Slider Crank Research Articles

Design of Smart Phone Organizer based on OpenMV

Inappropriate use of cell phones can affect the normal order of the lecture, and reasonable control of cell phone use in the classroom can improve students' learning efficiency. This project designs a cell phone smart organizer with a circumferential distribution structure. It uses a special crank slider mechanism to make the cell phone in the organizer only perform the circumferential translational movement, preventing collision damage to the cell phone. Arduino is used for control, and the servo drives the crank rotation. Based on the OpenMV module, the cell phone can be accessed through face recognition, which enhances the security and operability of the organizer. At the same time, with the LCD, the face recognition result is dynamically displayed, which is convenient for human-computer interaction.

Augmented Lagrangian index-3 semi-recursive formulations with projections

MBSLIM (Multibody Systems at Laboratorio de Ingenieria Mecanica) multibody library includes some global formulations for the dynamics and sensitivity analysis of multibody systems. The extension of the library to accommodate topological formulations in relative (joint) coordinates and their implementation are going to be described in two separate works, this one being devoted to dynamics and the second one to a sensitivity analysis. With this extension in the scope, some topological semi-recursive formulations derived in the past are revisited, generalized and reformulated. The need for generalization of the previously published formulations was detected because the equations proposed were not general enough to be integrated in an all-purpose multibody library in natural coordinates like MBSLIM, especially because both set of coordinates need to coexist, the definition of the mechanisms has to be the original one and the library has to be automatic and all the existing models have to work with the new approach. Moreover the new solver takes advantage of some problems solved in natural coordinates, like the initial position and initial velocity problems for closed-loop systems. Finally, to test the new equations, two benchmark problems are presented and their results compared: a spatial slider–crank mechanism and a buggy vehicle model.

Simulation Module of Crank Rocker Mechanism Based on GTENG Engine

GTENG engine technology is a complete set of real-time 3D engine that is mainly applied to the simulation field of engineering equipment. Crank rocker mechanism is common in engineering equipment. This paper analysed the evolution of crank slider mechanism, and two motion types and parameter compute of crank rocker mechanism. The design of CCrankRocker, associated mesh scene node and using coordinate system all were discussed. Further, compute way of motion simulation of the four components required for CCrankRocker was emphasized. The paper indicated that is needs set firm parent-child relationship between bar and slider when modeling in 3DS MAX, and enumerated some legends of the origin of each node and the directing of axis in coordinate system of crank rocker mechanism. Finally, the use of crank rocker mechanism module was illustrated by analysing the main function of Load function correlating model nodes with classes, and the motion simulation example of bucket rocker mechanism was given with partial program. The application shows that the simulation of crank rocker mechanism based on GTENG engine is smooth, practical and wide.

CaseCrawler: A Lightweight and Low-Profile Crawling Phone Case Robot

The CaseCrawler is a lightweight and low-profile movable platform with a high payload capacity; it is capable of crawling around carrying a smartphone. The body of the robot resembles a phone case but it has crawling legs stored in its back. It is designed with a deployable, in-plane transmission that is capable of crawling locomotion. The CaseCrawler's leg structure has a knee joint that can passively bend only in one direction; this allows it to sustain a load in the other direction. This anisotropic leg allows a crank slider to be used as the main transmission for generating the crawling motion; the crank slider generates a motion only within a 2D plane. The crank slider deploys the leg when the slider is pushed and retracts it when pulled; this enables a low-profile case that can fully retract the legs flat. Furthermore, by being restricted to swinging within a plane, the hip joint is highly resistant to off-axis deformation, this results in a high payload capacity. As a result, the CaseCrawler has a body thickness of 16 mm (the transmission without the gearbox is only 1.5 mm) and a total weight of 22.7 g; however, it can carry a load of over 300 g, which is 13 times its own weight. To show the feasibility of the robot for use in real-world applications, in this study, the CaseCrawler was employed as a movable platform that carries a 190 g mass, including a smartphone and its cover. This robot can crawl around with the smartphone to enable the phone to charge itself on a wireless charging station. In the future, if appropriate sensing and control functions are implemented, the robot will be able to collect data or return to the owner when needed.

Analysis of Power Generating Speed Breaker Based on Modified Slider Crank Mechanism

Analysis of Power Generating Speed Breaker Based on Modified Slider Crank Mechanism

Fundamental study of centrifugal pendulum vibration absorber with slider crank chain to suppress the torsional vibration in automatic transmission for cars

Fundamental study of centrifugal pendulum vibration absorber with slider crank chain to suppress the torsional vibration in automatic transmission for cars

DEVELOPMENT AND APPLICATION OF A COMPUTER PROGRAM FOR FOUR-BAR LINKAGE AND SLIDER-CRANK MECHANISMS

Complex mathematical problems have been solved with the aid of software application to obtain reliable results. The positional kinematic analysis of a slider crank mechanism involves computation of the motion parameters: linear displacement, velocity and acceleration of the slider; and angular velocity and angular acceleration of the connecting rod for every 300 variation of the crank angle. This study aimed to develop a customized software which can be used to efficiently analyse a given design of a four-bar and a slider-crank mechanisms. A program was written using VB (Visual Basic) programming language for the equations of angular velocities and angular acceleration of the coupler and follower for the four-bar linkage and the linear velocity and acceleration of the piston for the slider crank mechanism. The program was tested with different parameters for the mechanisms and the solutions compared with the results from manual calculations. The findings revealed that there were no differences (p ≤ 0.05) between the results using the program and manual calculations, which imply the accuracy of the program. It can be concluded that the program could be used to solve problems of four- bar linkage and slider-crank mechanisms.

Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint

This paper proposes a variable stiffness joint based on a symmetrical crank slider mechanism (SCM-VSJ). Firstly, the mechanical design and the working principle of the variable stiffness joint is described, and its stiffness regulation characteristics are studied. Secondly, the dynamical model of variable stiffness joint including joint motor, harmonic reducer and stiffness adjustment motor is established, in addition, the transmission mechanism of the crank slider mechanism and the elastic deformation of the spring bar are considered in the dynamic modeling. Finally, in order to control the dynamic stiffness of the variable stiffness joint in real time, a kind of improved PID (proportional-integral-derivative) control algorithm based on feed-forward and feedback closed-loop is proposed on the basis of the existing dynamical model, and the simulation analysis of real-time tracking control of dynamic stiffness for sinusoidal wave expected stiffness signal and random expected stiffness signal is carried out respectively. The research shows that the real-time stiffness control of SCM-VSJ can be realized effectively, and during the stiffness adjustment process, the output torque of the stiffness adjustment motor will be affected by the elastic deformation of the spring bar.

Design and Modeling of Cereal Crop Reaper Machine

Harvesting by using traditional method is time consuming; it needs much labor force and result in much grain loss. For developing nations like Ethiopia, importing combine harvester is too expensive and not affordable for small scale farmers. The aim of this project was to design and model cereal crop reaper machine that is easily available and operated by small scale farm holders. The designed reaper was manually guided and powered with diesel engine for cutting cereal crop stems. With the help of pulley-belt arrangement, drive power is transmitted from engine to gear mounted shafts. A bevel gear arrangement is used to transmit motion at certain angle. One end of bevel gear shaft was connected to slider crank mechanism which converts rotary motion of shaft into reciprocating motion of cutter bar. Reciprocating cutter bar slides over fixed bar and created scissoring action between cutter blades which are responsible for cutting the crop stems. Integrating mechanism consist of flat belt with collecting lugged plates bolted on it. This machine can give a cost saving of 99.89 USD/hectare. This means one farmer can save 99.89 USD/hectare compared to manual harvesting machine.

Force transmission performance for a novel deformation wheel with crank slider mechanism

This study aims to analyze the force transmission characteristics of a novel wheel composed of a mechanism of planar crank slider with virtual constraints. The principle of kinematic inversion is applied to analyze the force transmission characteristics of deformable wheel in an innovative way. First, the structural design of deformable wheel and diagram of mechanism motion are presented. Second, the model of force transmission characteristic of deformable wheel is established on the basis of principle of kinematic inversion. Third, the force changes in the two pairs of springs in the deformable wheel are investigated using MATLAB and ADAMS. Finally, the force transmission performance between the deformable and elastic wheel is compared. Results show that the possibility of a flat wheel can be avoided under severe geological conditions, and the force transmission performance is better than that of the traditional elastic wheel. The results of this study can provide theoretical guidance in designing a novel nonpneumatic wheel.

Numerical and Dynamic Errors Analysis of Planar Multibody Mechanical Systems With Adjustable Clearance Joints Based on Lagrange Equations and Experiment.

For theoretical study and engineering application, it is necessary to provide an accurate and simple dynamical model to simulate the multibody mechanical systems with clearance joints and it is also the subject of this article. Based on Lagrange equations of the first kind, a different numerical methodology, the length and rotation angle of the clearance joints are looked as independent coordinates for the first time, is presented in detail. The slider-crank mechanism, with a single or double adjustable revolute clearance joints, is used as a numerical model. A test rig and a simulink model, fully in accordance with the numerical model, are used to measure the velocity, displacement, and acceleration. The numerical results tally with experimental and simulink results reveal that the new methodology, presented in this paper, provides a correct approach to build the dynamical equations of mechanism with clearance joints. Lyapunov exponent is used to analyze the motion status, chaotic or periodic, of the slider. Based on data points, mean absolute deviation (MAD) is applied to judge the dynamical errors, displacement, velocity, and acceleration, of the slider due to clearance joints. With the help of Lyapunov exponent and MAD, the results indicated that various clearance sizes and drive speeds can change the dynamical behaviors of the slider, which is complex but can be predicted in some way.

Design and test of the crank slider mechanism feeding type rubber rotary cutting machine

Aiming at the problems such as low processing efficiency and high labor intensity when the rubber block was processed, a new type of crank slider mechanism feeding style rubber rotary cutting machine was designed with the help of computer. Starting with the two major processing steps of pushing and cutting the rubber block, an offset crank slider mechanism was used to push the rubber block in order to improve the processing efficiency of the rubber block. The V-belt was driven by the motor to rotate the circular saw blade, and the ball screw drove the rubber cutting table to make the rubber block perform reciprocating linear motion. The synthesis of the above two motions could achieve efficient cutting of the rubber block. Taking the needs of the rubber block cutting process into account, the flat belt width of the transmission rubber block was designed to be 355 mm, so that the machine had a good adaptability to rubber blocks. The modal simulation analysis determined that the optimal thickness of the circular saw blade was 3 mm and the optimal diameter of the circular saw blade was 500 mm. And the static finite element simulation analysis results also showed that the circular saw blade with this set of parameters had good strength and stiffness. After the orthogonal test was conducted on the prototype of crank slider mechanism feeding style rubber rotary cutting machine, the test results showed that the machine could cut 15 rubber blocks averagely per minute and each test produced less than 10 g rubber residue. In a word, the designed machine not only improved the cutting efficiency, but also met the demand for green and efficient processing of the modern agricultural products.

A new model of the contact force for the collision between two solid bodies

A collision between two bodies is a usual phenomenon in many engineering applications. The most important problem with the collision analysis is determining the hysteresis damping factor or the hysteresis damping ratio. The hysteresis damping ratio is related to the coefficient of restitution. In this paper, an explicit expression is determined for this relation. For this reason, a parametric expression is considered for the relation between the deformation and its velocity of the contact process. This expression consists of two unknown constants. Using the energy balance, a new explicit parametric expression between the hysteresis damping factor and the coefficient of restitution is derived. For determining the unknown constants, the root mean square (RMS) of the hysteresis damping ratio of this new expression with respect to the numerical model is minimized. This new model is completely suitable for the whole range of the coefficient of restitution. So, the new model can be used in the hard and soft impact problems. Finally, three numerical examples of two colliding bodies, the classic bouncing ball problem, the resilient impact damper, and a planar slider–crank mechanism, are presented and analyzed.

Development of medical physio device for stroke patients

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.

Kinematics and control approach for deployable and reconfigurable rigid bar linkage structures

Deployable building structures able to respond to varying environmental and functional conditions through shape transformations aim at an interactive and optimized behaviour towards sustainability of our built environment. A kinematics approach applied to a lightweight linkage structure is presented that builds upon aspects of flexibility and controllability through modularity and simple actuation requirements. The principal planar structure consists of serially connected rigid members. One side of the linkage is pinned to the ground and the other side is pinned to a sliding block. A single linear motion actuator detached from the structural body, acts on the sliding block, while all intermediate joints are equipped with brakes. The reconfiguration approach involves the stepwise selective locking of joints, to define a generic one degree-of-freedom (1-DOF) ‘effective crank–slider’ (ECS) mechanism. The approach is examined through simulation studies followed by hardware implementation on a small scale 1:10 prototype.

Nonlinear Stiffness Analysis of Spring-Loaded Inverted Slider Crank Mechanisms With a Unified Model

Abstract 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.

An approach for dynamic analysis of planar multibody systems with revolute clearance joints

Clearance is inevitable for manufacture and assembly in the revolute joints of multibody systems. Excessive value of joint clearance will lead to the poor dynamic performance of mechanism, namely noise, vibration and fatigue failure. This paper presents the development of a dynamic model for planar multibody systems with clearance joints. Based on the continuous contact law, the contact force model proposed by Lankarani and Nikravesh is employed to describe the contact–impact phenomenon between pin and hole. And, the incorporation of the friction influence on revolute joint clearance is conducted by a modified friction force model. According to the geometric relationship between contact elements, the kinematics of the multibody systems is mapped into the global coordinate systems. Additionally, an experimental test platform is set up whereby a slider–crank mechanism with two clearance joints is used as an example to demonstrate the correctness and effectiveness of the proposed approach. Finally, the effects of joint clearance on the dynamic characteristics of planar multibody systems are investigated.

Modelling and simulation of coupled multibody systems and granular media using the non-smooth contact dynamics approach

Multibody models are often coupled with other domains in order to enlarge the scope of computer-based analysis. In particular, modeling multibody systems (MBSs) in interaction with granular media is of great interest for industrial process such as railway track maintenance, handling of aggregates, etc. This paper presents a strong coupling methodology for unifying a multibody formalism using relative coordinates and a discrete element method based on non-smooth contact dynamics (NSCD). Both tree-like and closed-loop MBSs are considered. For the latter, the coordinate partitioning techniques is applied in the NSCD framework. The proposed approach is applied on the slider–crank mechanism benchmark. Results are in very good agreement with results obtained with other techniques from the literature. Finally, a multibody model of a tamping machine is coupled to a discrete element model of railway ballast in order to analyse efficiency of track maintenance. This application demonstrates that the dynamics of the machine must be taken into account so as to estimate the performance of the maintenance process correctly.

Dynamical response of a pendulum driven horizontally by a DC motor with a slider–crank mechanism

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.

Adaptive self-recurrent wavelet neural network and sliding mode controller/observer for a slider crank mechanism

Adaptive self-recurrent wavelet neural network and sliding mode controller/observer for a slider crank mechanism