2014 14th International Conference on Control, Automation and Systems (ICCAS 2014) Oct. 22-25, 2014 in KINTEX, Gyeonggi-do, Korea 1. INTRODUCTION Conventional linkages are usually composed of closed-loop single degree of freedom kinematic chains. They can operate at high speed with heavy loads and high output precisions, but they cannot provide any versatility such as quick action motion that is often required in many automated instruments and industrial applications[1]. In recent years, linkage systems are extensively applied in high speed structures and parallel manipulators. The linkage structures especially four-bar linkage systems are frequently used in high speed parallel robot, such as the Japanese Quattro parallel robot or high speed wire-driven robots [2, 3]. In this paper, a cam-based four-bar linkage system is applied to allow for a very high speed and adjustment the motivation in quick-action movement. Cam-follower mechanisms are widely used in many types of modern machines not only because of arbitrarily complicated motions have been achieved by the brief simple-compact cam-based construction [4], but also based on their excellent properties for operation speed, motion accuracy, structural rigidity, and production cost [5, 6]. However, in many cased, machines require cam to provide a quick follower movement or to work at high-operating speed, which always required the special designed cam. For instance, a high speed cam has been calculated for a down-swing paper transferring mechanism in a printing press, a quick-action cam has been diagrammatized to control the switching action for a vacuum circuit breaker, and a floating cam has been improved to satisfy the motion of a jumping robot [7-9] . Traditionally, several smooth profiles, such as trigonometric functions, s-curves, and polynomial profiles are used to produce high speed quick-action cams [6, 10]. However, as the requirements in high-speed conditions, linkage structure and cam-follower system are not the alternative mechanism, multitudinous of techniques are proposed in many aspect to achieve the high speed motions and robots such as electric systems or hydraulic systems. Nonetheless, compare to the cam-based linkage mechanical system, energy-intensive and complicated control would become the big problems of electric system. For hydraulic system, complicated structural, bulky size and high cost would be some non-negligible significant predicament which would weaken the performance in quick action movement [11]. For a linkage mechanism, the motion of high-speed could consist of three patterns, 1) Fast-forward (FF); 2) Fast-reverse (FR); 3) Fast-forward-reverse (FFR) [11]. From this classification, the definition of quick-action motion could be settled affiliate to the high speed motivation but just emphasis on short-time performance. Therefore, these two structures are similar in the analysis of kinematic and dynamic models. In this paper, the contribution of the designed cam is that the cam counter offers a non-constant velocity actuates the four-bar linkage to produce a quick-action motivation. In the following sections, we first introduced the underling calculation of the cam-follower system, outline the designed cam profile, present its velocity and acceleration curves. Then the mechanism design of the cam-based linkage system will be given in section2. Section 3 shows the kinematic model and the calculated equations. Finally, section 4 concludes the paper and offers some perspectives. 2. HIGH-SPEED CAM SYSTEM DESIGN In the classification of cam follower motion, there are two basic curves: dwell-rise-dwell (DRD), rise-return-rise (RRR) [10]. For the application of our system, we compound the follower motion curve as rise-dwell-return-dwell (RDRD). In Fig1, picture (a) shows the displacement curve of cam follower motion and the boundary conditions that will apply in the follow polynomial equations. High-Speed Cam Design for Quick-Action Linkage System Jing Wu 1 , Rui-Jun Yan 1 , Chao Yuan 1 , Yong Seok Lee 2 , Kyoo-Sik Shin 3 , and Chang-Soo Han 3* 1 Department of Mechatronics Engineering, Hanyang University, Republic of Korea (wujing@hanyang.ac.kr; yrj@hanyang.ac.kr; chaoyuan2013@gmail.com ) 2 Department of Mechanical Engineering, Hanyang University, Republic of Korea (pacheon76@hanyang.ac.kr ) 3 Department of Robot Engineering, Hanyang University, Republic of Korea (norwalk87@hanyang.ac.kr; cshan@hanyang.ac.kr * ) * Corresponding author Abstract: As a specially designed mechanism, cam is usually be used in many high-speed structures and mechanisms. Diverse geometric cam counters support for diverse motion applications, including the displacement, the velocity and the acceleration. This paper proposes a design of a high-speed cam which can be applied in a quick-action-based four bar linkage system. This variable high-speed cam is design by using the graphical combination of 5 th and 7 th polynomial cam curves. In addition, the kinematic model of a linkage system based on our proposed cam is constructed. Finally, the simulation results of the cam counter, velocity and acceleration of the designed cam are shown to validate the appropriate application of a quick-action linkage system. Keywords: Polynomial high-speed cam, quick action system, linkage system, kinematic model. 978-89-93215-06-9 95560/14/$15 ⓒICROS 494