Torque Parameters Research Articles

APPLICATION OF DRY CELL HHO GAS GENERATOR WITH PULSE WIDTH MODULATION ON SINJAI SPARK IGNITION ENGINE PERFORMANCE

Dry cell HHO gas generator performance optimization was done by varying the duty cycle of pulse width modulation, pwm. HHO gas generated subsequently applied to the Sinjai spark ignition engine port injection, 2-cylinder 650 cc with gas inlet mechanism using a venturi. Variations performed on HHO gas generator is the duty cycle of pwm, ie 20%, 40%, 60%, 80% and 100% (or the same as non pwm). The parameters of performance were calculated includes specific energy input, efficiency and temperature of the HHO generator. HHO gas is obtained then used as a fuel mixture in the Sinjai engine and inserted through a venturi mechanism which is mounted on the duct of combustion air inlet. Furthermore, the effect of the addition of HHO gas on the performance of the Sinjai engine measured includes parameters of torque, power, BMEP, specific fuel consumption and thermal efficiency. Sinjai engine performance optimization done on setting ignition timing for minimum advance for best torque, MBT mechanism. The results show that optimum performance of HHO gas generator is generated by pwm system with 40% duty cycle with parameters such as specific energy input of 33,121 MJ/kg, generator efficiency of 20,064% and generator temperature can be maintained below 60 0 C. Application of HHO gas generator in point above on standart ignition timing Sinjai engine produce in an increase of performance such as torque, power, BMEP and thermal efficiency respectively of 2.27%, 2.76% and 3.05% and a decrease of bsfc 7.76 %. Retarded ignition timing is adjusted to MBT is able to increase performance such as torque, power, thermal efficiency, respectively 6.55%, 7,65%, 15,50% and a decrease of bsfc 22,06 %.

Influence of a brisk walking program on isokinetic muscular capacities of knee in sedentary older women.

This study analyzed the evolution in peak torque (PT) and mean power (MP) isokinetic parameters in the quadriceps and hamstring muscles of elderly sedentary women who were randomly selected to participate in a brisk walking program for 6months. The 121 sedentary women of this study presented a mean score of 5.3 (±1.7) on the Physical Activity Questionnaire for the Elderly and covered 86% of the theoretical distance on the 6-min walk test. The isokinetic evaluation was performed on both sides at 60°/s and 180°/s. PT and MP were selected for analysis. Women in the trained group (n=61) participated in a program of 78 sessions over 6months with three sets of 60min of exercise per week. For this group, heart rate, time and distance were, respectively, 125.2bt/min (±10), 37.9min (±4.2) and 3756.3m (±445.4). The analysis of the group×time interaction demonstrated an increase in the PT of the dominant-side hamstrings (p<0.001). In the trained group, we observed a significant increase in PT at 60°/s for the hamstrings on both sides (0.01<p<0.02) and a significant increase in MP for the hamstrings at 60°/s on the nondominant side (p<0.05). The study indicates a minor, though significant, influence of a brisk walking program on the peak torque and mean power of the quadriceps and hamstring muscles in sedentary women over 60years.

Design Analysis of a Magnetic Gear Box with Continuous Ratio Shifting

Magnetic gears offer important potential benefits compared with mechanical gears such as reduced maintenance, improved reliability, inherent overload protection, and physical isolation between the input and output shafts. This paper presents the theory and simulation results for a continuous magnetic gear box employed in wind generators, electric vehicles and other related applications in which continuous ratio of gear box is essential. The analysis is performed by Finite Element Method (FEM) to predict output torque, speed and magnetic field distribution inside the gear box. The gear box made up of an inner rotating part which is similar to the rotor of a 3 phase wound rotor induction motor and an outer rotating part which consists of 6 PM poles. Both the inner rotor and outer rotor can be exploited as a low/high speed rotating part. The output torque and other parameters are evaluated in steady state condition using vector analysis. Simulation results are in good agreement with theoretical analysis as well.

Computer Aided Kinematic Analysis of Toggle Clamping Mechanism

Toggle mechanism is used widely in the mechanical industry for various applications ranging from injection molding machines to tools & fixtures. Toggle clamps are available for different types to suit desired application. This paper explores the kinematic analysis of the toggle clamping mechanism. Toggle mechanism considered here is actuated by hydraulic cylinder. Position, velocity and acceleration analysis is described in this work, for this analysis toggle clamping mechanism is fragmented into two basic mechanisms, Slider-Crank mechanism and Four-Bar Mechanism. Slider-Crank generates torque and output force in the toggle clamp mechanism so emphasis is given on slider-crank mechanism in this work. Toggle clamp mechanism for work- piece bending operation is described in this work. Mechanical advantage of the linkage is the key parameter for linkage performance, mechanical advantage and it's relation with torque and link parameter is discussed in brief.

Direct Torque Control of Induction Motor with Cascaded Multilevel inverter

3 Abstract: In this Paper, an Intelligent Direct Torque Control (DTC) method is proposed for controlling induction motor using Multilevel inverter with space Vector Modulation (SVM).A stage of Artificial Neural Network (ANN) is utilised for predicting the target parameters with the corresponding input parameters change in motor torque and flux. The change in motor torque and flux parameters are extracted from the behaviour of the system with PI controller. The back propagation learning method is used to learn the ANN. By using the ANN output and PI controller outputs, PWM control signal are generated from the SVM technique and control the multilevel inverter. Then the proposed intelligent control technique is implemented in the MATLAB/Simulink and the effectiveness are analysed with five level cascaded inverter and comparing the results with PI cont roller and the proposed case. The comparison results shows that the proposed method have good speed control response. Keyword: DTC, SVM, ANN, Multilevel inverter, Induction motor.

Theoretical study of Solospun yarn torque

Purpose – Solospun technology is one of the most important new spinning methods, which is implemented by dividing Ring spinning triangle into several small primary triangles and one final triangle by a Solospun roller. That is, there are two parts of spinning triangle in the Solospun technology, including primary triangles part and final triangle part. In the general case, the primary triangles are much smaller than final triangle. Therefore, the purpose of this paper is to present theoretical study of Solospun yarn torqueby linking the fiber tension in the spinning triangle to yarn torque under the assumption that the primary triangles and the primary twist are ignored. Design/methodology/approach – The theoretical model of the residual torque within Solospun yarn due to the fiber tension was given. Then, as an application of the proposed method, 14.6 tex cotton yarns were taken as an example for the numerical simulations. The fiber tension in the Solospun spinning triangles and corresponding yarn torque were simulated numerically by using Matlab software. The relationships between yarn torque and spinning triangle parameters are analyzed according to the simulation results. Furthermore, the properties of spun yarns produced by the Solospun and Ring spinning system are evaluated and analyzed by using the simulation results. Findings – It is shown that comparing with the Ring spun yarn, Solospun yarn torque is a little larger. Meanwhile, with an increase of substrand number, the fluctuation of curve of average fiber tension in Solospun system is increased firstly, and then decreased, i.e. showing parabola shape, potentially leading to corresponding change of yarn torque. Originality/value – In this paper, theoretical study of Solospun yarn torque is presented by linking the fiber tension in the spinning triangle to yarn torque under the assumption that the primary triangles and the primary twist are ignored. The theoretical model of the residual torque within Solospun yarn due to the fiber tension was given.

Critical current destabilizing perpendicular magnetization by the spin Hall effect

The critical current needed to destabilize the magnetization of a perpendicular ferromagnet via the spin Hall effect is studied. Both the dampinglike and fieldlike torques associated with the spin current generated by the spin Hall effect is included in the Landau-Lifshitz-Gilbert equation to model the system. In the absence of the fieldlike torque, the critical current is independent of the damping constant and is much larger than that of conventional spin torque switching of collinear magnetic systems, as in magnetic tunnel junctions. With the fieldlike torque included, we find that the critical current scales with the damping constant as $\alpha^{0}$ (i.e., damping independent),$\alpha$, and $\alpha^{1/2}$ depending on the sign of the fieldlike torque and other parameters such as the external field. Numerical and analytical results show that the critical current can be significantly reduced when the fieldlike torque possesses the appropriate sign, i.e. when the effective field associated with the fieldlike torque is pointing opposite to the spin direction of the incoming electrons. These results provide a pathway to reducing the current needed to switch magnetization using the spin Hall effect.

Robust Sliding Mode Speed Controller-based Model Reference Adaptive System (MRAS) and Load Torque Estimator for Interior Permanent Magnet Synchronous Motor (IPMSM) Drives

This paper presents a robust sliding mode control (SMC)-based model reference adaptive system (MRAS) aimed at improving the dynamic performance of interior permanent magnet synchronous motor (IPMSM) drives. MRAS following a speed controller for IPMSM drives is developed. The error signal between the plant speed and MRAS speed is augmented to permit the prescribed specifications be maintained using SMC. The load disturbance is detected using a load torque estimator and is compensated through the q-axis current reference value. The load torque estimator is used to provide a feedforward value in the speed controller in order to decouple the load torque from the speed control. This method can improve IPMSM dynamic performance against the disturbance torque without increasing SMC gain due to both chattering and stability limitations. The complete field-oriented control of an IPMSM drive with the proposed controller is successfully implemented in real time using the DSP-DS1102 control board for a laboratory 1-hp motor. A performance comparison of the proposed controller with the conventional PI controller is also provided. The efficacy of the proposed controller is verified by simulation and experimentation under different operating conditions. It is found that the proposed controller provides an excellent speed response under load torque disturbance and parameter uncertainty.

Design of a fractional order adaptive controller for velocity control of a permanent magnet synchronous motor

Purpose – The purpose of this paper is to present a two-loop approach for velocity control of a permanent magnet synchronous motor (PMSM) under mechanical uncertainties. Design/methodology/approach – The inner loop calculates the two-axis stator reference voltages through a feedback linearization method. The outer loop employs an RST control structure to compute the q-axis stator reference current. To increase the robustness of the proposed method, the RST controller parameters are adapted through a fractional order model reference adaptive system (FO-MRAS). The fractional order gradient and Lyapunov methods are utilized as adaptation mechanisms. Findings – The effect of the fractional order derivative in the load disturbance rejection, transient response speed and the robustness is verified through computer simulations. The simulation results show the effectiveness of the proposed method against the external torque and mechanical parameters uncertainties. Originality/value – The proposed FO-MRAS based on Lyapunov adaptation mechanism is proposed for the first time. Moreover, application of the FO-MRAS for velocity control of PMSM is presented for the first time.

Decoding tactile afferent activity to obtain an estimate of instantaneous force and torque applied to the fingerpad.

Dexterous manipulation is not possible without sensory information about object properties and manipulative forces. Fundamental neuroscience has been unable to demonstrate how information about multiple stimulus parameters may be continuously extracted, concurrently, from a population of tactile afferents. This is the first study to demonstrate this, using spike trains recorded from tactile afferents innervating the monkey fingerpad. A multiple-regression model, requiring no a priori knowledge of stimulus-onset times or stimulus combination, was developed to obtain continuous estimates of instantaneous force and torque. The stimuli consisted of a normal-force ramp (to a plateau of 1.8, 2.2, or 2.5 N), on top of which -3.5, -2.0, 0, +2.0, or +3.5 mNm torque was applied about the normal to the skin surface. The model inputs were sliding windows of binned spike counts recorded from each afferent. Models were trained and tested by 15-fold cross-validation to estimate instantaneous normal force and torque over the entire stimulation period. With the use of the spike trains from 58 slow-adapting type I and 25 fast-adapting type I afferents, the instantaneous normal force and torque could be estimated with small error. This study demonstrated that instantaneous force and torque parameters could be reliably extracted from a small number of tactile afferent responses in a real-time fashion with stimulus combinations that the model had not been exposed to during training. Analysis of the model weights may reveal how interactions between stimulus parameters could be disentangled for complex population responses and could be used to test neurophysiologically relevant hypotheses about encoding mechanisms.

Model of spin accumulation and spin torque in spatially varying magnetisation structures: limitations of the micromagnetic approach

We study the spin-transfer torque acting on the magnetisation when injecting polarised conduction electrons into a magnetic system. The spin accumulation is calculated self-consistently and naturally includes the adiabatic and non-adiabatic contributions which depend on the rate of change of magnetisation in relation to the spin diffusion length. As an example we consider a system where a spin-polarised current is injected into a structure containing a domain wall. We calculate the spin torque and related parameters corresponding to the adiabatic and non-adiabatic terms directly from the spin accumulation, and find that the dynamic micromagnetic approach based on adiabatic and non-adiabatic terms with constant coefficients is valid only for systems with slowly spatially varying magnetisation.

Friction coefficient estimation in servo systems using neural dynamic programming inspired particle swarm search

Parameter estimation of static friction torques in servo control systems is of great significance to their robust control. Many researchers are devoted to pursuing the solutions to estimating the coefficients of the static friction torques. In order to tackle the troublesome matter more effectively, in this paper, we address a neural dynamic programming inspired particle swarm search algorithm. We call the algorithm direct BP neural dynamic programming inspired PSO (NDPSO) since we incorporate direct back propagation (BP) and neural dynamic programming (NDP) into particle swarm optimization (PSO). In NDPSO, critic BP neural network is trained to balance the Bellman equation while action BP neural network is used to train the inertia weight, the cognitive coefficient, and the social coefficient of the PSO algorithm. The training target is to enable the critic BP neural network output to approach the ultimately successful objective. Successively, NDPSO, together with standard PSO (SPSO) and genetic algorithm (GA), is applied to the parameter identification of the static friction torque in a servo control system with single input and single output (SISO). The experimental results clearly demonstrate that NDPSO is effective and outperforms SPSO and GA in identifying the parameters of the static friction torque in the servo control system.

Whirl Interaction of a Drill Bit with the Bore-Hole Bottom

This paper deals with the theoretic simulation of a drill bit whirling under conditions of its contact interaction with the bore-hole bottom rock plane. The bit is considered to be an absolutely rigid ellipsoidal body with uneven surface. It is attached to the lower end of a rotating elastic drill string. In the perturbed state, the bit can roll without sliding on the bore-hole bottom, performing whirling vibrations (the model of dynamic equilibrium with pure rolling when maximum cohesive force does not exceed the ultimate Coulombic friction). To describe these motions, a nonholonomic dynamic model is proposed, constitutive partial differential equations are deduced. With their use, the whirling vibrations of oblong and oblate ellipsoidal bits are analyzed, the functions of cohesive (frictional) forces are calculated. It is shown that the system of elastic drill string and ellipsoidal bit can acquire stable or unstable whirl modes with approaching critical Eulerian values by the parameters of axial force, torque and angular velocity. The analogy of the found modes of motions with ones of the Celtic stones is established. It is shown that the ellipsoidal bits can stop their whirling vibrations and change directions of their circumferential motions in the same manner as the ellipsoidal Celtic stones do. As this takes place, the trajectories of the oblate ellipsoidal bits are characterized by more complicated paths and irregularities.

Structure Design and Torque Characteristics Analysis of a Novel Transverse Flux Permanent Magnet Motor

A new type of transverse flux permanent magnet motor with surface-type permanent magnet rotor structure and silicon steel stator structure was designed. According to the new structure of transverse flux permanent magnet motor, the operating principle of the motor was given. The relationship among motor output torque, torque density, magnetic poles and winding parameters are deduced, and a reasonable method of designing motor size parameters was proposed. A three-dimensional finite element model of the motor was created and the model grid division was done using ANSYS finite element analysis software. According to different winding current values and different positions of stator and rotor, the motor magnetic flux density distribution, the output torque and inductance parameter were given through calculating the three dimensional finite element models. Finite element analysis results show that the new motor structure is reasonable.

Non-integrability for Motion of Natural and Artificial Satellite in an Elliptic Orbit under the Influence of Aerodynamic Torque

This article deals with the non-linear oscillation of a satellite in an elliptic orbit around the Earth under the influence of aerodynamic and gravitational torque. It is assumed that the orbital plane coincides with the equatorial plane of the Earth. Using Euler's dynamical equation of motion, the equation of motion, Hamiltonian function and Melnikov's integral for the problem is derived. Taking aerodynamic torque of the order of eccentricity, it is observed that Hamiltonian function is dependent on aerodynamic torque. Using Melnikov's method it is observed that equations of motion are non-integrable. The non-integrability is observed graphically and numerically in Earth-Moon system and Earth-Resources at-1 system. It is concluded that for Earth-satellite system (Earth-Moon and Earth-Resourcesat-1) the Melnikov's function has simple zeros with the change in mass parameter and aerodynamic torque parameter, thus the non-linear system for equation of motion is non-integrable.

Effect of Storage Temperature on Biochemical and Mixolab Pasting Properties of Chinese Japonica Paddy

&lt;p&gt;This study investigated the changes in germination rate, contents of oleic acids, protein, water soluble sugars, enthalpy of flour gelatinization, and Mixolab dough pasting properties of three varieties of &lt;em&gt;japonica&lt;/em&gt; rough rice after 18-month storage at four temperatures of 4,15,25 and 35 ºC. After an 18-month storage, the paddy stored at or below 25 ºC had more than 70% germination rate, their flour extracts by acid dye mixture of methyl red and bromothymol blue showed greenish color, but the paddy stored at 35 ºC was only 30% germination rates, their flour extracts by acid dye mixture seem to be yellowish. With an increase in storage temperature, mositure content in paddy decreased, but total protein changed unsignificantly. In comparison to the paddy stored at 15 ºC, the higher storage temperature (25 and 35 ºC) tends to decrease the contents of damaged starch, water-soluble reducing sugars, total sugars, and uronic acids. The content of oleic acid in paddy stored at 4 ºC was markedly higher than that at the temperatures of 15, 25 and 35 ºC. Compared to lower temperate (4 and 15 ºC), the higher storage temperature (35 ºC) increased the gelatinization enthalpy of paddy flour and its starch determined by a differential scanning calorimetry (DSC), also increased Mixolab characteristic torque parameters such as starch gelatinization peak (C3), starch gelatinization minimum (C4), starch retrogradation minimum (C5), degrees of starch decay (C3-C4) and retrogradation (C5-C4) with a decrease in protein weakening (C2). The results of this study indicate storage temperature is an important factor affecting the physiological and biochemical properties of paddy, and lower temperature below room temperature are recommended to maintain paddy quality.&lt;/p&gt;

Output Torque for Electromagnetic Harmonic Drive

The operation principle of an electromagnetic harmonic drive is analyzed and its speed ratio equation is given. The equations of the displacements of the flexible ring under magnetic forces and the equations of the output torque between the flexible ring and rigid one are deduced. Using these equations, the displacement distribution of the flexible ring is investigated, and the effects of the system parameters on output torque are discussed. The results show that the current intensity of the coils, the airgap, the iron core length, and the position of the rigid ring have effects on the output torque for the drive system. The current intensity can be taken as the main control parameter of the output torque.

Effects of isokinetic eccentric training on knee extensor and flexor torque and on gait of individuals with long term ACL reconstruction: A controlled clinical trial

This study investigated the effects of the isokinetic eccentric training (IET) on the knee extensor and flexor torque and kinematic gait parameters in individuals with ACL reconstruction. Sixteen men with ACL reconstructed (ACLr) whose torque and the gait were evaluated, before and after 12 weeks of IET, was compared to a control group (14 individuals). Student t, MANOVA and ANOVA tests were performed with 5% of significance. The training increased the isometric, concentric at 30 and 120º/s (p &lt; .05) and eccentric at 30º/s (p &lt; .01) extensor torque on the affected limb (AL), and eccentric at 30 and 120º/s (p &lt; .01), on the non-affected limb (NAL). In the flexors, there was an increase on the torque: isometric, concentric at 30º/s and eccentric at 30 and 120º/s (p &lt; .01) in AL and in eccentric at 30 (p &lt; .05) and 120º/s (p&lt; .01) in NAL. With respect to the angular and spatio-temporal variables gait, there was no difference between pre-and post-training in LCAr group. Compared to control group, the cycle time, in two members, was lower in LCAr group, and stride length and cadence were higher in the AL of the LCAr (p &lt; .05). Moreover, the knee flexion-extension angles (minimum and maximum) remained lower in LCAr, pre- and post-training (p &lt; .01). The torque gain associated with eccentric isokinetic training did not affect the kinematic parameters of gait in patients undergoing ACL reconstruction.

Tractable Algorithm for Robust Time-Optimal Trajectory Planning of Robotic Manipulators under Confined Torque

In this paper, the problem of time optimal trajectory planning under confined torque and uncertain dynamics and torque parameters along a predefined geometric path is considered. It is shown that the robust optimal solution to such a problem can be obtained by solving a linear program. Thus a tractable algorithm is given for robust time-optimal path-tracking control under confined torque.

Characterization of force and torque interactions during a simulated transgastric appendectomy procedure.

We have developed an instrumented endoscope grip handle equipped with a six-axis load cell and measured forces and torques during a simulated transgastric natural orifice translumenal endoscopic surgery appendectomy procedure performed in an EASIE-R ex vivo simulator. The data were collected from ten participating surgeons of varying degrees of expertise which was analyzed to compute a set of six force and torque parameters for each coordinate axis for each of the nine tasks of the appendectomy procedure. The mean push/pull force was found to be 3.64 N (σ = 3.54 N) in the push direction and the mean torque was 3.3 N · mm (σ = 38.6 N · mm) in the counterclockwise direction about the push/pull axis. Most interestingly, the force and torque data about the nondominant x and z axes showed a statistically significant difference (p < 0.05) between the expert and novice groups for five of the nine tasks. These data may be useful in developing surgical platforms especially new haptic devices and simulation systems for emerging natural orifice procedures.