Optimization Of Cam Profile Research Articles

Cam Profile Design of Low-Speed Marine Diesel Engine Based on the Grey Theory

The camshaft profile is one of the important parameters of the engine, the reasonableness or otherwise of its design directly influences the engine’s power output, fuel consumption, emissions, noise and reliability. However, most existing cam profile optimization designs are based on the basic software operation, profile parameter selection and tuning lack a scientific theoretical basis. In order to address this issue, this study establishes a single valve kinematic model of the gas delivery mechanism of diesel engines by using the AVL-EXCITE Timing Drive, and performs a model-based multinomial kinematic acceleration cam profile design. Subsequently, an orthogonal design method is employed to obtain the parameter combinations that can satisfy the dynamic requirements. The research investigates the influence of cam profile design parameters (C 4, p, q, r, and s) on valve fullness, maximum jerk, cam contact stress, and valve seating force through a systematic study. Lastly, based on the grey correlation theory, a thorough analysis of the performance indices of cams with different profile parameter combinations is conducted. The optimization problem of the profile parameters with multiple performance indicators is transformed into a single-objective grey relational optimization problem, resulting in the optimal cam profile parameter combination of C4 =0.1, p=14, q=20, r=28 and s=36. The optimal method proposed in the paper is straightforward to implement and is applicable to the optimum design of cam profiles of the engine, which is of great importance for the optimal design of cam fabrication processes.

Cam profile optimization for the delivery system of an offset press

In this paper, a relatively new strategy known as unified optimization is applied to the cam profile optimization for the delivery system of an offset press by integrating the procedure of single objective optimization with ADAMS software. The proposed approach mainly consists of two parts that includes a single objective optimization procedure and a multibody dynamic model of cam–follower mechanism. For the procedure of single objective optimization, the design process starts from defining the follower acceleration profile by using a modified trapezoidal curve, then genetic algorithm is adopted to determine the evaluating indexes for the kinematic behavior of cam–follower mechanism in multiobjective optimization. Subsequently, sequential quadratic programming, which deals well with equality and inequality constrains, is selected as single objective optimized algorithm in this part. On the other hand, the dynamic simulation developed by ADAMS software is carried out to investigate the dynamic characteristics of cam–follower mechanism. Finally, an optimization cycle, also known as iterative process, is proposed to implement the procedure of single objective optimization and dynamic simulation alternately to improve the kinematic and dynamic characteristics of cam–follower mechanism fully. The cam profile optimization method presented in this paper provides a new tool for cam designers to avoid the undesirable impact and follower jump.

Dynamic analysis and optimization of cutting mechanism about aluminum electrolytic capacitor casing machine

The dynamic characteristics and optimization of a cutting mechanism about aluminum electrolytic capacitor casing machine were investigated with a lumped mass-spring damper model in this paper. In the lumped mass-spring damper model, compliance of the links and effects of mechanism position on deformable transfer relationship are taken into account. Besides, torsional and bending vibrations of camshaft are also considered. Cam profile is an important input excitation of the cutting mechanism and has important influence on the dynamic performance. Therefore, optimization of cam profile was also studied based on the dynamic model and B-spline. Acceleration fluctuations were significantly reduced after the optimization.

Cam profile optimization for a new cam drive

A complex cam shape optimization problem is studied to optimize a unique cam mechanism for a new cam drive engine. First, the optimization problem is defined through analyzing the unique cam mechanism. Multiple design specifications are included in the optimization problem by defining the output torque of the engine as the objective function and the contact stress, radius of curvature, and pressure angle as the constraints. Second, an analytical scenario is designed to find the best ever cam profiles through manipulating the different combinations of cam profile representations and optimization methods. Two types of curve representations, including general polynomial spline and B-spline, are employed in cam profile synthesis. In addition, both a classical optimization technique and a genetic algorithm (GA) based method are applied to solve the complex optimization problem. Finally, comparative studies are performed among the initial profile and the optimal profiles to demonstrate the effectiveness of these proposed design approaches on solving the cam profile optimization problem. Results show that the best profiles are obtained from a combination of the B-spline representation and the GA-based method. In addition, compared to the initial design, the engine performance is improved greatly by the proposed optimization approaches.

The Optimization of Cam Profile - The Development of NEWCAM and MULTICAM Profile

The Optimization of Cam Profile - The Development of NEWCAM and MULTICAM Profile