• Journal of the Korean Institute of Gas
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• v.26 no.2
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• pp.9-13
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• 2022

Electric wheelchairs, the output from the motor is mainly applied to a speed reducer using a power transmission device such as a belt or a chain. However, although a speed reducer using a belt or chain is a simple device, it occupies a lot of space and has a space limitation, so it is not suitable for an electric wheelchair driving part. However, since the speed reducer of the planetary gear type is decelerated on the same axis, the volume can be reduced, so the space constraint is less than that of the belt or chain type reducer. Therefore, in this study, a driving part that can obtain great propulsion with a speed reducer using a planetary gear type was developed through a study on the driving part of a wheelchair that can be switched between manual and electric. Accordingly, the tooth shape of the planetary gear applied to the reducer was designed using the Kisssoft program. In addition, the drive part was designed to be applicable to the existing wheelchair wheels, and the mechanism was optimized for the manual/electric switching principle and operation principle of the drive part. Based on the research contents, the final design and manufacture of the wheelchair reducer drive unit in the form of a planetary gear having one sun gear, two planetary gears and one ring gear was carried out.

• Journal of Auto-vehicle Safety Association
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• v.13 no.1
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• pp.45-50
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• 2021

This study aimed to verify the criteria of the driver monitoring systems proposed by UNECE ACSF informal working group and the ministry of land, infrastructure, and transport of South Korea using driving behavior data. In order to verify the criteria, we investigated the safety regulations of driver monitoring systems in a conditional autonomous vehicle and found that the driver monitoring measures were related to eye blinks times, head movements, and eye closed duration. Thus, we took two different experimental data including real-world driving and simulator-based drowsy driving behaviors in previous studies. The real-world driving data were used for analyzing blink times and head movement intervals, and the drowsiness data were used for eye closed duration. In the drowsy driving study, 10 drivers drove approximately 37 km of a monotonous highway (about 22 min) twice. The results suggested that the appropriate duration of eyes continuously closed was 4 seconds. The results from real-world driving data were presented in the other paper - part 1.

• Journal of Auto-vehicle Safety Association
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• v.13 no.1
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• pp.38-44
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• 2021

This study aimed to verify the criteria of the driver monitoring systems proposed by UNECE ACSF informal working group and the ministry of land, infrastructure, and transport of South Korea using driving behavior data. In order to verify the criteria, we investigated the safety regulations of driver monitoring systems in a conditional autonomous vehicle and found that the driver monitoring measures were related to eye blinks times, head movements, and eye closed duration. Thus, we took two different experimental data including real-world driving and simulator-based drowsy driving behaviors in previous studies. The real-world driving data were used for analyzing blink times and head movement intervals, and the drowsiness data were used for eye closed duration. In the real-world driving study, 52 drivers drove approximately 11.0 km of rural road (about 20 min), 7.9 km of urban road (about 25 min), and 20.8 km of highway (about 20 min). The results suggested that the appropriate number of blinks during the last 60 seconds was 4 times, and the head movement interval was 35 seconds. The results from drowsy driving data will be presented in another paper - part 2.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.167.3-167
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• 2001

In this paper, a single degree-of freedom gimbal-structured micro gyroscope and signal processing part including capacitive sensing circuits and filters are designed, fabricated and experimented. We use capacitive sensing method with excitation signal, i.e. sensing excitation signal, to measure the displacement of the moving plate. So, Sensing Output Signal is modulated twice by the excitation signal and driving signal, which is profitable to decouple the driving and sensing mode, to reduce the effect of the acceleration, and to curtail the noises due to parasitic capacitance and driving signal. To reduce driving noises and to improve linearity, the excitation signals and driving signals are modified. Through frequency response analyses ...

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.154-155
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• 2007

This paper describes frequency response of two-mass system for gyroscope applications. The two-mass system of the proposed device is adapted to the sensing part of the gyroscope in this research. Two-mass system has two resonant peaks and wide flat region between two resonant peaks. The resonant frequency of driving part is in this flat region. Therefore, frequency tuning is not necessary for mode matching. In the proposed device, resonant frequency is designed as 7183 Hz in driving part. Mass ratio of two masses in sensing part is 0.1 and device size is 6 mm $\times$ 6 mm. The device is fabricated by SiOG process. The fabricated spring width is increased from $4{\mu}m$ to $4.5{\sim}4.7{\mu}m$, and the measured resonant frequency is 8392 Hz in driving mode. We operated the sensing part using parallel plate of proof mass to verify the sensing part. It is confirmed the device has a wide fiat region in frequency response curve and the resonant frequency of the driving part is in the wide flat region of sensing mode.

• Science of Emotion and Sensibility
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• v.4 no.1
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• pp.53-60
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• 2001

As a part of HMS(Human-Machine System), the car is very important thing in common life. It is also a significant part to study on the controllers of car that is intentively related with all sensibilities during driving. There are lots of controllers on seating buck of the car. However, there are few study on the sensibility analysis of them. Most of all, the foot controller could be easily overlooked because it could be invisible. This study was based on relationship that the controllers fitted to the driving posture in the drivers' sensibility difference of two transmission modes, automatic and manual transmission. The results show the driver's preference driving posture and sensibility in two kinds of transmission cars. Consequently, it should be designed the seating buck for two different types respectively to be taken comfort driving posture and improve the safety for drivers. Also, it could reduce the fatigue and discomfort in the task of driving. The design of the controllers strongly effects on the drivers' response time. hereby this study was accessed to the sensibility of Korean with analyzing the relationship, quantitative data, and sensibility difference between two kinds of transmission cars.

• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.79-88
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• 2011

The purpose of this study was to analyze power requirement of an agricultural tractor by major field operations. First a survey was conducted to obtain annual usage ratio of agricultural tractor by field operation. Plowing, rotary tillage, and loader operations were selected as major field operations of agricultural tractor. Second, a power measurement system was constructed with strain-gauge sensors to measure torque of four driving axles and a PTO axle, speed sensors to measure rotational speed of the driving axles and an engine shaft, pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to calculate power requirement. Third, the major field operations were experimented under fields with different soil conditions following planned operation paths. Power requirement was analyzed during the total operation period consisted of actual operation period (plowing, rotary tillage, and loader operations) and period before and after the actual operation (3-point hitch operating, forward and reverse driving, braking, and steering). Power requirement of tractor major components such as driving axle part, PTO part, main hydraulic part, and auxiliary hydraulic part were measured and calculated to determine usage ratio of agricultural tractor power. Results of averaged power requirement for actual field operation and total operation were 23.1 and 17.5 kW, 24.6 and 19.1 kW, and 14.9 and 8.9 kW, respectively, for plowing, rotary tillage, and loader operations. The results showed that rotary tillage required the greatest power among the operations. Averaged power requirement of driving axles, PTO axle, main hydraulic part, and auxiliary part during the actual field operation were 8.1, 7.8, 3.4, and 1.5 kW, respectively, and the total requirement power was about 70 % (20.8 kW) of the rated power. Averaged power requirement of driving axles, PTO axle, main hydraulic, and auxiliary hydraulic for the total operation period were 6.5, 6.0, 2.1, 0.9 kW, respectively, and total requirement power was about 52 % (15.5 kW) of the rated power. Driving axles required the greatest amount of power among the components.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.3
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• pp.82-89
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• 2002

The need of ultra-precision machine tools, which manufacture and machine the high precision parts used in computers, semi-conductors and other precision machines, has been increased over years. Therefore it is important to design the driving parts, which affect significantly on their performances. In this paper, the dynamic analyses on the belt-driven system were explored. Relation of the acoustical natural frequency and the tension of belt was derived and presented through experiments. Also, while the dynamic loads on motor system were changed, dynamic deflections were calculated through finite element analysis. Nonlinear characteristics of the bearings having an effect on the dynamic performance were studied and the belt connecting the motor (driving part) to spindle of a machine tool (driven part) was modeled as truss and beam elements fur simulations under various conditions, and a beam element model was verified to be more useful.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.928-931
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• 1996

It is necessary to develop the simulator for the test of stability and torque before the walking experiment of biped robot, because a robot may be damaged in an actual experiment. This thesis deals with the development of three-dimensional simulator for improving efficiency and safety during development and experimentation. The simulator is composed of three parts-solving dynamics, rendering pictures and communicating with the robot. In the first part, the D-H parameter and parameter of links can be loaded from the file and edited in the program. The results are obtained by using the Newton-Euler method and are stored in the file. Through the above process, the proper length of link and driving force can be found by using simulator before designing the robot. The second part is organized so that the user can easily see a specific value or a portion he wants by setting viewing parameters interactively. A robot is also shown as a shaded rendering picture in this part. In the last part, the simulator sends each desired angle of joints to the robot controller and each real angle of joints is taken from the controller and passed to the second part. The safety of the experiment is improved by driving the robot after checking whether the robot can be actuatable or not and whether the ZMP is located within the sole of the foot or not for a specific gait. The state of the robot can be easily grasped by showing the shaded rendering picture which displays the position of the ZMP, the driving force and the shape of robot.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.3
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• pp.388-395
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• 2009

Surveillance Radar System for naval vessels is a primary core sensor for command and fire control, and provides CFCS(Command and Fire Control System) information for 3-D surveillance and fire control. It's composed of Antenna, Transmitter/Receiver, Signal Processor, and Air drier, which are installed on and under deck. They should be designed and produced in order to endure at any operating circumstances. This paper analyzes load of a driving part for driving the antenna considering factors under external operating circumstances, and proposes a condition of load for maintaining fixed RPM through analyzing internal load of the driving part, and how to reduce the load to meet the condition. This paper is verified through experimental studies.