the secondary school of Al- Bawaba Al-Sharkey for Girls in Baghdad were chosen for the academic year (2019-2020). For the purpose of applying the experiment, the test was applied on a pilot sample consisting of (30) students from the same research community. The researcher herself had taught the three

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 01 2021
Journal Name
Al-khwarizmi Engineering Journal
The The Application of Virtual Reality to (Mechatronics Engineering) by Creating an Articulated Robotic Work Cell Using EON Reality V9.22.24.24477
...Show More Authors

Virtual reality, VR, offers many benefits to technical education, including the delivery of information through multiple active channels, the addressing of different learning styles, and experiential-based learning. This paper presents work performed by the authors to apply VR to engineering education, in three broad project areas: virtual robotic learning, virtual mechatronics laboratory, and a virtual manufacturing platform. The first area provides guided exploration of domains otherwise inaccessible, such as the robotic cell components, robotic kinematics and work envelope.  The second promotes mechatronics learning and guidance for new mechatronics engineers when dealing with robots in a safe and interactive manner. And the thir

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Use aggregate slide estimate additive splines estimation for the diagnosis of non-linear composite model self-regression with practical application
...Show More Authors

Nonlinear time series analysis is one of the most complex problems ; especially the nonlinear autoregressive with exogenous variable (NARX) .Then ; the problem of model identification and the correct orders determination considered the most important problem in the analysis of time series . In this paper , we proposed splines  estimation method for model identification , then we used three criterions for the correct orders determination. Where ; proposed method used to estimate the additive splines for model identification , And the rank determination depends on the additive property  to avoid the problem of curse dimensionally . The proposed method is one of the nonparametric methods , and the simulation results give a

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Feb 13 2023
Journal Name
Journal Of Educational And Psychological Researches
The Reality of Using Electronic Applications in Teaching Language Skills to People with Mild Intellectual Disability from the Mothers’ Perspective
...Show More Authors

Abstract

This study aims to identify the reality of using electronic applications in teaching language skills to people with mild intellectual disabilities from the mothers’ perspective. A descriptive approach was used. The electronic questionnaires were administered to the study sample, 122 responses were received from mothers of the students with mild intellectual disability in Hafer Al-Baten schools. The response average rate was 94%. The results showed that there are statistically significant differences that are related to the variant of monthly income as for the barriers to using electronic applications in such schools, whereas there were no differences regarding the variant of monthly income regarding t

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Role of using the Relative Strength Index in Making Speculation Decision in Stock: Applied Research in the Iraq Stock Exchange
...Show More Authors

 The relative strength index (RSI) is one of the best known technical analysis indicators; it provides the speculators by prior signals about the future stock’s prices, and because the speculations in shares of companies which listed in the Iraq Stock Exchange have a high degree of risk, like risk of shares prices felling, so the speculators became committed to use some methods to reduce these risks, and one of these methods is the technical analysis by using the relative strength index (RSI) which enable the speculators of choosing the right time for buy and sell the stocks and the right time to enter or leave the market by using the historical rice data. And from here the problem of the research formulated as “Is the using of

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Nov 07 2025
Journal Name
Modern Sport
Determining standard levels to test the strength endurance characteristic of speed for basketball players for juniors aged under (16) years
...Show More Authors

View Publication
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Modrating Role of Dynamic Knowledge capabilies in Addressing Organizational Failures to Achieve Business Competitiveness: Applied Research in Dairy Industries
...Show More Authors

Purpose/ to build clear perceptions about the level of the effects of organizational failures on the competitiveness of dairy factories and the role of dynamic knowledge capabilities in minimizing these impacts

Mythology/ Design approach Use deduction approach, the research was conducted in four dairy factories in Baghdad (Abu Ghraib, Agriculture, Halal and Ayon Al-Rafidain). It was applied to a sample of (155) individuals representing a sample of the research community from factory owners, managers, Engineers, technicians and experienced workers in the dairy industry. The questionnaire was used as a main tool for collecting data, information and statistical tools in the extraction, testing and analysis o

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Nov 30 2024
Journal Name
Iraqi Journal Of Science
Utilizing the Gravity Method to Detect the Potential Effect of the Salt Dome in the Nahr Omar Oilfield, Southern Iraq
...Show More Authors

Geophysics is one of the branches of Earth sciences and deals with studying the Earth's interior by studying the variation of physical properties within rock layers. Applied geophysics depends on procedures that involve the measurements of potential fields, such as the gravitational method. One of the significant oil fields in southern Iraq is represented by the Nahr Omar structure. A power spectrum analysis (SPA) technique was used to collect gravity data within the chosen oil field area in order to confirm the salt dome in the subsurface layers. The analysis of SPA resulted from six surfaces representing the gravity variation values of the depths (m)14300, 3780, 3290, 2170, 810, and 93.5. Gravity surfaces have been converted to de

... Show More
View Publication Preview PDF
Scopus Crossref