Function Driven Redesign Method for Conceptual Design

2009 ◽  
Vol 628-629 ◽  
pp. 119-124
Author(s):  
Xu Ling Chen ◽  
Pei Huang Lou ◽  
Dun Bing Tang

In order to assimilate and redesign the existing product, a conceptual design driven by function is proposed. Firstly, the behaviors, structures and functions of the product are analyzed in detail. Then bond graph models are used to describe the behaviors which indicate the dynamic performances of the existing product. Secondly, the advantages and disadvantages of the product can be revealed through these dynamic performances which are abstracted by simulating the bond graph models. To catch the intention of the original design, the simulation results are analyzed regarding the system dynamic performances. According to the evolutional routes, several redesign results are obtained by grouping some optimized alternatives. Finally, applying the method to a frictional driver redesign, the control and dynamic performances are both improved, which verifies the validity and practicability of the proposed design method.

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 854
Author(s):  
Raquel S. Rodríguez ◽  
Gilberto Gonzalez Avalos ◽  
Noe Barrera Gallegos ◽  
Gerardo Ayala-Jaimes ◽  
Aaron Padilla Garcia

An alternative method to analyze a class of nonlinear systems in a bond graph approach is proposed. It is well known that the analysis and synthesis of nonlinear systems is not a simple task. Hence, a first step can be to linearize this nonlinear system on an operation point. A methodology to obtain linearization for consecutive points along a trajectory in the physical domain is proposed. This type of linearization determines a group of linearized systems, which is an approximation close enough to original nonlinear dynamic and in this paper is called dynamic linearization. Dynamic linearization through a lemma and a procedure is established. Therefore, linearized bond graph models can be considered symmetric with respect to nonlinear system models. The proposed methodology is applied to a DC motor as a case study. In order to show the effectiveness of the dynamic linearization, simulation results are shown.


2019 ◽  
Vol 287 ◽  
pp. 01008
Author(s):  
Hrayr Darbinyan

A novel approach of task based conceptual design(TBCD) has been successfully used as direct guider and efficient developer of unique mechanical structures for many cases of mechanical design. Nearly a decade long efforts of elaboration of efficient every day usage formats for this method have been ended in convenient design pages suitable and applicable for revealing, describing, visualizing and managing the data necessary for organizing the design process from task definition to solutions satisfying original design tasks. The aim of current study is to show steps of a solution generation within frames of a single design cycle and extend this action over consecutive design cycles. Those steps are described from standpoint of general concept design method starting from key model and finished with final aggregation matrice as ultimate step of a single design cycle. Unified mathematical expressions are used for introduction and description of all worked out and developed components of conceptual design. The paper is arranged in a way to show gradual steps of conceptual design(CD) of a power transmission system – a pipe wrench life test machine.


1985 ◽  
Vol 107 (3) ◽  
pp. 169-175 ◽  
Author(s):  
D. L. Margolis ◽  
W. C. Yang

Modal bond graph representations of the dissipative model of rigid, cylindrical fluid transmission lines with laminar flow are developed. Modal approximation techniques are used for both hydraulic and pneumatic lines. The modeling and simulation procedures for fluid networks coupled with nonlinear and dynamic systems are greatly facilitated using bond graphs. The physical interpretation of the model is preserved in this approach. Simulation results for hydraulic single lines are compared with results derived by the quasi-method of characteristics. The simulation results for fluid networds for various line and termination configurations are illustrated.


Aerospace ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. 54
Author(s):  
Julia A. Cole ◽  
Lauren Rajauski ◽  
Andrew Loughran ◽  
Alexander Karpowicz ◽  
Stefanie Salinger

There is currently interest in the design of small electric vertical take-off and landing aircraft to alleviate ground traffic and congestion in major urban areas. To support progress in this area, a conceptual design method for single-main-rotor and lift-augmented compound electric helicopters has been developed. The design method was used to investigate the feasible design space for electric helicopters based on varying mission profiles and technology assumptions. Within the feasible design space, it was found that a crossover boundary exists as a function of cruise distance and hover time where the most efficient configuration changes from a single-main-rotor helicopter to a lift-augmented compound helicopter. In general, for longer cruise distances and shorter hover times, the lift-augmented compound helicopter is the more efficient configuration. An additional study was conducted to investigate the potential benefits of decoupling the main rotor from the tail rotor. This study showed that decoupling the main rotor and tail rotor has the potential to reduce the total mission energy required in all cases, allowing for increases in mission distances and hover times on the order of 5% for a given battery size.


Actuators ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 133
Author(s):  
Tobias Vonderbank ◽  
Katharina Schmitz

Increasing performance in modern hydraulics is achieved by a close investigation of possible enhancements of its components. Prior research has pointed out that electromechanical actuators can form suitable alternatives to hydraulically piloted control systems. Since the requirements at these actuation systems depend on the operating conditions of the system, each actuator can be optimized to the respective hydraulic system. Considering that many different conceptual designs are suitable, the phase of conceptual design plays a decisive role during the design process. Therefore, this paper focuses on the process of developing new conceptual designs for electromechanical valve actuation systems using the method of function structures. Aiming to identify special design features, which need to be considered during the design process of electromechanical actuation systems, an exemplary actuator was designed based on the derived function structure. To highlight the potential of function structures for the development of new electromechanical valve actuation systems, two principal concepts, which allow the reduction of the necessary forces, have been developed by extending the function structure. These concepts have been experimentally investigated to identify their advantages and disadvantages.


2013 ◽  
Vol 846-847 ◽  
pp. 313-316 ◽  
Author(s):  
Xiao Yun Zhang

This paper presented a new method based on the Fuzzy self - adaptive PID for BLDCM. This method overcomes some defects of the traditional PID control. Such as lower control precision and worse anti - jamming performance. It dynamic model of BLDCM was built, and then design method for TS fuzzy PID model is given, At last, it compared simulation results of PID control method with TS Fuzzy PID control method. The results show that the TS Fuzzy PID control method has more excellent dynamic antistatic performances, as well as anti-jamming performance. The experiment shows that TS fuzzy PID control has the stronger adaptability robustness and transplant.


2011 ◽  
Vol 48-49 ◽  
pp. 17-20
Author(s):  
Chun Li Xie ◽  
Tao Zhang ◽  
Dan Dan Zhao ◽  
Cheng Shao

A design method of LS-SVM based stable adaptive controller is proposed for a class of nonlinear continuous systems with unknown nonlinear function in this paper. Due to the fact that the control law is derived based on the Lyapunov stability theory, the scheme can not only solve the tracking problem of this class of nonlinear systems, but also it can guarantee the asymptotic stability of the closed systems, which is superior to many LS-SVM based control schemes. The effectiveness of the proposed scheme is demonstrated by simulation results.


1974 ◽  
Vol 41 (2) ◽  
pp. 366-370 ◽  
Author(s):  
N. T. Tsai ◽  
S. M. Wang

The dynamic responses of geared torsional systems are analyzed with the delay-bond graph technique. By transforming the power variables into torsional wave variables, the torsional elements are modeled as transmission line elements. The nonlinear elements, e.g., varying tooth stiffness, gear-tooth backlash, and nonlinear damping, are incorporated into the ideal transmission line element. A computational algorithm is established where the state variables of the system are expressed in terms of wave scattering variables and the dynamic responses are then obtained in both time and space domains. The simulation results of several simple examples of linear and nonlinear geared torsional systems are presented to demonstrate the feasibility of this algorithm.


Author(s):  
Lei Fu ◽  
Yan Shi ◽  
Qinghua Deng ◽  
Huaizhi Li ◽  
Zhenping Feng

The aerodynamic performance, structural strength and wheel weight are three important factors in the design process of the radial turbine. This paper presents an investigation on these aspects and develops an optimization design approach for radial turbine with consideration of the three factors. The aerodynamic design for the turbine wheel with inlet diameter of 230mm for 100kW-class microturbine unit is carried out firstly as the original design. Then, the cylinder parabolic geometrical design method is applied to the wheel modeling and structural design, but the maximum stress predicted by Finite Element Analysis greatly exceeds the yield limit of material. Furthermore, the wheel weight is above 7.2kg thus bringing some critical difficulties for bearing design and turbine operation. Therefore, an integrated optimization design method for radial turbine is studied and developed in this paper with focus on the wheel design. Meridional profiles and shape lines of turbine wheel are optimized with consideration of the whole wheel weight. Main structural modeling parameters are reselected to reduce the wheel weight. Trade-off between aerodynamic performance and strength performance is highly emphasized during the optimization design. The results show that the optimized turbine wheel gets high aerodynamic performance and acceptable stress distribution with the weight less than 3.8kg.


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