• Transactions of the Korean Society of Automotive Engineers
• /
• v.2 no.3
• /
• pp.33-39
• /
• 1994

The purpose of this research is to examine precise linear motion and rotary motion. A six-degrees-of-freedom fine motion mechanism is introduced to drive an object precisely in directions of X, Y and Z-axes and around them : three rectangular linear motion and rotary ones. An experimental mechanism is introduced in which a $70$\times$70$\times$70$\times$(${mm}^3$) cube object is driven by six PZT actuator. The study is to establish the six-degrees-of-freedom fine motion mechanism of linear motion and rotary motion using PZT actuator.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2011.06a
• /
• pp.399-400
• /
• 2011

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.1593-1596
• /
• 1997

Because the leg mechanism of walking roblt affect on the mobility and energy efficiency, we focus on the design of new leg mechanism based on the previous leg mechanisms. We mention the deficiency of the previous leg mechanisms and propose a new leg mechanism that consists of a 2-d.o.f pantograph mechanism and a vertical linear actuator. The pantograph mechanism is attached to the horizontal plane of the body and the verical linear actuator is vertical to that plane. In order to design a quadruped walking robot, we consider the kinematics of the 2-d.o.f pantograph mechanism and the arrangement of twol linear motion guides that drive the pantograph mechanism.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1225-1228
• /
• 2004

Principles and mechanism of energy transduction of dielectric polymer materials are well known from the various smart material related publications. However their introduction to industrial actuator applications is limited mainly due to difficulties guarantee controllability and reliability. Most of the previous publications have elaborates energy transduction physics of chunk of polymer while development of construction methods for feasible actuators made of the material is rarely proposed. In the present article, a conceptual design of multi-DOF linear polymer actuator construction that is to be controllable with moderate level of control work os introduced. In addition, numerical models that are developed with a unified energy based approach are presented not only for basic working mechanism analysis of the polymetric soft actuator but for providing analytical foundation to expend the concept toward design of multi-DOF actuator controls.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.22 no.3_1spc
• /
• pp.587-592
• /
• 2013

Until recently, the primary users of wheelchairs were people with lower body disabilities. However, the number of patients recovering from accidents or surgery, as well as the number of elderly people using wheelchairs, is constantly increasing. This study examined the design and manufacture of standing and gait assist wheelchairs that assist temporary gait disturbed patients to take rehabilitation training and elderly people to engage in walking exercise. A kinematic analysis was used to select a drive motor and design a four-bar linkage mechanism for lifting the backrest vertically. Using a multibody dynamic simulation, detailed design was performed taking into consideration the spatial motion and partial interference, and the necessary push force and stroke of the linear actuator were also calculated. To ensure structural safety, the von-Mises equivalent stresses of the upper and lower brackets of the linear actuator were verified through a finite element analysis. The manufactured wheelchair was shown to operate successfully as intended, using the developed controller for the drive motors and linear actuator.

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.84.4-84
• /
• 2002

$\textbullet$ To achieve 3 high power-to-weight ratio, design of 3DOF hip module $\textbullet$ Using parallel mechanism and linear actuator consist of a ball-screw mechanism $\textbullet$ The kinematics analysis for the hip module $\textbullet$ A kinematic index to measure actuator power are introduced. $\textbullet$ It is demonstrated throught simulation that incorporation of redu ndant actuator into the hip module

• Journal of Drive and Control
• /
• v.9 no.2
• /
• pp.8-14
• /
• 2012

Electro-hydraulic spring return actuator(ESRA) is utilized for air conditioning facilities in a nuclear power plant. It features self-contained, hydraulic power that is integrally coupled to a single acting hydraulic cylinder and provides efficient and precise linear control of valves as well as return of the actuator to the de-energized position upon loss of power. In this paper, the algebraic equations of ESRA at steady-state have been developed for the analysis of static characteristics that includes control pressure and valve displacement of pressure reducing valve, flow force on flapper as well as its displacement over the entire operating range. Also, the effect of external load on piston deviation is investigated in terms of linear system analysis. The results of static characteristics show the unique feature of force balance mechanism and can be applied to the stable self-controlled mechanical system design of ESAR.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.54 no.1
• /
• pp.33-39
• /
• 2005

In this paper, we propose a slider servo-mechanism driven by electro-magnetic actuator to improve straightness of linear motor stages. Based on axial-position dependent deterministic characteristics of the straightness error, a feedforward compensation control is appled to reduce the straightness error. In the consideration of uncertain properties of friction and its effects on positioning accuracy, a sliding mode control is applied. The effectiveness of the suggested mechanism and the control performances are illustrated along with some experimental results.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.10
• /
• pp.92-98
• /
• 2008

This paper is concerned with the designing and making power standing wheelchair. This wheelchair is studied based on the mechanical and electrical engineering concepts and theories. The mechanical theories are composed of statics and dynamics knowledges that are related with moving and standing position. Basically the static and dynamic stability is the most important element in designing and making the real size model. The linear actuator is used in the standing mechanism and the joystick controlled by hand is attached on the arm rest. The real size model is made and also investigated through the design specifications by test drive. Finally, this paper proves the possibility of commerical production of power standing wheelchair.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.530-536
• /
• 2004

In this paper a servo-system is developed to improve straightness of linear motor stages. When a linear motor stage is used for high-precision linear motion systems, high precision straightness accuracy is necessary to meet the required position accuracy. In such cases, machining and assembling cost increases to improve the straightness accuracy. An electro-magnetic actuator which is relatively cost effective than any other conventional servo-systems is suggested to compensate the fixed straightness error. To overcome the compensation error due to the friction, a sliding mode control is applied. The effectiveness of the suggested mechanism and the control performance are illustrated along with some experimental results.