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This paper investigates the forward and inverse kinematics in screw coordinates for a planar slider-crank linkage. According to the definition of a screw, both the angular velocity of a rigid body and the linear velocity of a point on it are expressed in screw components. Through numerical integration on the velocity solution, we get the displacement. Through numerical differential interpolation of velocity, we gain the acceleration of any joint. Traditionally, position and angular parameters are usually the only variables for establishing the displacement equations of a mechanism. For a series mechanism, the forward kinematics can be expressed explicitly in the variable of position parameters while the inverse kinematics will have to resort to numerical algorithms because of the multiplicity of solution. For a parallel mechanism, the inverse kinematics can be expressed explicitly in the variable of position parameters of the end effector while the forward kinematics will have to resort to numerical algorithms because of the nonlinearity of system. Therefore this will surely lead to second order numerical differential interpolation for the calculation of accelerations. The most prominent merit of this kinematic algorithm is that we only need the first order numerical differential interpolation for computing the acceleration. To calculate the displacement, we also only need the first order numerical integral of the velocity. This benefit stems from the screw the coordinates of which are velocity components. The example of planar four-bar and five-bar slider-crank linkages validate this algorithm. It is especially suited to developing numerical algorithms for forward and inverse velocity, displacement and acceleration of a linkage.

The paper introduces solid edge 3D model of synthesized geared slider crank mechanism. The synthesized mechanism exhibits the features of variable topology mechanism. This mechanism is modeled in solid edge software and presented. The gear connected to the crank provides the possibility of using it as an input and as well as output to the mechanism. The mechanism showcases the single input to multiple output variable topology features.

The paper focuses on synthesis of slider crank mechanism consisting of a single gear as a part of input and output of the mechanism. Complex number method is used as one of the synthesis criteria. This is a planar four link gear slider mechanism having one degree of freedom which is considered for synthesis using variable topology method for the task of motion generation. The mechanism consists of three revolute and one slider joints. Synthesized mechanism exhibits the features of variable topology mechanism in different modes of operation.

The slider-crank mechanism is used widely in modern industrial equipment whereby the contact-impact of a revolute clearance joint affects the dynamic behavior of mechanical systems. Combining multibody dynamic theory and nonlinear contact theory, the computational methodology for dynamic analysis of the slider-crank mechanism with a clearance joint is proposed. The differential equations of motion are obtained considering the revolute clearance joint between the connecting rod and slider. In the mechanical system, the contact force is evaluated using the continuous force model proposed by Lankarani and Nikravesh, which can describe the contact-impact phenomenon accurately. Then, the experimental study is performed whereby the numerical results are compared with the test data to validate the proposed model. Moreover, the dynamic response analysis is conducted with various driving velocities and clearance sizes, which also explains that the sensitive dependence of a mechanical system on the revolute clearance joint.

This study presents a new variation of slider-crank mechanism designed by coupling a planar and a screw groups of zero mobility. In this mechanism the rotation of the driving link converts to the motion of the end-effector along a screw path. A detailed assembling computational model of the synthesized mechanism is presented, according to which kinematic and kinetostatic (force) analyses are carried out. The obtained calculation data and the computer-aided modeling results are used in production the physical prototype of the mechanism.

Physiotherapy may be a technique for relaxing the stresses in muscles in several parts of the body. This system needs the physiotherapist supervision and a daily visit to the hospitals to be at this system we came with an answer by using simple mechanisms like slider crank mechanism, wiper and rack and pinion mechanism. With the assistance of simple robot, physio treatment is completed automatically and maybe done reception with none assistance. Moreover, Home traction devices have also meant that patients once advised by the therapist regarding the weights and duration of traction treatment are ready to apply traction themselves.

Joint clearances need to be specified for the assembly and operation of mechanisms. When the joint clearances are determined while designing, it ensures the robust operation of the mechanism. The r...

In this work, a position control in task space for slider-crank mechanisms is presented. In order to apply linear controllers it is required to linearize the mechanism dynamics at an equilibrium point. However, complete dynamic knowledge is needed and the linearization technique gives an oversimplified model that affects the control performance. In this work, it is proposed a novel method to design task space controllers without using the complete knowledge of the mechanism dynamics and linearization methods. From the extended dynamic model of parallel robots, it can be seen that the end-effector (slider) dynamics is expressed as a linear system that can be used directly for the control design instead of the complete mechanism linear dynamics. The approach requires a minimal knowledge of the mechanism dynamics and avoids linearization methods. To verify our approach, it is used pole placement and sliding mode controllers whose gains are tuned according to the slider dynamics. A linear sensor is mounted at the slider to measure its position and avoids considering noise and disturbances at links before the slider. Simulations and experiments are presented to validate our approach using two kinds of slider-crank mechanisms.

The pendulum is excited horizontally by a system of a DC motor and a slider–crank mechanism. Mathematical modeling is realistic and based on experimental rig, taking into account details concerning friction in the joints as well as realistic mass distribution in particular elements of the system. Using basic nonlinear tools as phase portraits, Poincare maps, and Fourier spectra, we report various solutions including periodic, quasi-periodic and non-periodic ones. To identify chaotic solutions, we used the 0–1 test. The simulation results were qualitatively confirmed by experiments.

In this study, mathematical models of a novel mechanism, rhombic-drive, for a two-stroke, spark ignition (SI) engine, and a two-stroke SI engine with a conventional slider-crank mechanism were performed in MATLAB software. Their performances were compared with kinematic and thermodynamic analyses. Mathematical model was conducted according to real cycle approach and some of the operating parameters such as compression ratio, swept volume, heat release time, and lambda were kept identical for both engines. Pressure, volume, temperature, heat release, heat transfer coefficient, work, piston speed, and acceleration changes were examined. Maximum in-cylinder pressure was taken at 222 degrees CA with 4,188 kPa for rhombic-drive engine while 190 degrees CA with 4,003 kPa for slider-crank mechanism engine and maximum temperature was only 39 K higher for rhombic-drive mechanism engine. Theoretical thermal efficiencies of rhombic-drive and slider-crank mechanism were 31.14% and 31.87%, respectively. Effective power of rhombic-drive mechanism engine was 2.12 kW, whereas slider-crank mechanism engine was 2.17 kW. Mechanical efficiency of rhombic-drive engine was obtained 85.89%, while this was only 86.21% for slider-crank mechanism engine.

In this paper, a real-time implementation of a second-order adaptive windowing technique for acceleration estimation is presented for a slider crank mechanism. It is shown that there are some critical parameters which should be carefully set to proper values for a satisfactory acceleration estimation. In this technique, the size of the window is automatically enlarged until the position errors will not be out of the error bands defined by the user. In order to show the effectiveness of the second-order adaptive windowing technique in real-time, a test setup composed of a slider-crank mechanism is used. In the performed tests, only the crank angle is measured via an incremental encoder having a 1024 pulse per revolution, and then, the slider acceleration is estimated by the help of some kinematic calculations using the outputs of the second-order adaptive windowing technique. The estimated acceleration results are directly compared with an acceleration sensor having a measurement range with ±6g with a nominal 0-200 Hz bandwidth attached on the slider. It is found that the root-mean-square value of the acceleration errors along the entire motion profile is at tolerable level so that this effective acceleration estimation technique could be applied to various on-line robotic applications as a soft sensor., Bu çalışmada, bir krank-biyel mekanizması için ivme tahmini için ikinci dereceden bir uyarlanabilir pencereleme tekniğinin gerçek zamanlı bir uygulaması sunulmaktadır. Doğru bir ivme tahmini için uygun değerlere dikkatlice ayarlanması gereken bazı kritik parametreler olduğu gösterilmiştir. Bu teknikte pencerenin boyutu, konum hataları kullanıcı tarafından tanımlanan hata bantlarının dışına çıkmayıncaya kadar otomatik olarak büyütülür. İkinci mertebeden uyarlamalı pencereleme tekniğinin etkinliğini gerçek zamanlı olarak gösterebilmek için krank-biyel mekanizmasından oluşan bir test düzeneği kullanılmıştır. Yapılan testlerde, devir başına 1024 darbeye sahip artımlı bir optik kodlayıcı ile krank açısı ölçülmekte olup sonrasında ikinci dereceden uyarlamalı pencereleme tekniği kullanılarak bazı kinematik hesaplamalar yardımıyla kızak uzvunun ivmesi tahmin edilmektedir. Tahmin edilen ivme değerleri, kızağa bağlı 0-200 Hz nominal bant genişliğine ve ±6g ölçüm aralığına sahip bir ivmelenme sensörü ile doğrudan karşılaştırılmaktadır. Tüm hareket profili boyunca ivme hatalarının karekök-ortalama değerinin tolere edilebilir düzeyde olduğu ve dolayısıyla bu etkin ivme tahminleme tekniğinin çeşitli çevrimiçi robotik uygulamalarda bir yumuşak sensor olarak kolaylıkla uygulanabileceği gösterilmiştir.

Balancing the torque of mechanisms designed to minimize the fluctuation of input shaft torque is an effective means of improving their dynamic performance. There are several ways of solving the problem: optimizing the distribution of the moving mass of the original mechanism; cam sub-systems that displace the balancing mass; cam-spring mechanisms; flywheels driven by noncircular gears; adding articulated dyads, linkages or redundant drivers. This paper addresses the problem of input torque compensation with the optimal connection of two identical slider-crank mechanisms. The acceleration and deceleration phases of the links of the slide-crank mechanism obviously change periodically, causing torque to fluctuate at the input shaft. The problem is how to connect two mechanisms in order to reduce the input torque. This is done by minimizing the root-mean-square value of the input torque of the combined linkages. Two schemes are considered: slider-crank mechanisms with sliders moving on the same side, and on opposite sides. The prime value of this study is that it proposes an analytically tractable solution for identifying the general dynamic properties of mechanisms. Based on the ratio of link lengths, the precise relations for optimal connection of identical slider-crank mechanisms, i.e., a connection that produces the minimum root-mean-square values of the input torque, are developed. The numerical simulations illustrate the efficiency of the suggested approach. Observations show that the best solutions from the point of view of input torque minimization are obtained for the value of the coupling angle of two mechanisms around 90 deg.

This paper presents the design, modeling, and control of a three-joint robotic fish propelled by a double-slider-crank (DSC) driven caudal fin. DSC is a mechanism that can use one direct current motor to achieve oscillating foil propulsion. Its design is guided by a traveling wave equation that mimics a fish's undulatory locomotion. After multiple tests, the robotic fish displayed good performance in mimicking a real fish's swimming motion. DSC mechanism is proven to be an effective propulsion technique for a robotic fish. With the help of another servomotor at the first joint of the fish's tail, the robotic fish can have a two-dimensional free-swimming capability. In experiments, the robotic fish can achieve a swimming speed of 0.35 m/s at 3 Hz, equivalent to 0.98 body length (BL) per second. Its steering rate is proportional to a bias angle. The DSC benefits the control of the robotic fish by independently adjusting its steering and swimming speed. This characteristic is studied in a hydrodynamic model that derives the thrust within a DSC frame. Besides the dynamic model, a semiphysics-based and data-driven linear model is established to connect bias angle to robotic fish's heading angle. The linear model is used for designing an observed-state feedback control control, and the controller has been examined in simulation and experiments.

This study presents the design and formulation of a kinematic model of a compliant slider-crank micro mechanism and its comparison with the conventional slider-crank mechanism. This work aims with Experimental Analysis of Compliant Slider Crank Micro Mechanism for kinematic performance with a parametric variation. In addition, it also deals with the study of the Mechanical advantage of compliant micro mechanisms. A formulated model is developed using the pseudo-rigid-body model (PRBM). Motion analysis software is used to show the variation in slider displacement for known input link angle. Analysis of compliant mechanism is modeled by PRBM and FEA to analyze deflection. The mechanism is modeled in Adams. The results obtained from Adams are compared with experimentation. The displacements are fairly matches to simulation results. Better displacement as compared to rigid link mechanism can be obtained for smaller angular rotation. Finite element analysis (FEA) is used to show the stress distribution inflexible component for various types of hinges like rectangular cross-section flexible hinges, circular cross-section flexible hinges. Based on stress fatigue analysis is carried for both type joint by experimentally and FEA.

The investigation analyzes effects of clearance size in revolute and spherical joints with clearance on rigid-flexible dynamic of a space slider crank mechanism by finite element method. The model of the mechanism was designed by Solidworks and then velocity, acceleration, displacement, stress and contact force were determined by finite element analysis of rigid-transient dynamic in ANSYS. The results simulation indicated that the clearance size in revolute and spherical with clearance has sightly effected on the velocity of the slider, but has significantly effected on acceleration, contact force as journal and ball impact into bearing and socket with high peaks of acceleration and contact force as presented in the graph of acceleration and contact forces. The graph outlined that journal and ball motion with three types: free light, contact and impact motion. Clearance size created deviation for the displacement of the slider from 4.29 mm to 9.87 mm and maximum principal stress increases from 8.4 MPa to 10 MPa when clearance size increases from 0 mm to 0.3 mm.

In this paper, we are interested in the effect of friction on dynamic behavior of a crank-slider mechanism with clearance joint. Due to the clearance existence in the revolute joint, it is important to choose an appropriate contact force model to analyze the dynamic response, the dynamic equations are established by combining Lagrange’s equation of the first kind with modified contact force model and LuGre friction model, the Baumgarte stabilization approach was used to improve the numerical stability. Simulation and experimental tests were carried out to verify this model. The system dynamic response hysteresis, and the more energy consumption when friction is considered in the mechanism. The influence of friction coefficient on the nonlinear dynamic characteristics of the mechanism with clearance joint is analyzed. The dynamic performance of the mechanism considering friction presents significant differences at the accelerations level. Friction plays a positive role in the stability of the system.

In this work, a position control for slider-crank mechanisms without Jacobian and joint measurements is presented. A Jacobian compensator that depends on the sign of the direction of rotation of the input link and the output link is proposed. A linear sensor is mounted at the slider to measure its position. Simulations and experiments are presented using two different Whitworth mechanisms to validate and compared the proposed approach with Jacobian-based controllers.

Varieties of robotic grippers are developed with high flexibility and multi-functional approaches. In this paper, the study and design of an innovative approach of a gripper for handling variable size, shape and weight is proposed. This paper proposes a gripper that is capable of changing the distance between its two opposite grippers. For this purpose, we use slider crank mechanism which is actuated by servo motors. The paper gives a deep understanding and the use of this type of gripper.

Kinematic dimensional synthesis is one of the essential steps during the process of design. It is classified into three tasks: function generation, path generation, and motion generation. In this paper, a design method is presented to solve the synthesis of the slider-crank mechanism for function generation based on a closed-form solution with five design parameters. The success criterion of a method used for function generation depends on the structural error function within an operational domain of the slider-crank mechanism. The structural error reduction is related to the number of design parameters utilized in mechanism synthesis, and the effective maximum number of design parameters for the slider-crank mechanism is five. In this study, the closed-form synthesis is found using three methods: precision point method, sub-domain method, and galerkin method. The system of equations is reduced to a twelfth-degree univariate polynomial equation, and thus all the available solutions are obtained. The effectiveness of this design method is tested with some examples of commonly used test functions, namely ex, sin(x), tan(x) and ln(x), using a developed computer program. This design method gives lower structural error than traditional methods in kinematics literature.

This paper investigates the factors that affect the Peak to Average Ratio (PTAR) and Mean Power (MP) for the Slider Crank Wave Energy Converter (SCWEC). The goal study is to reduce the PTAR while maximizing the MP. The PTAR needs to be reduced, because the generator that converts wave energy to electricity for the grid would become more efficient and less costly. During the process of minimizing the PTAR, the impact on MP production should be minimized, since producing usable power is the main purpose of any generation mechanism. In this paper, a few system parameters affecting the PTAR and the MP are investigated. In this analysis, these parameters are applied to multiple models of the system, and the results are recorded and compared. It is observed that the best combination of the PTAR and the MP can be determined under regular wave conditions.

A mechanism with lumped-compliance can be constructed by mounting springs at joints of an inverted slider crank mechanism. Different mounting schemes bring change in the stiffness performance. In this paper, a unified stiffness model is developed for a comprehensive analysis of the stiffness performance for mechanisms constructed with different spring mounting schemes. With the model, stiffness behaviors of spring-loaded inverted slider crank mechanisms are analyzed. Influences of each individual spring on the overall performance are characterized. The unified stiffness model allows designing mechanisms for a desired stiffness performance, such as constant-torque mechanism and variable stiffness mechanism, both being illustrated with a design example and experiments.

This paper deals the kinematic analysis of slider-crank mechanisms via the Bresse and jerk’s circles, which are two pairs of circles corresponding to different geometric loci of those coupler points with particular kinematic properties. The position vectors of the velocity, acceleration and jerk poles are determined in vector form, along with their corresponding vector fields, which are characterized by the angular velocity, acceleration and jerk of the coupler link, respectively. A specific formulation is proposed and implemented in Matlab to analyze and validate the graphical and numerical results, which can be obtained for several slider-crank mechanisms in different configurations.

The dynamic behavior of multibody systems has been widely studied. Thus, effects of imperfections such as clearance, friction and flexibility on the dynamic behaviour are dealt with various tremendous works. For a given dynamic response, the mechanism design variables needs to be defined. This identification approach is known as the mechanism synthesis. Despite all these imperfections, the mechanism should describe a precise workspace traduced by the trajectory path of the effector component. In this work, the dynamic synthesis for a multibody system with imperfections is presented. A demonstrative slider crank mechanism with a flexible connecting rod has been used for the algorithm validation. The identification approach is based on its dynamic responses such as: the slider velocity and acceleration and the transversal deflection of the flexible connecting rod. A genetic algorithm has been developed to identify its design variables. This algorithm is implemented under Matlab(c). The presented results are in great agreement with the real mechanism dimensions.

According to mechanics principle, force reduction device which is based on slider crank mechanism has been proposed. Our study developed the device’s kinematics and dynamics model, and evaluated the value of reduced force by analyzing its dynamics and kinetics deeply. Moreover, by the means of changing conditions, factors which influence force reduction had been found. For fatigue detection, we came up with an algorithm which is based on surface electromyography digital transducer and is able to monitor fatigue degree in real-time.

Piston hızının çıkarılması için, krank-pim merkezine bir kuvvet uygulanan krank-biyel mekanizmasının dinamik davranışı modellenmiştir. Dahil edilen parametrelerin çokluğu göz önüne alındığında ikinci dereceden lineer olmayan bir diferansiyel denklem şeklinde kompakt bir denklem elde etmek için topaklanmış parametre yöntemi tercih edilmiştir. Elde edilen denklemin karmaşıklığı, bir sayısal çözüm yöntemi uygulamayı zorunlu kılmıştır. Bu yolla çalışmada seçilen parametrelerin piston hızı üzerindeki etkileri incelenmiştir. Benzer şartlar altında deneysel bir model hazırlanmış ve sonuçları karşılaştırmak için testler gerçekleştirilmiştir. İki sonuç arasında elde edilen düşük hata oranları geliştirilen modelin geçerliliğini kanıtlamıştır.&nbsp, Here the dynamic behavior of slider-crank mechanism with a driving force applied at crank-pin center, has been modeled to formulate the piston speed. In view of the abundance of the parameters involved, a lumped parameter approach has been preferred to obtain a compact equation in the form of a second order nonlinear differential equation. The complexity of the resulting equation has mandated implementing a numerical solution technique by which the effects of the selected parameters on the piston speed have been investigated. Under similar conditions an experimental model has been prepared and the tests have been carried out to compare the results. Low error levels achieved in two results have demonstrated the validity of the developed model.&nbsp

The kinematical study of mechanisms is a very important matter and therefore it must be done very properly. The slidercrank mechanism is very common in engineering applications. The present paper presents an incremental numerical method used for kinematical study of the aforementioned mechanism. The kinematics of the same mechanism is performed using an analytical method. In order to validate the incremental numerical method, the results obtained by using the two methods are then compared.

This work deals with a multi-body system synthesis. A flexible slider crank mechanism has been investigated as an illustrative application. The main interest is focused on the mechanism design vari...

A general method for reliability sensitivity analysis and reliability optimization design of planar slider crank mechanism with two clearance joints was presented. A continuous contact force model considering energy dissipation was employed to estimate the contact force acting on the clearance joint. The Monte Carlo method was used to analyze the reliability sensitivity. In addition, based on the Kriging method, a surrogate model was constructed with consideration of explicit function expression. The precision and reliability of the presented method have been successfully demonstrated by numerical simulation. The results show that the number and position of clearance joint considered have a great influence on the maximum allowable displacement of the slider. The changing of the reliability sensitivity for the mean and variance of several random variables has certain regularity. Compared with the determinacy optimization design, the reliability optimization design presented here shows better dynamical performances.

This document will analyze the different effects of the length and the angular velocity affecting theperformance of the slider crank system. The performance of the slider crank system is simulated and shownusing MATLAB with reference of the model represented by a mathematical formula. The result of thesimulation is represented by several graphs, showing the relation of the length and angular velocity of therotary motion of the slider crank mechanism and the angle generated by the translational motion of theslider.

In the study, ‘monolithic’ compliant slider crank mechanism is proposed. A flexure based mechanism is developed for achieving geometric amplification of input motion. A Pseudo Rigid Body Model (PRBM) has been implemented to correlate the input force and corresponding displacement, for slider crank mechanism. The validation of the geometric model and PRBM has been carried out using finite element analysis(FEA) simulation and results are corroborated with experimental ones. Also an image based tool has been employed for preciseestimation of displacement. The motion amplification attained using compliant slider crank mechanism is a noble feature and can be employed for actuation purpose.