• Journal of Industrial Technology
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• v.19
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• pp.15-23
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• 1999

Active damping system is generally used for the vibration suppression and precise motion control for the flexible structure. This application can be easily found on the space structure and driving mechanism of optical storage devices. Although a control system using the flexible structure has many advantages over using rigid mechanism in driving energy saving, system weights, and etc., more complex and precise control strategies are required. A position control system using flexible structure and the concept of active damper is designed and manufactured, which is driven by slide DC motor and moving coil motor located at the tip of the flexible beam. Dynamic characteristics of this system are investigated by analytic and experimental ways. By the comparison of those two results, a nominal reference model for this system is proposed.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.3
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• pp.129-136
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• 2013

In this paper, a motion control system based on 2-axis gimbal system is designed and implemented to drive a high speed and precision. The proposed system consists of the RS-422 interface, 2-axis gimbal platform, servo control unit integrated with a high speed DSP chip-set, servo amplifier unit, potentiometer sensor unit, and resolver sensor unit. The servo control unit using the high speed DSP firmware is designed to get a fast response without an overshoot with step input and a RMS error of low probability with ramp input. The servo amplifier unit using a voltage control is designed to resolve the zero-crossing distortion for precise motion. To verify the performance and stability of the implemented system, experiments are performed through a measurement of the time and frequency domain response in a laboratory environment by using a PXI(PCI eXtentions for Instrumentation).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.8
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• pp.81-87
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• 2020

A stable rotational-to-linear motion transformation structure using a driving mechanism with 2 degrees of freedom was developed for an orthogonal mechanism to prevent the interference of each axis in 2D motion. In this mechanism, a step motor was used for precise position control. This structure was developed to maneuver workparts in micro particle blast machining experiments. To determine the real-time performance of micro particle blast machining, the control, input, and output were operated simultaneously and precise position control was implemented, using a timer interrupt with multiple execution codes. The two step motors obtained precise position control by removing backlash with a ball-screw mechanism. The device has menu-type control codes for user-friendliness, and real-time sequence control was simultaneously adopted for user control input.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.458-461
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• 1995

A new type of rotational motor which is developed has a resolution smaller than 10 $^{-4}$ radian and can be accessed for full rotational angles. The operation principle of the motor is based on inchworm motion of two belt driving mechanism. Flexure hinge mechanism, which is pertinent to symmetry construction of the motor, is designed to minimze the effort to frame and is analyzed by using finite element method. Depending on input signal amplitude, rotational angle by one cycle is varied form 0.2*10 $^{-4}$ rad to 9.76* $^{-4}$ rad. This shows that it has the capability of getting very small rotational angle by considering radius of rotor and amplitude of input signal.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.11
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• pp.64-69
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• 2020

To determine the effective factors for microparticle blasting with precise sequence position control in the x-axis and y-axis directions, we conducted a statistical experimental analysis of blasted square shapes by considering five condition factors. The control input and output were operated simultaneously by rotation-linear motion conversion and fine particles were blasted onto the aluminum specimen by precise position control driving using multiple execution codes. The micro-driving device used for processing was capable of microparticle blasting and of controlling the system through contact with a limit sensor at high speed and a two-degree-of-freedom driving mechanism. Our experiments were conducted on 1,050 specimens of pure aluminum (containing <1% of other elements). The effects of several factors (e.g., particle and nozzle diameters, blasting pressure, and federate and blasting cycle numbers) on the surface roughness and blasted surface's depth were verified through a statistical experimental analysis by applying the dispersion analysis method. This statistical analysis revealed that the nozzle diameter, the blasting pressure, and the blasting cycle number were the dominant factors.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.2
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• pp.49-53
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• 2007

In this study, we investigated experimentally the potential of a planer positioning mechanism with three degrees of freedom using a flexure guide and an electromagnetic linear motor. The goal was to produce a multi-axis positioning system with nanometric resolution over a 1-mm stroke. An $X-Y-\theta$ stage was designed based on previous results from a single-axis prototype and was constructed with a flexure guide mechanism and voice coil motor type linear actuators. We examined the necessity of a driving method and control system to ensure high resolution for multi-axis positioning. Experiments were conducted to evaluate the performance, and the results confirmed the mechanism's potential; fine point-to-point (PTP) positioning was achieved over a 1-mm stroke, with a resolution of 2 nm for translation in X-Y and 0.01 asec for yaw in $\theta$.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.7
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• pp.26-31
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• 1995

A new actuating mechanism suitable for a micro positioning device is developed using piezo-electric elements. The actuator can make a step movement of 0.5 .mu. m up to 3.5 .mu. m. The step size can be adjusted on demand. By repeating this step action, long distance movement is achieved. Precise positioning can be obtained by combining the coarse motion with the maximum step size and fine motion. Two types of fine motion have been proposed for a driving method. Firstly, feedback control bases on PID is applied. The experimental results for the two method are presented.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.25-27
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• 1998

The switched reluctance motor(SRM) drive system provides a good adjustable speed and torque characteristics. However, it also has some drawbacks such as relatively high torque ripple and acoustic noise which are caused by the torque production mechanism. To reduce torque ripple and to have precise speed control, PLL technique is adopted. The PLL system in conjunction with dynamic dwell angle control scheme has good speed regulation characteristics. Digital control system with a 80c196kc micro-controller is used to be realized this drive system. Test results show that the suggested control system has the ability of dynamic and precise speed control.

• Journal of Biosystems Engineering
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• v.36 no.3
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• pp.171-179
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• 2011

Facing the current hikes of labor wage and high oil price, it is needed to have energy-saving machinery which also enables us precise farm operations. Thus, it was necessary to develop a safe machine which allows secure and pleasant works along orchard slopes. In this study, a lifting utility with balance-controlled platform was developed. The platform utility could maintain to level the workbench while driving along slopes. Even the machine body was driven at the tilt angle ranges of ${\pm}20^{\circ}$, the platform bench could be maintained within ${\pm}0.5^{\circ}$ of a gimbal angle. In addition, the machine lifted up to 2.0 m using an electric-hybrid driving mechanism with a low noise. A tandem hybrid power source was developed with a DC 72 V, 100 AH for the Deep-Cycle batteries, charged with 3.5 kW gasoline generator as an auxiliary power source. HST, which is one of the CVT's, was adopted as a transmission device, and a crawer track was used for the safety of the vehicle against tip-over. The maximum lifting height of platform was is 2,500 mm, and the maximum extendable width was 2,900 mm.

• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.41-48
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• 2011

In order to detect driver's state in a driver safety system, both overt and covert measures such as driving performance, visual attention, physiological arousal and traffic situation should be collected and interpreted in the driving context. In this paper, we suggest a vehicle monitoring system that provides multimodal information on a broad set of measures simultaneously collected from multiple domains including driver, vehicle and road environment using an elaborate timer equipped as a soft synchronization mechanism. Using a master timer that records key values from various modules with the same master time of short and precise interval, the monitoring system provides more accurate context awareness through synchronized data at any given time. This paper also discusses the data collected from nine young drivers performing a cognitive secondary task through this system while driving.