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This paper presents a detailed methodology to optimally synthesize links' lengths of planar Crank-Rocker (C-R) mechanism to achieve a targeted design with definite transmission angle deviation. Analytical and graphical proposed methodologies are applied to three different case studies; each satisfies a definite case (task). The analytical methodology is based on deducing six design equations with equality constraints, which represent relations between the desired case conditions and the mechanism's lengths. Meanwhile, deflection and transmission angles; the time ratio limits or output angular stroke can be easily obtained. Furthermore, optimal synthesized results can fulfil any definite case requirements which can be represented using the corresponding six deduced equations. The optimal charts are presented to quickly obtain the optimal (C-R) mechanism's lengths, which are achieving the targeted transmission angles deviations. Consequently, the designers can easily select optimal synthesized crank-rocker mechanisms' lengths, instead of time consuming of optimization calculations. Also, this paper presented a fast-graphical methodology to directly obtain an optimal synthesized (C-R) mechanism's lengths. This methodology requires only identifying the design case related to the chosen mechanism class and the desired transmission angle deviations through giving the minimum and maximum transmission angles (γmin and γmax). Moreover, a direct relation between the mini-max transmission angle deviations, the (C-R) mechanisms classes and the performance parameters can be presented. Hence, this facilitates the specialists' mission in designing (C-R) mechanisms for special uses as driving conveying, screening and shaking mechanisms. [ABSTRACT FROM AUTHOR]

The ankle is formed by several joints, and it is the union of the lower leg with the foot. Its main function is to perform dorsiflexion and plantar flexion movements. Many people are affected by ankle problems. These problems can be due to simple factors, but they can also be a sign of a more serious impairment that can lead to the need for ankle rehabilitation. Thus, this paper presents a novel, fairly simple nonmotorized device for ankle rehabilitation. The design of the novel device is based on the crank–rocker mechanism, activated by the patient's upper limb, allowing the execution of the ankle flexion range. The dimensions of the device were found using a differential evolution algorithm considering the ankle movement limits, the link stress, and singularity configurations. Graphic simulations were performed to validate the mathematical model. A prototype was constructed, and the angular ankle movement was verified. The device is easy to operate and low-cost, and in the future, it may be a tool for ankle rehabilitation. [ABSTRACT FROM AUTHOR]

In this study, a new optimization approach is introduced to reduce vibration exerted on a double crank-rocker mechanism. A dynamic analysis based on planar methods of this mechanism is suggested, and formulation of shaking forces and shaking moments inducing vibration on this system is presented. A two-step optimization technique is suggested to study system sensitivity to the components of shaking forces and moments to enhance the mechanismâs balancing process. This leads to identification of the most dominant parameters which are then used to formulate the objective functions of effective optimization. Each objective function is studied for each individual case, after which the outcome results of the mechanismâs balancing optimization are introduced and discussed.

The ankle is formed by several joints, and it is the union of the lower leg with the foot. Its main function is to perform dorsiflexion and plantar flexion movements. Many people are affected by ankle problems. These problems can be due to simple factors, but they can also be a sign of a more serious impairment that can lead to the need for ankle rehabilitation. Thus, this paper presents a novel, fairly simple nonmotorized device for ankle rehabilitation. The design of the novel device is based on the crank–rocker mechanism, activated by the patient’s upper limb, allowing the execution of the ankle flexion range. The dimensions of the device were found using a differential evolution algorithm considering the ankle movement limits, the link stress, and singularity configurations. Graphic simulations were performed to validate the mathematical model. A prototype was constructed, and the angular ankle movement was verified. The device is easy to operate and low-cost, and in the future, it may be a tool for ankle rehabilitation.

In this study, a new optimization approach is introduced to reduce vibration exerted on a double crank-rocker mechanism. A dynamic analysis based on planar methods of this mechanism is suggested, and formulation of shaking forces and shaking moments inducing vibration on this system is presented. A two-step optimization technique is suggested to study system sensitivity to the components of shaking forces and moments to enhance the mechanism's balancing process. This leads to identification of the most dominant parameters which are then used to formulate the objective functions of effective optimization. Each objective function is studied for each individual case, after which the outcome results of the mechanism's balancing optimization are introduced and discussed. [ABSTRACT FROM AUTHOR]

This paper presents a detailed methodology to optimally synthesize links' lengths of planar Crank-Rocker (C-R) mechanism to achieve a targeted design with definite transmission angle deviation. Analytical and graphical proposed methodologies are applied to three different case studies; each satisfies a definite case (task). The analytical methodology is based on deducing six design equations with equality constraints, which represent relations between the desired case conditions and the mechanism's lengths. Meanwhile, deflection and transmission angles; the time ratio limits or output angular stroke can be easily obtained. Furthermore, optimal synthesized results can fulfil any definite case requirements which can be represented using the corresponding six deduced equations. The optimal charts are presented to quickly obtain the optimal (C-R) mechanism's lengths, which are achieving the targeted transmission angles deviations. Consequently, the designers can easily select optimal synthesized crank-rocker mechanisms' lengths, instead of time consuming of optimization calculations. Also, this paper presented a fast-graphical methodology to directly obtain an optimal synthesized (C-R) mechanism's lengths. This methodology requires only identifying the design case related to the chosen mechanism class and the desired transmission angle deviations through giving the minimum and maximum transmission angles (min and max). Moreover, a direct relation between the mini-max transmission angle deviations, the (C-R) mechanisms classes and the performance parameters can be presented. Hence, this facilitates the specialists' mission in designing (C-R) mechanisms for special uses as driving conveying, screening and shaking mechanisms. [ABSTRACT FROM AUTHOR]

Film-mulching cultivation technology could significantly improve the growth condition of crops and increase the economic benefits of agricultural production. However, the residual film in soil is very difficult to degrade, and there is no effective recovery method, resulting in the amount of residual film in farmland soil gradually increased. The residual film currently has a serious impact on the ecological environment of farmland soil. To solve this problem, domestic scholars have devised a variety of residual film collectors. The design of film removing device was one of the key points in the development of the residual film collector. However, the existing residual film collectors mainly adopts the structure of pneumatic, telescopic rod tooth and rotary scraper, which could easily cause secondary winding of residual film during the film removing process. Thus, a film removing device of clamping finger-chain type for residual film collection was designed in this study. The device was consisted of scraper assembly, crank-rocker mechanism and film-impurity separation mechanism, which could complete the work of film removing, film-impurity separation, and film transport at one time. In order to increase the contact times between the finger and the scraper when the clamping finger-chain moved upward, a double-layer arrangement structure of scraper was adopted in the scraper assembly, and the structural parameters were designed through the analysis of the operation process. The ADAMS software was used to simulate and analyze the motion trajectory of the endpoint of the scraper, and the length of each rod and the mounting angle of the crank-rocker mechanism were designed. Through the force analysis of residual film, the mounting position of the crank-rocker mechanism was determined. Through the kinematics analysis, the maximum value of the angular speed ratio between the upper film collecting wheel and the crank when the fingers were not scratched was obtained. In order to achieve the film-impurity separation and film transport, a film-impurity separation mechanism with reciprocating swing type was designed, and the structural parameters of related components were designed based on the operation mechanism analysis and performance tests. The field experiments results showed that the residual film recovery rate was 93.12%, the film removing rate was 98.2%, and the impurity rate was 16.08%, when the travel speed of the collector was 4.5 km/h, the width of scraper was 100 mm, the horizontal mounting distance between the rotation center of crank and the center of upper film collecting wheel was 290 mm, the vertical mounting distance between the rotation center of crank and the center of upper film collecting wheel was 200 mm, the angular speed ratio between the upper film collecting wheel and the crank was 0.5, and the mounting distance of the bar in film transport sieve was 50 mm, The results indicated that the film removing device could meet the field operation requirements of the residual film collector. The research can provide the basis and reference for the development of relevant residual film collector. [ABSTRACT FROM AUTHOR]

The tufting carpet machine has multiple sets of linkage mechanism,and the movement of the linkage mechanism directly affect the quality of the weaving and efficiency of the loom. Taking the needle rod mechanism of tufting carpet machine as the research object,by using ADAMS simulation software,a simple model of tufting carpet machine needle rod mechanism is built and the dynamics simulation analysis is carried out. The diagram of reaction of supports,working retard moment and the balance torque on the crank of each connection point on the crank- rocker mechanism of the tufting needle rod mechanism is obtained. And comparing with the diagram of experimental data which is by numerical analysis that to verify the correctness of the dynamic simulation analysis,and a basis for the optimization design of tufting needle rod mechanism is provided.

Canopy shaking is one of the most commonly used techniques for mechanical harvesting of citrus fruits in orange juice industry. However, tree damage and low harvesting efficiency are the top concerns of growers in adopting the existing harvesting equipment on a large scale. The purpose of this research was to develop a novel canopy shaking system to minimize tree damage and maximize fruit removal for mechanical citrus harvesting. In this study, a two-section canopy shaker composing of top and bottom shaking systems mounted on two rotating drums was proposed and developed. It was configured with two sets of flexible bow-shaped shaking rods in a staggered distribution, which can shake the top and bottom zones of the tree canopy independently. The shaking system was designed based on a linked crank-rocker mechanism. Kinematic simulation analysis was conducted to verify the quick return characteristics and differential properties of this mechanism. Vibration test showed that the frequency of the shaking rod could be adjusted within a range of 1.1-8.8 Hz related to hydraulic motor speeds. The field tests of the shaking system with an average frequency of 4.7 Hz achieved a fruit removal percentage of 82.6% and tree damage rate of 5.4% under a tractor speed of 3 km/h. By contrast, the combined shaking frequency of 4.7 Hz & 4.1 Hz of the canopy shaker produced less tree damage with a percentage of 3.9%. This study indicated that the two-section canopy shaker with an optimized frequency combination could be adaptable to the different zones of the tree canopy, and obtain lower tree damage and higher fruit removal percentage. [ABSTRACT FROM AUTHOR]

Based on the requirements of Shanxi College Students' Comprehensive Ability Competition in Engineering Training, a car which converts gravitational potential energy into kinetic energy and automatically detours 8-track is designed. According to the competition requirements, the structure of the car is designed. First, we simulate the best 8- shaped track using Matlab software, and then use the track to determine the car's wheel diameter and gear mechanism's transmission ratio. Furthermore, we design the car's steering system through a combination of incomplete gear and crank rocker mechanism. The car detours 8-shaped track's non-circular section and circular section when incomplete gear is in toothed portion and the non-toothed portion periodicity. Finally, UGNX software is used for three-dimensional modeling, assembling and motion simulation of the car constituted bodies. After achieving the desired effect from the simulation, the car is manufactured and debugged. The practice tests verify the rationality of the mechanism. [ABSTRACT FROM AUTHOR]

A novel live animal screening machine was designed to solve the screening issue for yellow mealworm and frass in the artificial breeding production process. The control system based on semantic similarity computation, operation mode, overall structure, working principle and main structural parameters of the machine were designed and optimized in this study. Furthermore, the kinematics mathematical model of the crank-rocker of shaking and the screening mechanism was analysed. In addition, motion analysis of shaking and screening mechanism was conducted, and then the displacement, velocity and acceleration curves of pendulum rod and screening body were obtained. Finally, the structure design and motion simulation of all parts were finalized to confident with the design. The prototype performance tests of the yellow mealworm screening machine show that machine has a reasonable structure, convenient operation, good screening effect and high working efficiency. This study provides a new thought for screening yellow mealworms. [ABSTRACT FROM AUTHOR]

In this scheme, after assessing the requirements of electronic stability systems, in addition to a sensor set including a yaw-rate sensor, an accelerometer, a thermal sensor and an speed sensor, a 32-bit microcontroller based control system was designed in which the major necessities for data collecting and rapid processing of such a typical system could be performed. Furthermore, hardware capabilities for implementing the control algorithms using appropriate actuators when installing on a mechanical system was considered. Simultaneously, system is able to connect through the serial interfaces to the more powerful computers and processors for more complicated analysis. Moreover, for evaluating the performance of the designed system, a mechanical test-bench was designed and the obtained data was compared with the computer simulations. Results show that the designed inertial measurement system meets the required specifications of speed, efficiency and reliability. [ABSTRACT FROM AUTHOR]