Connecting Rod Structure Research Articles

Structure Design and Path Planning for Cleaning Manipulator

Robots can replace people to complete many complex, and repetitive tasks, and can also replace people to work in dangerous and toxic and harmful environments. At present, most of the car cleaning methods are manual cleaning, which is time-consuming and laborious. It is also easy to damage the car surface and dirt will endanger the health of staff. The car cleaning robot can replace people to clean. The structure and cleaning path of the cleaning manipulator have an important impact on the cleaning efficiency. The paper designs the structure of the cleaning manipulator and plans its cleaning path. Firstly, the functions of the studied manipulator are analyzed through investigation; Determine the overall structure of the cleaning manipulator according to the required functions to ensure that the car can be cleaned in all directions; Secondly, carry out detailed structural design for the 6-DOF manipulator, complete the clamping of rags and other cleaning tools through the connecting rod structure, and assemble rollers on both sides of the connecting rod to ensure that the robot can effectively complete the cleaning of the car, and carry out digital 3D modeling; Finally, the cleaning path of the manipulator is planned in the MATLAB environment to ensure the smooth motion of the robot. The digital motion simulation of the manipulator is completed by solving the forward.

Optimization design of titanium alloy connecting rod based on structural topology optimization

Purpose The purpose of this paper is to realize the lightweight of connecting rod and meet the requirements of low energy consumption and vibration. Based on the structural design of the original connecting rod, the finite element analysis was conducted to reduce the weight and increase the natural frequencies, so as to reduce materials consumption and improve the energy efficiency of internal combustion engine. Design/methodology/approach The finite element analysis, structural optimization design and topology optimization of the connecting rod are applied. Efficient hybrid method is deployed: static and modal analysis; and structure re-design of the connecting rod based on topology optimization. Findings After the optimization of the connecting rod, the weight is reduced from 1.7907 to 1.4875 kg, with a reduction of 16.93%. The maximum equivalent stress of the optimized connecting rod is 183.97 MPa and that of the original structure is 217.18 MPa, with the reduction of 15.62%. The first, second and third natural frequencies of the optimized connecting rod are increased by 8.89%, 8.85% and 11.09%, respectively. Through the finite element analysis and based on the lightweight, the maximum equivalent stress is reduced and the low-order natural frequency is increased. Originality/value This paper presents an optimization method on the connecting rod structure. Based on the statics and modal analysis of the connecting rod and combined with the topology optimization, the size of the connecting rod is improved, and the static and dynamic characteristics of the optimized connecting rod are improved.

Thermally coupled structural analysis of a connecting rod obtained by powder metallurgy

The paper is structured in two parts, the first part is dedicated to modeling and numerical simulation in dynamic regime of the motor mechanism from a 4-stroke combustion engine and the second part, to finite element method analysis in thermally coupled structural behavior of sliding bearings. The bearings in the connecting rod structure are obtained by Powder Metallurgy. It is described the procedure for the experimental determination of the material properties of the parts made of metallic powders, which are required as input data for modeling in an integrated system of the sintering process coupled with the structural analysis of the engine assembly.

Kinematics analysis and experiment of a lily picking mechanical arm

A lily flower is a medicinal plant, which has been widely used in the Chinese medicine industry in recent years. According to the rapid picking of the lily flower, a scheme of the mechanical arm picking structure was designed, and the system with an end effector, manipulator and control system was used. The mechanical arm adopts a three-stage connecting rod structure. Through the lily plant growth of more than about 85% <50 cm characteristics of the mechanical arm were picked up from the top to bottom operation strategy. Based on this, the kinematics model of the picking robotic manipulator is designed. The kinematic equation of the manipulator is demonstrated by a DH deducing method. The kinematics simulation of the manipulator is carried out by MATLAB. The mechanical arm kinematics and picking experiments were carried out in the experimental field in a natural environment by the robotic physical machine platform. The results showed that the manipulator position error from the end of the arm was <12 mm and the picking success rate was 83.33%.

Biped Robot Gait Planning Based on 3D Linear Inverted Pendulum Model

In order to optimize the biped robot’s gait, the biped robot’s walking motion is simplify to the 3D linear inverted pendulum motion mode. The Center of Mass (CoM) locus is determined from the relationship between CoM and the Zero Moment Point (ZMP) locus. The ZMP locus is planned in advance. Then, the forward gait and lateral gait are simplified as connecting rod structure. Swing leg trajectory using B-spline interpolation. And the stability of the walking process is discussed in conjunction with the ZMP equation. Finally the system simulation is carried out under the given conditions to verify the validity of the proposed planning method.

Cyber-physical Modeling of High Speed Machining of Flexible Materials

Due to the structure characteristics of flexible materials, it will easily be deformed in the cutting process and thus the cutting interface be destroyed, resulting in low-quality cutting parts. Based on the cutting process of flexible leather substance, this paper attempts to develop a new high speed vibration cutting mechanism for flexible materials. Research will be on the vibration cutting method for flexible materials, and then a high speed vibration cutting head module will be designed according to motion transformation principle of eccentric shaft and connecting rod structure. Corresponding tests and Experiments are carried out and as the result, the vibration cutting frequency is up to 20,000 times/min, with the angle error within ±1.5°. The cutting speed can achieve 120 cm/s, and work noise < 80db.

A Joint Physical Constraints Avoidance Method for Inverse Kinematics Problem of Redundant Humanoid Manipulator

There are innumerable inverse kinematics solutions that can meet the demand of end-effector position and orientation for the redundant humanoid manipulator. Also each manipulator joint has its physical constraints for the connecting rod structure and figuration design. In order to make the inverse kinematics solution away from the joint position limitation maximization, an algorithm that combines geometry method and numerical iterative method is proposed to solve the inverse kinematics problem of redundant humanoid manipulator(8-DOF). Based on the derived geometric formula of the inverse kinematics problem, the "Away Limitation Level" of the humanoid manipulator is adopted as fitness function and optimization goal, and then particle swarm optimization(PSO) is used to search for the optimal combination of the redundant joint, and the optimal inverse kinematics solution can be obtained in this method. The proposed method can not only solve the multiple inverse kinematics solutions problem of the redundant humanoid manipulator, but also have some advantages, i.e., the solution no theoretical error, fast solving speed and the large margin away from the joint position limitation. Numerical simulation results demonstrate the effectiveness of this algorithm.

Failure Process and Mechanism Analysis for the Connecting Rod of Diesel Engine

The operational fault of diesel engine caused by losing the required function in running is a random phenomenon. It needs to collect a large number of fault samples and reliability data to reveal the fault occurrence rule and describe it with mathematical method. In this paper, the fault law and mechanism of the engine connecting rod were researched by the physical and chemical analysis of the fault samples. The fault reasons and the fault mechanism can be found through the analysis of the organization structure, material properties, process features, heat treatment process and other reliability information of the fault sample. It can provide scientific basis for the failure exclusion as well as the optimization and improvement of connecting rod structure.

Finite Element Analysis and Multidisciplinary Design Optimization of Diesel Engine Connecting Rod Based on ISIGHT

Based on the multidisciplinary design optimization method and the MDO software ISIGHT, the 16PA6STC diesel engine connecting rod was taken to the model, used the Pro/engineer software to build the 3D model of connecting rod. The software ANSYS and Nastran was taken to complete the static analysis and modal analysis to get the maximum equivalent stress and the first and second modal frequencies. the software including Pro/Engineer、ANSYS、Nastran, was combined on the ISIGHT to complete the structural optimization work on the condition of restrain the stress and modal of the connecting rod, to explore the application of the MDO design method in the diesel engine connecting rod structure optimization field, offer a reference for the further improvement design study.