• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.3
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• pp.16-22
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• 2005

It is difficult to separate those of NC controller from the error of machine tools because the conventional testing methods to inspect the performance are including the errors of moving system, therefore it has been used as the methods that compare the other controllers. Also, it is hard to predict the machine itself errors with the methods assembling the NC controller and moving system on machine because of the variable load conditions. In this study, the performance inspecting system was developed by analyse the $axis\_rotating$ properties of servo system finally outputting from NC controller. The axis torque was controlled by motor dynamometer and the rotating position accuracy was measured by this developed system.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.2
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• pp.87-96
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• 1995

The cutting force is the most important variable to understand the mechanics of ultra-precision machining. Most dynamometers, however, monitor the static cutting force only. But it is necessary to measure the dynamic cutting force to clarify the machinability of the material, the formation of the chip, chatter and the wear of the tool. In this research, measurement of the dynamic cutting force in order to clarify the machin-ability of the material, the formation of the chip, chatter and the wear of the tool has been conducted. A combined-type dynamometer which could measure the static cutting force and the dynamic cutting force by use of strain gauges and a piezo-film accelerometer has been developed. An analysis of the dynamometer also has been carried out.

• Journal of Mechanical Science and Technology
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• v.15 no.9
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• pp.1248-1256
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• 2001

In this study, a test bed for vehicle longitudinal control is developed using a chassis dynamometer and real time 3-D graphics. The proposed test bed system consists of a chassis dynamometer on which test vehicle can run longitudinally, a video system that shows virtual driver view, and computers that control the test vehicle and realize the real time 3-D graphics. The purpose of the proposed system is to test vehicle longitudinal control and warning algorithms such as Adaptive Cruise Control(ACC), stop and go systems, and collision warning systems. For acceleration and deceleration situations which only need throttle movements, a vehicle longitudinal spacing control algorithm has been tested on the test bed. The spacing control algorithm has been designed based on sliding mode control and road grade estimation scheme which utilizes the vehicle engine torque map and gear shift information.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.45-50
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• 2000

While braking cars, a large amount of energy is taken into the brake system in a short period of time. This leads to some problems ; cracking of the disc, non-uniform wear of pad and disc, fade. Thus it is important to measure the contact thermal behaviour precisely between disc and pad. The measurements must be considered to design the brake system. The paper describes methods to analysis the problem of the thermal behavior on the ventilated disc with ANSYS-a program of FEA and a brake dynamometer. According to this way, the paper can present the error between the data by the dynamometer and the results of analysis by ANSYS.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.211-219
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• 2003

The main study experiments to obtain engine torque of the vehicle during performance test of the recent automobile. Torque was measured through the engine dynamometer to produces engine torque of the vehicle but the research method calculated engine torque of the vehicle without the engine dynamometer. The performance of the vehicle receive various running resistance. The study certificates performance of certification before a certification of used vehicle didn't carry out and certificate. This way evaluated on road test and chassis dynamometer The result of the study shows that it is much possible to apply the test. After comparing the engine torque of road driving with that of chassis dynamometer, the results are approximately the same. When rapidly speeded up, the road-load vehicle can pitch in some degrees, which may result in the fluctuations of acceleration, and then affect on the engine torque. Therefore it is confirmed that this method is easier way to measure the performance of vehicles.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.557-558
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• 2008

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.243-247
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• 2004

The dynamometers which had made in a long time ago could not control the input/output quantity of water minutely and was sensitive to a noise since it was controlled by an analog control method. Therefore, a fully digital controlled system was urgently required to be robust against various noises. In this paper, the new system which can control the amount of circulated water in dynamometer was developed. This system is consisted of an industrial digital type controller and a servo motor. The industrial PLC was used as a main controller for the developed system, and the actuator and servo motor were used to control the inlet and outlet valve independently. The torque signal of load cell was fed back to the main controller to regulate the diesel engines load. Generally, an input/output valve position of the old dynamometer was fixed with a proper situation for an engine output test and the torque was changed according to the time interval. However, the torque value for the dynamometer could not be constantly kept because of the variation of the input water flow and fluid characteristic. Therefore, the automatic control of an inlet and outlet valve should be performed to keep the constant torque. So, the PID control method was applied to solve this problem. Also, the development of a web-based remote control system was described in this paper. This software will give us the convenience of operation, the more efficient operations, and the reduced operator workload for operation of the dynamometer. The application results of the system have been verified at actual diesel engine field.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.11
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• pp.981-988
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• 2016

Dynamometer is a device for testing the performance of the brake and it is composed of a test zone, the mechanical inertia zone, the electric motor and the control zone. Hybrid dynamometer is a way to compensate for the loss of mechanical inertia in accordance with the brake operation by using an electric motor to reduce the size of the mechanical inertia with the advantage that can be tested in the relatively small size of the mechanical inertia and low cost. In this paper, design the proper size of hybrid dynamometer in the laboratory level with the space constraints, analysed the effect of critical parameter on the braking performance of hybrid dynamometer such as changing the friction coefficient. With this study, could get the results of guideline to judge the poor friction material by measuring the torque of the electric motor to compensate the energy loss due to a reduced mechanical inertia.

• Journal of the Korean Institute of Gas
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• v.23 no.2
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• pp.68-73
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• 2019

We proposed a method to convert the CO2 emission data of vehicles collected from the chassis dynamometer test from distance unit to energy unit which generally measured from the engine dynamometer tests. In the future, if engine dynamometer tests are limited, it is expected to be applied as an alternative method to calculate CO2 emission based on energy unit through the chassis dynamometer test. At this moment, engine efficiency is required and the test mode average efficiency should be used to improve the accuracy, not the result derived from specific speed and load conditions. Also, this method was applied to foreign data and the results were within 0.2%. However, CO, NOx and THC which have very low emission characteristics except CO2, are limited by the method proposed in this study and need to be considered separatively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.56-65
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• 2019

Recently, automobiles have been developed for safety and environmental reasons. Particularly, awareness of automobile safety is changing significantly. As a result, safety systems developed by ADAS have emerged. However, the period of mass production through ADAS development and test evaluation is long. Therefore, in this paper, we develop a brake dynamometer to shorten the time required for ADAS development and test evaluation. In addition, the developed brake dynamometer satisfies the international standard JIS D-0210, and the user can evaluate the braking force by selecting test conditions and test method for each mode of ADAS. We use the ACC, LKAS, and AEB scenarios proposed in previous studies to verify the reliability of the developed brake dynamometer. The developed brake dynamometer was verified by comparing the test values and the calculated values using theoretical formulas of the proposed ADAS mode based on previous studies. In addition, it is expected that the performance evaluation of brake parts for each ADAS mode will be possible in an environment where the vehicle test of ADAS is not possible in the future.