Computer Simulation Method Research Articles

The near-isotropic elastic properties of interpenetrating composites reinforced by regular fibre-networks

It is highly demanding and challenging to maximise the stiffness of the interpenetrating phase composites (IPCs) while still keeping their isotropy. In this paper, the elastic properties of IPCs reinforced by three different types of regular lattice fibre networks are investigated by computer simulation and analytical methods. The numerical results indicate that the larger the difference between the Poisson’s ratios and the smaller the difference between the Young’s moduli of the constituent materials, the larger the Young’s moduli of these IPCs are. It is also found that structural hierarchy can enhance the stiffness of these IPCs by 30%. In addition, the three types of IPCs have Zener anisotropy factors in the range of 1.0±0.04 in most cases, could have an almost isotropic Young’s modulus two times larger than the Voigt limit, and a Poisson’s ratio with a positive or negative or zero value. Moreover, they are easy to manufacture, their Young’s moduli are in general 1.0–3.0 times those of the conventional particle or short fibre reinforced composites and other types of IPCs including those reinforced by the triply periodic minimal surface (TPMS) shells, and the type of IPCs with the largest Young’s modulus has been identified.

Simulation and optimization of magnetoelastic thin shells

Magnetoelastic thin shells exhibit great potential in realizing versatile functionalities through a broad range of combination of material stiffness, remnant magnetization intensity, and external magnetic stimuli. In this paper, we propose a novel computational method for forward simulation and inverse design of magnetoelastic thin shells. Our system consists of two key components of forward simulation and backward optimization. On the simulation side, we have developed a new continuum mechanics model based on the Kirchhoff-Love thin-shell model to characterize the behaviors of a megnetolelastic thin shell under external magnetic stimuli. Based on this model, we proposed an implicit numerical simulator facilitated by the magnetic energy Hessian to treat the elastic and magnetic stresses within a unified framework, which is versatile to incorporation with other thin shell models. On the optimization side, we have devised a new differentiable simulation framework equipped with an efficient adjoint formula to accommodate various PDE-constraint, inverse design problems of magnetoelastic thin-shell structures, in both static and dynamic settings. It also encompasses applications of magnetoelastic soft robots, functional Origami, artworks, and meta-material designs. We demonstrate the efficacy of our framework by designing and simulating a broad array of magnetoelastic thin-shell objects that manifest complicated interactions between magnetic fields, materials, and control policies.

Бесступенчатое управление индексом модуляции трехфазного преобразователя электропривода в режиме «flat-top»

The article discusses one of the ways of stepless overmodulation in a semiconductor three-phase voltage inverter implemented according to the B6 scheme. In the review part of the article, the features of the PWM and overmodulation (“flat-top”) modes are briefly considered. The formation of the maximum possible values of the output voltage of the converter is possible due to the maximum values of the modulation index and the voltage inverter coefficient. It is shown that a variable-modulation index in the "flat-top" mode has a number of significant advantages over a fixed one, formed, for example, by "mixing" the PWM reference signal with additional harmonic signals. The geometric interpretation of the positions of the inverter output voltage vectors on the plane and their connection with the PWM reference signal made it possible to synthesize a high-precision (basic) non-linear characteristic in the inverter reference voltage path and to form a linear stepless control law for the inverter output voltage when the “flat-top” of the specified voltage coefficient is activated. The results of comparison of the basic variant of converter output voltage control with a simpler one obtained by approximating the basic equations using numerical methods of mathematics and computer simulation are presented. The absolute error of the modulation index in the case of approximation is no more than one percent in the entire "flat-top" range. The hodographs of the output voltage of the inverter in the X-Y axes are given for three different coefficients of the converter during the transition from PWM to "flat-top". The advantages of the method include the simplicity of its implementation in a new or existing space-vector PWM, the implementation of which is carried out exclusively by a software product. This aspect makes this method particularly attractive in low budget drives.

МОДЕЛИРОВАНИЕ ПЕРЕКЛЮЧЕНИЯ ПЕРЕДАЧ АВТОМОБИЛЬНОЙ ТРАНСМИССИИ С ГИДРОТРАНСФОРМАТОРОМ

The aim of the work is to evaluate the influence of gear shift parameters on the performance indicators of an automobile transmission with a torque converter (TC). The research objective is to develop a computer dynamic model of an automobile transmission with a three-row planetary gearbox and a TC to assess the transmission quality. The research applies the method of computer simulation using the software package “Universal Mechanism”. The novelty of the work is building a computer dynamic model of an automobile transmission with a three-row planetary gearbox and a torque converter to study the processes of gear shifting. The work results in developing a computer model to study the dynamic processes in a car transmission to assess the influence of gear shift parameters on the performance indicators of a car transmission with a TC. Recommendations are given on choosing gear shift control parameters. The work findings state that increasing the rise time of the friction clutch tup compression force raises the TC efficiency and the synchronization time of the clutch disks, reduces the values of the maximum angular acceleration and the change rate in the angular acceleration of the vehicle wheels (Jerk), increases the work of the friction forces of the clutches (W) when shift up is engaged and reduces W when shift down is engaged regardless of the TC blocking. When upshifting is actuated, one can recommend the minimum value of tup, which provides an acceptable value of Jerk.

Разработка имитационной модели двухмассовой технологической вибрационной установки с электромагнитным возбуждением

The research performed is actual because it is necessary to improve methods of calculations of rapid dynamic processes in electrical units. The object of research is the construction of a two-mass technological vibration unit with electromagnetic excitation. The subject of research is the method of calculation based on the created simulation model of the vibration unit dynamic cha-racteristics in transient and stationary modes with respect to a form and frequency of the source voltage. The mathematical model is based on non-linear differential equations of the electrical and mechanical balance. The main objective of research is the development of a simulation model of a two-mass technological vibration unit with electromagnetic excitation using modern methods of computer simulation. The example of the numerical implementation of the mathematical model by structural modeling methods in the Matlab Simulink is considered and the computer model of the electromagnetic vibration unit is created. The examples of the calculation of dynamical cha-racteristics of electromagnetic vibration unit for the analysis of electromechanical processes in transient and stationary modes are presented. Some of calculated values of integral indicators describing conversion processes of electric energy consumed from a power supply are given. The proposed simulation model of a technological vibration unit can be used to calculate rapid dyna-mic processes in different modes to provide a rational choice of vibration unit parameters when it is designed. The model is also useful for the analysis and synthesis of automatic systems to control the supplied voltage amplitude, frequency and form. The results of the research can be of particular interest to specialists in the area of machine strength dynamics and vibration protection.

Influence of the irradiation of ions of different mass on the formation of surface defects of lithium fluoride thin films

We explore the experimental and simulation results of the formation of defects on the surface of lithium fluoride thin films under irradiation with different mass ions using total current (TC) spectroscopy, secondary ion mass spectroscopy (SIMS), and the Stopping and Range of Ions in Matter (SRIM) software package. A comparative study was carried out with ions of different masses, and inconsistencies in the occurring physical phenomena between our early concepts were found. It is shown that in the case of heavy ions irradiation, they are implanted and appear as substitutional atoms into the bulk of the crystal. For ions with the smallest ion mass, the distribution of interstitial defects is greater on the surface than in the bulk of the crystal. An attempt is made to explain the formation of some defects on the surface (formed peaks in the TC spectra) by the method of computer simulation.

Advanced computational study of different boron nitride-based nanospheres for removal of organic contaminants from wastewater system

In the present work the removal of organic pollutants from wastewater was studied using a computational simulation method. Two nanospherical porous boron nitride (BN) materials namely, B16N16 and B12N12, were selected as adsorbent and the removal mechanism and adsorption ability of pure and glycine functionalized boron nitride adsorbents (B16N16(Glycine)2/B12N12(Glycine)2) were comprehensively evaluated in removal of two different emerging contaminants. The sigma profile (or charge density) study along with the quantum chemical calculations (using Materials Studio software) were obtained and discussed to predict the contaminant removal process.In particular, the adsorption ability and possible changes in the spectroscopic and electronic properties (Frontier molecular orbital, energy gap (ΔEGAP), chemical softness (σ), hardness (η)) of the pure and functionalized BN adsorbents before and after adsorption processes were studied. It was found that both functionalized adsorbents (B16N16(Glycine)2 and B12N12(Glycine)2) had higher adsorption ability. Moreover, according to the quantum chemical calculations B16N16(Glycine)2 adsorbent showed higher chemical reactivity and adsorption ability compare to other studied adsorbents due to the formation of cage interactions between pollutants and amino acid glycine of BN. According to the outcomes, Functionalization of the nanospherical boron nitride materials with glycine led to improvement in the pollutants adsorption affinity.

Scorpion Neurotoxin Syb-prII-1 Exerts Analgesic Effect through Nav1.8 Channel and MAPKs Pathway

Trigeminal neuralgia (TN) is a common type of peripheral neuralgia in clinical practice, which is usually difficult to cure. Common analgesic drugs are difficult for achieving the desired analgesic effect. Syb-prII-1 is a β-type scorpion neurotoxin isolated from the scorpion venom of Buthus martensi Karsch (BmK). It has an important influence on the voltage-gated sodium channel (VGSCs), especially closely related to Nav1.8 and Nav1.9. To explore whether Syb-prII-1 has a good analgesic effect on TN, we established the Sprague Dawley (SD) rats’ chronic constriction injury of the infraorbital nerve (IoN-CCI) model. Behavioral, electrophysiological, Western blot, and other methods were used to verify the model. It was found that Syb-prII-1 could significantly relieve the pain behavior of IoN-CCI rats. After Syb-prII-1 was given, the phosphorylation level of the mitogen-activated protein kinases (MAPKs) pathway showed a dose-dependent decrease after IoN-CCI injury. Moreover, Syb-prII-1(4.0 mg/kg) could significantly change the steady-state activation and inactivation curves of Nav1.8. The steady-state activation and inactivation curves of Nav1.9 were similar to those of Nav1.8, but there was no significant difference. It was speculated that it might play an auxiliary role. The binding mode, critical residues, and specific interaction type of Syb-prII-1 and VSD2rNav1.8 were clarified with computational simulation methods. Our results indicated that Syb-prII-1 could provide a potential treatment for TN by acting on the Nav1.8 target.

Оптимизация эксплуатационных расходов за счет улучшения условий взаимодействия подвижного состава и пути по параметру эквивалентной конусности

Purpose: Calculation of an economic effect by introducing the parameter of equivalent taper of wheel pairs on account of reduction of operating costs on high-speed train motion and track facility maintenance. Methods: The study used the methods of computer simulation of interaction between a rolling stock and a railway track, methods of mathematical statistics, methodology to make traction calculations in automated system. Results: Measures have been proposed to reduce the forces of a drag for a high-speed rolling stock motion. We’ve calculated an economic effect from introduction of wheel pair equivalent taper parameter on Russian Federation high-speed railroads. Practical importance: Recommendations have been proposed on consideration of wheel pair equivalent taper parameter for to reduce the forces of drag to the motion and on pursuing rail mobile treatment on the sections of high-speed train traffic sections.

Analysis dynamic characteristics brushless motor of the mechatronic system in conditions of parametric uncertaintyby computer simulation methods

THE PURPOSE. Currently, brushless motors – electric machines with permanent magnets on the rotor and a rotor position sensor controlled by a sinusoidal voltage from frequency converters, are widely used in mechatronic and robotic systems. The control algorithm is formed on the basis of information about the current values of the parameters brushless motor mechatronic system using a nominal or reference mathematical model, which is, as a rule, an idealized representation of a real device. The non-stationarity of the parameters object of study, as well as the possible uncertainty of its mathematical description due to the simplification of the mathematical model, lead to undesirable or unacceptable results when forming the control algorithm of the mechatronic system. The problem arises of analyzing the dynamic characteristics of a brushless motor under conditions of parametric uncertainty in order to determine the parameters that most affect the functioning of the mechatronic system and the phase coordinates that are sensitive to these changes.METHODS. When solving the problem, methods of the sensitivity theory are used to obtain the corresponding vector-matrix equations, the solution of which is carried out by means of the MatLab software environment.RESULTS. In this paper, sensitivity equations are obtained for the active resistance and projections of the stator winding inductance on the longitudinal and transverse coordinate axes, as well as for the moment of inertia of the brushless motor. A vector-matrix block diagram for calculating the sensitivity functions of a brushless motor is formed, the characteristic feature of which is the presence of a non-zero matrix of free terms, reduced to the input of the sensitivity model. The corresponding Simulink models were built to study the influence of the listed quasi-stationary parameters on the rotation speed and torque on the shaft of the object of study. An analysis of the statistical characteristics additional motion of the specified phase coordinates of the brushless motor has been carried out, and graphical dependencies and steady-state values of dispersions and relative estimates have been obtained.CONCLUSION. An analysis of the dynamic characteristics of a brushless motor under conditions of parametric uncertainty made it possible to determine that the rotation speed of the machine is the most sensitive to parametric disturbances. This coordinate is the most informative and is of maximum interest in the formation of an optimization algorithm for a mechatronic system. The decisive role in the formation of the additional movement of the output coordinates of the brushless motor is made by a change in the projection of the stator inductance on the transverse coordinate axis, which is an order of magnitude greater than the contribution to the additional movement of coordinates from other unstable parameters. It is expedient to use the results obtained in the course of the study when constructing an optimal control algorithm for a mechatronic system under conditions of parametric uncertainty.

On the Interaction between the Depth and Elevation of External Shading Devices in Tropical Daylit Classrooms with Symmetrical Bilateral Openings

External shading devices are an important design feature in tropical buildings, particularly for climate mitigation. However, the interaction between the depth and elevation of the shading devices and their impact on indoor daylight performance is not fully understood, especially for the case of tropical buildings with bilateral openings. This study therefore aims to evaluate the design possibilities of external shading devices with various depth and elevation in terms of daylight performance for the case of tropical school classrooms with bilateral openings in an Indonesian city. A computational simulation method using Radiance is utilized to perform annual daylight metrics calculations. Geometry, material, and simulation settings are prepared using the Ladybug tool under Grasshopper for four building orientations, namely 0°, 45°, 90°, and 135°. Sensitivity and uncertainty analyses are conducted for all design combinations. The results show that the interaction between a shading device’s depth and elevation is unique, depending on the building orientation and the availability of direct sunlight. In general, shading elevation is more influential, compared to shading depth, on the observed daylight metrics and the combined objective functions at all orientations.

Computational Simulation by Phase Field: Martensite Transformation Kinetics and Variant Selection under External Fields

Tailoring martensite transformation is critical for improving the mechanical properties of advanced steels. To provide preliminary guidance for the control of martensite transformation behaviour using external fields by computational simulation method, the phase-field method was used to calculate the morphology evolution, kinetics, and variant selection of the martensite transformation under different loading modes and magnetic field intensities. The incubation, transformation, and stable stages of the three variants based on the Bain strain group were investigated using different kinetic curves. These results clearly indicate that both uniaxial tension and compression can greatly promote the formation of martensite during the transformation stage and cause an obvious preferred variant selection. In contrast, the different variants have relatively balanced forms under shearing conditions. In addition, the magnetic field is a gentler way to form a state with balanced variants than other techniques such as shearing. Additionally, all these simulation results are consistent with classical martensitic transformation theory and thermodynamic mechanism, which proves the rationality of this research. The aim of the present study was to provide qualitative guidance for the selection of external fields for microstructural improvement in advanced steels.

A Novel Method for Preoperative Positioning of Total Ankle Replacement Using 3D Digital Model.

ObjectiveTo establish a digital model of the ankle joint through 3D imaging technology and explore the preoperative placement of ankle replacement prostheses.MethodsComputed tomography images of intact ankle joints from 54 cases in the outpatient and inpatient departments of our hospital were collected; according to the INBONE® total ankle system surgery process, the surgery model and surgical osteotomy were finished using MIMICS based on computer simulation method. The shortest distance was measured between the center point and the anterior, posterior, medial, and lateral, respectively, to ensure the precise position of the ankle replacement prosthesis by digital simulation surgery. The relationship between the two variables was analyzed by bivariate correlation analysis.ResultsThe dataset of this study included 48 cases of the sub‐data set (26 males and 22 females) and included 27 cases of left ankle and 21 cases of right ankle. The average medial malleolar angle was 18.67°± 2.87°, the average amount of bone resection was 12.13 ± 1.86 cm3, the mid‐anterior distance was 1.72 ± 0.19 cm, the mid‐posterior distance was 2.00 ± 0.19 cm, the ratio of mid‐anterior to mid‐posterior was 0.87, the mid‐medial distance was 1.26 ± 0.17 cm, the mid‐lateral distance was 1.19 ± 0.16 cm, and the ratio of mid‐medial to mid‐lateral was 1.06. After osteotomy, the anteroposterior diameter was 3.73 ± 0.32 cm, the transverse diameter was 2.46 ± 0.27 cm, and the ratio of anteroposterior diameter to transverse diameter was 1.53. In the bottom view, the shape after osteotomy is rectangular. The mid‐anterior distance was strongly negatively correlated with age, the mid‐anterior distance and the amount of bone resection, the mid‐medial distance and the amount of bone resection, the mid‐lateral distance and the amount of bone resection, the mid‐lateral distance and the anteroposterior diameter, the anteroposterior diameter and the transverse diameter were all strongly positively correlated.ConclusionThe projection point of the lower tibia centerline on the tibial horizontal osteotomy surface is located at a position slightly anterior to the midpoint of the transverse diameter after ankle arthroplasty. The rational positioning of the total ankle replacement is located at both a position slightly anterior to the midpoint of the transverse diameter and midpoint of the anteroposterior diameter, which can be used as a reference method before total ankle arthroplasty surgery.

Adaptive solar panel - overview and conceptual design

Renewable energy should reach its maximum usage capacity, around 20%, by 2025, as laid out by the Malaysian government to achieve the seventh Sustainable Development Goals (SDG): Affordable and clean energy. Many actions have been implemented to support the idea, including the development of solar energy panels in large photovoltaic installation. However, the installations require a wide area of land, and the efficiency offered is limited due to their fixed position. The efficiency of solar panels in absorbing the light from the sun is important to increase the energy supply. Several designs of the adaptive solar panel were developed by researchers, but the installation costs are high due to the components used. Commonly used actuators to move the solar panels are motor (DC motor, stepper motor, servo motor) that actuate according to the signals from photosensor, programming logic control (PLC), or microcontroller. Herein, the development of an Adaptive Solar Panel (ASP) is studied. SMA with high recoverability when it is strained is introduced as an actuator that capable of generating large actuation when heated to move the solar panel. In discovering the potential of SMA wire, a modern environmental-friendly design with six layers of solar panels with a rotational support system was designed in this study. In future work, the SMA wire actuation will be evaluated by computational simulation method using LS-Dyna.

Computer Simulation and Optimization of the Single-Crystal Nickel Superalloy Compositions: I. Modern Computer Simulation Methods in Designing Nickel Superalloys

Computer Simulation and Optimization of the Single-Crystal Nickel Superalloy Compositions: I. Modern Computer Simulation Methods in Designing Nickel Superalloys

Optimization of technological modes of heterogeneous systems at high turbulence

The phenomena of convective heat and mass transfer in turbulent flows, taking into account chemical reactions, are widespread and play an important role in natural phenomena and in various industries. Knowledge of the regularities of such flows is important in the formation of the theory of combustion physics, the development of new physical and chemical technologies, and the solution of problems of thermal power engineering and ecology. In the course of the study, complex combustion processes have been analyzed from the point of view of dependence on the influence of many physical and chemical parameters of the combustion reaction. In the study of phenomena in multiphase systems, the development of the theory of the formation of liquid droplets at high turbulence is of greatest interest. In this paper, the processes of atomization, ignition, and spatial distribution of droplets in heterogeneous two-phase flows have been studied by means of computer simulation methods. These studies were carried out on the basis of current environmental problems, including the problems of air pollution, consisting of harmful toxic metals, sulfuric, nitric acids, carbon oxides, and other harmful substances. The processes of dispersion and combustion of liquid fuels at high turbulence have been studied by using mathematical modeling methods based on the solution of partial differential equations and the optimal technological combustion mode taking into account the formation of carbon dioxide in the combustion chamber has been determined.

БЕСКОНТАКТНЫЙ ФЕРРОЗОНДОВЫЙ ДАТЧИК ПОЛОЖЕНИЯ ДЛЯ КОНТРОЛЯ СОСТОЯНИЯ КЛАПАНА

The aim of the study is to develop a non-contact fluxgate position sensor to control the open/ closed state of the valve. There are many examples of the use in modern technology of elementsor devices that interact with a magnetic field. One of the most urgent tasks is to use the influenceof the magnetic field as a means of control or as a component of the control environment. The useof magneto-optical sensors for monitoring the functioning of technical objects is due to their noncontactmeasurement method, the ability to measure not only magnetic, but also various otherphysical quantities, the relative simplicity, reliability and low cost of the design of the sensitiveelement, flexibility in use, operation in low-temperature and high-temperature environments.One of the sensors of this type is a fluxgate magnetic field converter. Valves of variouspneumohydraulic systems are an example of the object of introduction of a fluxgate sensor.The essence of the task is to create a non-contact limit switch of the valve spool, signaling theclosed or open state of the valve and transmitting this information to the control system. It is proposedto divide this task into stages and their sequential implementation. First, a search and analysisof existing solutions that implement the position sensor using the fluxgate control method iscarried out to improve the design being developed. Next, the initial design of the sensitive elementof the fluxgate transducer is developed, according to the initial design, a geometric 3D model ofthe sensitive element is created, and the proposed material of the constituent elements of the sensoris selected. With the help of numerical methods of computer simulation, the operation of thesensor is simulated and its output characteristic is determined under various operating modes.According to the design characteristics, the optimal design and configuration of the sensor's sensingelement is selected and calculated. As a result of the simulation, assembly and working drawingsof the sensor are developed. The proposed method for solving the problem is characterized bythe complexity of studying nonlinear magnetic systems and their modeling. The results of this studycan be recommended for the development of magneto-optical sensors of this or another type andfor the study of materials with nonlinear magnetic properties.

From a Computational Perspective: Elucidating the Neurotherapeutic and Inhibitory properties of LRRK2 Kinase Domain by a benzothiazole-based compound.

Parkinson's disease (PD) is one of the most prominent neurodegenerative diseases hence the continual search for viable and effective treatment options. The pathogeny of PD is driven by many key proteins among which is the recently identified Leucine-rich repeated kinase 2 (LRRK2). Going forward, the onus lies on identifying small-molecule inhibitors that can halt its pathogenic involvement, and, importantly, possess the capacity to cross the blood-brain barrier (BBB). Although several compounds have been identified over the past decade for their potencies, a major limitation remains the inability of the majority to cross the blood-brain barrier (BBB). A novel series of benzothiazole-based compounds with varying LRRK2 inhibitory activities were recently synthesized, with one compound 14 (CPD14) that notably inhibited LRRK2 and promoted neuronal progenitor proliferation. Here, we implemented molecular modelling and computational simulation methods to characterize CPD14 inhibitory mechanisms and dynamics against LRRK2. More so, we employed pharmacokinetic parameters to evaluate the biological activity and CNS-suitability of CPD14. Molecular dynamics evaluation revealed that CPD14 elicited disruptive effects on the secondary structure of LRRK2, including its catalytic kinase domain. Interaction analyses at the binding site further revealed crucial residues for the affinity binding and stability of CPD14, further supported by a highly favorable binding energy (ΔG). Pharmacokinetic predictions revealed the CNS-suitability of CPD14 based on its adherence to Lipinski's rule of 5 for neurogenic compounds. Also, CPD14 exhibited inhibitory tendencies against transcription proteins such as signal transducer and activation transcription (STAT) protein and STAT3; complementary mechanisms that could account for its in vitro potency. These findings, taken together, will aid the pharmacological and pharmacokinetic optimization of novel LRRK2 inhibitors for the treatment of PD.

Circuit designs for construction of pancratic telescopes

The improvement of classical telescopes designed to observe distant objects is currently associated with the provision of operating modes with interchangeable magnification and the possibility of photo and video recording. The purpose of the paper is to propose circuit designs for optical systems of high-magnification pancratic telescopes and substantiate the possibility of their use in engineering. The paper is based on the engineering design of two variants of telescope optical systems with a magnification of 20 to 60 times, in the first of which the pancratic change of magnification is provided by the movements of the components in the ocular part, in the second - in the objective part. The characteristics of pancratic telescopes are considered. It was revealed that in modern models the pancratic change of magnifications is carried out in the ocular and objective parts of the system. Computer simulation methods were used to synthesize optical schemes in the paraxial approximation, followed by the implementation of systems with finite apertures and thicknesses. The developed systems can be used at domestic enterprises of optical instrumentation.

Understanding the differences in wear testing method standards for total knee replacement

Preclinical evaluation of the wear of total knee replacements (TKR) is usually undertaken using International Standards Organization (ISO) test methods. Two international standards for the preclinical wear simulation of TKRs have been developed; using either force or displacement control. In addition, based on previously published measured kinematics of healthy subjects, a gait cycle (displacement control) was also developed at the University of Leeds, which pre-dates the ISO displacement control standard. Furthermore, different test methods have adopted different approaches to defining the centres of rotation and polarity (direction of application) of motions. However, the effects of using these different control regimes and input conditions on the kinematics, contact mechanics, and wear of any one TKR have not been fully investigated previously.The current study investigated the kinematics, contact mechanics, and wear performance of a TKR when running under ISO force and displacement control test methods as well as the Leeds gait cycle inputs using experimental and computational simulation methods, with the aim of understanding the mechanical and tribological outcomes predicted by the different test method standard conditions. Three ISO wear testing standards were investigated using a mid-size Sigma curved TKR (DePuy, UK), with moderately cross-linked UHMWPE curved inserts; ISO-14243-3-2004, ISO-14243-3-2014 and ISO-14243-1-2009. In addition, the Leeds displacement control gait cycle was also investigated.According to the computational simulation predictions, reversing the anterior-posterior (AP) displacement and tibial rotation polarities in the displacement control ISO-2014 standard compared to the ISO-2004 standard resulted in high stress, of more than 65 MPa, at the posterior edge of the inserts with more than 10% increase in wear rate for this TKR design. Although Leeds gait input kinematics produced femoral rollback, it did not result in high stress edge loading on the posterior lip of the insert. This was attributed to different test input kinematics and different centres of rotation of the femoral component adopted in the displacement control standard ISO-2014 and Leeds gait test methods. The predicted AP displacement and tibial rotation from the force control ISO-2009 had different polarities and magnitudes to the corresponding displacement control profiles. In addition, the predicted wear rate, from the computational model, under the force control ISO-2009 standard was more than double that predicted under displacement control ISO standards due to the increased AP displacement and tibial rotation motions predicted under the force control standard.These major differences, in the mechanics and wear, between different test methods imply that each standard must therefore be used with its own predicate control results from a device with proven clinical history and results across different standards should never be compared, as the choice of test method standard may well be dependent on the design solution for the knee. Clinically, the kinematics in the population are extremely variable, which results in highly variable wear rates. While a standard method is necessary, on its own it is not adequate and needs to be supported by tests under a portfolio of representative conditions with different kinematic conditions, different soft tissue constraints, as well as with different alignments, so that the variability and range of wear rates expected clinically might be determined. This study enables further progress towards the definition of such a portfolio of representative conditions, by deepening the understanding of the relationships between currently used input conditions and the resulting mechanical and wear outputs.