• Journal of the Korean Society for Precision Engineering
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• v.24 no.10
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• pp.46-53
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• 2007

This paper describes the development of a high-precision measuring device with DSP (digital signal processor) for the accurate measurement of the 6-axis force/moment sensor mounted to a humanoid robot's ankle. In order to walk on uneven terrain safely, the foot should perceive the applied forces Fx, Fy, and Fz and moments Mx, My, and Mz to itself, and control the foot using the measured them. The applied forces and moments should be measured from two 6-axis force/moment sensors mounted to the feet, and the sensor is composed of Fx sensor, Fy sensor, Fz sensor, Mx sensor, My sensor and Mz sensor in a body (single block). In order to acquire output values from twelve sensors (two 6-axis force/moment sensor) accurately, the measuring device should get the function of high speed, and should be small in size. The commercialized measuring devices have the function of high speed, unfortunately, they are large in size and heavy in weight. In this paper, the high-precision measuring device for acquiring the output values from two 6-axis force/moment sensors was developed. It is composed of a DSP (150 MHz), a RAM (random access memory), amplifiers, capacities, resisters and so on. And the characteristic test was carried out.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.171-175
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• 2011

In this paper, I have developed a high-speed and high-resolution measuring device in order to check the performance of drycell. The system is developed for the drycell manufacturing plant. Measuring time is one of key factors to inference on the production speed. So the developed system is designed to generate the classified result up to 1200ea/min. In the other words, each product can be classified within 25ms. There have been many studies to estimate both state of charge as well as state of health, such as OCV (Open Circuit Voltage), SC (Short Circuit) and measuring impedance with frequency pulse. But those methods take a few second due to surface discharge. To overcome the phenomenon, I developed the method to engage the reverse current to two electrodes of battery. As a result, I could achieve to measure the indigenous capacity without the problem of surface discharge.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.5
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• pp.484-489
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• 2011

Some patients can't use their hands because of inherent and acquired paralysis of their fingers. Their fingers can recover with rehabilitative training, and the extent of rehabilitation can be judged by grasping a cylindrical-object with their fingers. At present, the cylindrical-object used in hospitals is only a cylinder which cannot measure grasping force of the fingers. Therefore, doctors must judge the extent of rehabilitation by watching patients' fingers as they grasp the cylinder. A cylindrical-type finger force measuring system which can measure the grasping force of patients' fingers should be developed. This paper looks at the development of a cylindrical-type finger force measuring system with two-axis force/moment sensor which can measure grasping force. The two-axis force/moment sensor was designed and fabricated, and the high-speed force measuring device was designed and manufactured by using DSP (digital signal processing). Also, cylindrical-type finger force measuring system was developed using the developed two-axis force/moment sensor and the high-speed force measuring device, and the grasping force tests of men were performed using the developed system. The tests confirm that the average finger forces of right and left hands for men were about 186N and 172N respectively.

• Journal of IKEEE
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• v.18 no.4
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• pp.544-551
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• 2014

This paper suggests an algorithm to measure low-level radiation by radiation measuring devices, and the other algorithm to improve reaction speed of the device to better respond to dramatic changes in radiation amount. The former algorithm to improve the accuracy of measuring low-level radiation takes advantage of a dual window radiation measurement method which is based on accumulated average of pulses gathered by a radiation measuring sensor. The latter algorithm is to enhance reaction speed of a measuring device to more sensitively react to dramatic changes in radiation amount by adopting a dual window radiation measurement method which analyzes data patterns newly put into for six seconds. To verify the suggested algorithms, a hardware-which consists of sensor and high-voltage generator, controller, charger and power supply circuit, wireless communication part, and display part-was used. Tests conducted on the dual window radiation measurement method as used in the suggested algorithm have proved that accuracy improves to measure low-level radiation of 5uSv/h, and linearity also gets better. Other tests were conducted to see whether the suggested algorithm enhances the reaction speed of a radiation measuring device so that the device responds better to dramatically changing radiation amount. The experimental results have shown meaningful changes in numbers after six seconds. Therefore, the conclusions are made that the algorithm enhances the reaction speed of the device.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1093-1098
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• 2013

A single-crystal sapphire is used as a transparent bulletproof window material; however, few studies have investigated the dynamic behavior and fracture properties under high-speed impact. High-speed and high-resolution sequential images are required to study the interaction of the bullet with the brittle ceramic materials. In this study, a device is developed to capture the sequence of high-speed impact/penetration phenomena. This system consists of a speed measurement device, a microprocessor-based camera controller, and multiple CCD cameras. By using a linear array sensor, the speed-measuring device can measure a small (diameter: up to 1 2 mm) and fast (speed: up to Mach 3) bullet. Once a bullet is launched, it passes through the speed measurement device where its time and speed is recorded, and then, the camera controller computes the exact time of arrival to the target during flight. Then, it sends the trigger signal to the cameras and flashes with a specific delay to capture the impact images sequentially. It is almost impossible to capture high-speed images without the estimation of the time of arrival. We were able to capture high-speed images using the new system with precise accuracy.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.4
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• pp.97-103
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• 2001

The study on the high-speed machine tool is very important for the improvement of productivity since it can shortens cutting and non-cutting time. Especially, high speed of feed drive system is the major research field. In the industries of the advanced countries, the feed drive systems at the speed of 60 m/min have been already developed based on the high lead ball screws. In this study, a high speed feed drive system at the speed of 60 m/ min has been developed, and its movements characteris-tics are investigated. As the movement characteristics, positioning accuracy, angular accuracy, straightness and micro step-response are measured. Thermal characteristics of the system is also discussed. For measuring the movement characteris-tics, a laser interferometer, a memory-based Hi-coder and a cooling device are used. The experimental results confirm that the movement characteristics and the thermal behavior of the system are satisfactory in the aspect of accuracy and stability.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1548-1556
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• 2006

Appropriate contact force is required for the pantograph on the high speed train to collect current from the catenery system without separation. However, at high speed, large aerodynamic lifting force is generated by the contact plate and the body of pantograph, which may cause wear of the contact wire. In this study, to confirm the interface performance of the pantograph on Korea High Speed Train, a method to measure the contact force of the pantograph was proposed and the related measuring system was developed. The forces acting on the pantograph were clarified and a practical procedure to estimate the forces was proposed. A special device was invented and applied to measure the aerodynamic lifting force. Measured contact forces were displayed by the developed system and evaluated based on the criteria.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.3
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• pp.32-38
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• 2004

Recently, the system of high speed milling(HSM) is widely used for reducing the operation time and maximizing efficiency of work. The most research of high speed milling system is still leaves much to be desired. Specially the research of mass pocket high speed processing with high precision is the first and probably the last. So this paper showed mass pocket processing of high precision with a duralumin and then confirmed a cause of inferior goods through the CAD/CAM pattern simulation and experimentation. And this paper showed high speed processing system reduce the rate of inferior from this optimal pattern.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.11
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• pp.62-69
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• 2009

This paper describes the development of the new type equilibrium sensation measuring system for human with handicap in the equilibrium sensation. The medium and small hospital could not use the developed equilibrium sensation measuring system, because it is very high prices. Therefore, the new type system should be developed to measure the numerical value of the equilibrium sensation in human with handicap. In this paper, First, two 3-axis force/moment sensors which can measure force Fz, moments Mx and My simultaneous were designed and manufactured, second, the high speed measuring device which can acquire the output from two 3-axis force/moment sensors, third, the new type equilibrium sensation measuring system was developed, then the characteristic test of the developed equilibrium sensation measuring system carried out, it is confirmed that the system could measure the swing body of human with handicap.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.604-608
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• 2004

In this paper, an efficient method is proposed to analyze the radial error of a miniaturized-high speed spindle system. Initially, a device is constructed for measuring the radial error motion using capacitance sensors. The capacitance sensors are placed perpendicular to the axis of the shaft and at 90o to each other. The spindle is rotated at high speed and the profile of the spindle is recorded. An algorithm is developed for analyzing the spindle data and determining the radial error of spindle. The present algorithm uses homogeneous transform matrix (HTM) method and iterative process for determining the radial error. The analysis procedure is performed for different speeds of the spindle. The data obtained from the present system and the results of evaluation are also presented in this paper. It is observed that this method is effective in determining and analyzing the spindle errors for high speed miniaturized spindle.