Reliability Improvement of Machine Tool changing Servo Motor

Sung, Baek-Ju,Lee, Jong-Bae The Korean Institute of Electrical Engineers 2011 The Journal of International Council on Electrical Vol.1 No.1

First of all, it is the most important to know the cause and effect of major failures to increase the reliability of servo motor. All reliability parameters can be achieved after analysis of them and experiments based on the analysis data. So, we firstly made out the failure analysis data of servo motor such as FMMA, FMECA, FTA, and 2-stage QFD considering the reference materials, field failure data, and the opinion of experts of servo motor. And the test items were decided which are needed to evaluate the performance characteristics of servo motor as analysis results of failure analysis data. And then, the major reliability parameters are deduced by experiments and MINITAB analysis. In addition, according to prove a major failure mode of servo motor by above analysis results, we produced FEA (Finite Element Analysis) model about shape of stator and rotor of servo motor to find out the reducing method of cogging torque. This paper presents the useful major reliability parameters, detailed failure mode analysis data, experimental results using 3 samples, and a cogging torque reducing method of servo motor, and also verified the validity of the deduced parameters and analysis data.

근전도 신호와 BLDC모터 제어를 통한 무릎재활시스템

권형기,고형규,송윤오,손의성,이붕주 한국전자통신학회 2019 한국전자통신학회 논문지 Vol.14 No.5

This research is the design and implementation of a rehabilitation medical device based on a EMG measurement. Rehabilitation systems are controlled using BLDC motors and motor drives. The BLDC motor drive controls the operation and the speed controls the drive through the external servo motor. The potentionmeter coupled to the outside of the motor transmits information about the position of the load being rotated by the motor. The rehabilitation algorithm executes the periodic contraction relief rehabilitation at a certain angle range by speed stage and controls the maximum angle of 0-120 using the motor according to the user setup stage during the rehabilitation exercise. The walking algorithm compensates motor control for legs with low avionics signal by motor control using differential values of signals obtained by EMG measurement attached to both innermost roots and controls the maximum angle of 0 to 88 using motor and EMG measurement during walking motion. In addition, the application implements a more convenient knee rehabilitation system to confirm the feasibility of the application. 본 연구에서는 표면근전도 측정기 기반의 재활 의료기기의 설계 및 구현에 관한 내용을 기술한다. 재활시스템은 BLDC모터와 모터 드라이브를 이용하여 제어된다. BLDC모터 드라이브는 동작 제어를 하며, 속도는 외부 서보모터를 통해 드라이브를 제어한다. 모터 외부에 결합된 포텐쇼미터는 모터에 의해 회전하는 부하 위치 정보를 전달한다. 재활 알고리즘은 환자가 일정 각도 범위에서 주기적인 수축⋅이완 재활운동을 속도단계별로 실행하며 재활운동 시 사용자 설정 단계에 따른 모터를 활용하여 0∼120[]의 최대각도를 제어한다. 보행 알고리즘은 양쪽 안쪽넓은근에 부착된 표면근전도 측정기로 획득한 신호의 차이 값을 이용하여 근전도 신호가 낮은 다리에 모터제어로 보상해주며 보행운동 시 모터와 표면근전도 측정기를 활용하여 0~88[]의 최대각도를 제어한다. 또한, 어플리케이션으로 보다 편리한 무릎재활시스템을 구현하여 실용화 가능성을 확인하였다.

서보모터 타입 모터다이나모를 이용한 전기이륜차 주행성능 평가를 위한 동적 시뮬레이터 개발

강대경(Daekyung Kang),서상근(Sanggeun Seo),최완규(Wankyou Choi),김홍진(Hongjin Kim),김민수(Minsoo Kim) 한국자동차공학회 2014 한국자동차공학회 부문종합 학술대회 Vol.2014 No.5

We have developed the dynamic simulator to evaluate the drive performance of the electric two-wheelers through the HIL(Hardware in the loop) test on the motor dynamometer with the servo motor. In the HIL test, the servo motor of the dynamometer applies the road load to the motor under test according to the speed and the acceleration of the motor. To check the availability of the developed simulator, we have compared the results of the simulation on the dynamometer with the field tests. In field test, we rode the e-bike with BLDC motor and Li-ion battery and performed the coastdown test in order to find the correlation of the road load and e-bike’s speed. And we carried out the test for the acceleration performance. After the field test, we assigned the correlation of the road load-speed to the dynamic simulator and simulated the e-bike’s drive about the coastdown and the acceleration performance from the standstill. From the comparisons, we concluded our developed simulator was very available for the drive simulation of the e-bike’s drive on the real road.

서보모터 기반 풍동모형 조종면 힌지모멘트 측정

이종건,오세윤,이영빈,김송진 한국항공우주학회 2013 한국항공우주학회 학술발표회 논문집 Vol.2013 No.11

본 논문은 서보모터로 구동되는 풍동모형 조종면의 힌지모멘트를 측정하기 위한 방법을 기술하였다. 풍동모형 조종면의 변위각을 제어하며 힌지 모멘트를 측정하기 위해 서보 모터 제어 시스템을 구성하였다. 조종면의 힌지 모멘트는 서보 모터 구동 전류로부터 구하였다. 힌지모멘트와 서보모터 구동전류간의 선형관계를 확인하였다. This paper describes a method to measure a hinge moment of wind tunnel model control surface driven by servo motor. A servo motor control system was implemented to control the deflection angle of wind tunnel model control surface and to measure the hinge moment. The hinge moment of control surface was obtained with the driving current of the servo motor. The results show a linear relation between the hinge moment and driving current of the servo motor.

듀얼 서보모터 구동형 프레스 시스템의 동기화 제어기법 연구

나상건(Sang-Gun Na),권오신(O-Shin Kwon),강재훈(Jae-Hoon Kang),허훈(Hoon Heo) 한국생산제조학회 2013 한국생산제조학회지 Vol.22 No.2

In this paper, a synchronization control technique of dual-servo motor driven press system is proposed. An independent cascade PID control technique has been applied to the conventional press system for advancement of control stability. However, it is not easy to reduce synchronous error using the independent cascade PID control technique when some different load disturbances are involved in each motor. The eccentric error of the slide caused by the problem degrade the control performance of the BDC(Bottom Dead Center). In order to achieve reduction of the synchronous error between two servo motors and accurate position control simultaneously, a new control scheme comprised with cascade PID control loop and cross-coupling loop is proposed. In simulation using Matlab SIMULINK, the AC servo system is designed. The control performance of proposed technique is compared with conventional control technique to the model of AC servo system. Also, the sub-scale model of dual-servo motor driven press system which can replicate the slide motion is constructed for experimental verification for the performance of the proposed control technique. The cross-coupling control technique reveals more precise and stable performances in the position and synchronization controls.

Analysis of Life Characteristics of Servo Motor for Mobile Robot

Baekju Sung,Jongbae Lee,Dosik Kim,YongBum Lee 한국신뢰성학회 2021 신뢰성응용연구 Vol.21 No.1

Purpose: The servo motor for mobile robots is a key component of the driving parts of industrial robots. Analysis of major failure factors of servo motors and analysis of life characteristics can be used to predict the life of a mobile robot. Methods: A failure analysis of servo motors for mobile robots is prepared through literature and expert opinions, and major failure modes are identified. In addition, the accelerated life test is performed, and the performance degradation of the servo motor is estimated by analyzing the test results. Result: FMECA was created through failure analysis, and major failure modes were identified. Through the analysis of the results of the accelerated life test, the life distribution of the servomotor for the mobile robot was confirmed and its suitability was verified. Conclusion: Life characteristic value of servo motor for driving mobile robot such as Weibull distribution and shape parameters calculated by verifying the suitability of the life distribution of a servomotor for a mobile robot are applied to calculate the warranty life of the servo motor.

Robust Current Control for Permanent Magnet Synchronous Motors by the Inverse LQ Method - An Evaluation of Control Performance Using Servo-Locks at Low Speed -

Takami Hiroshi The Korean Institute of Power Electronics 2004 JOURNAL OF POWER ELECTRONICS Vol.4 No.4

This paper describes the optimal current-control of a permanent magnet synchronous motor by the use of robust and simple current controllers, based upon the analytical procedure known as the inverse LQ (ILQ) design method. The ILQ design method is a strategy for finding the optimal gains based on pole assignment without solving the Riccati equation. It is very important to keep the motor in robust servo-lock. By experiments and simulations, we will show that the ILQ optimal servo-system with servo-lock is more insensitive at low speeds to variations in armature inductance than the standard PI servo-system. Variations in armature inductance have the greatest influence on the responses of a servo-system.

기전 시스템의 구동 모터 선정 방법과 견마로봇용 지뢰탐지 구동 장치에의 적용

최창환,정승호,김석환,이정엽,최덕선,정상철,박용운,Choi, Chang-Hwan,Jung, Seung-Ho,Kim, Seok-Hwan,Lee, Jeong-Yeob,Choe, Tok-Son,Chung, Sang-Chul,Park, Yong-Woon 한국군사과학기술학회 2007 한국군사과학기술학회지 Vol.10 No.4

This paper presents a motor selection technique for a manipulator design that is used in a multipurpose dog-horse robot. Since the dynamics of a manipulator and its servo drives are closely related to each other, it requires a repetitive analysis to determine a suitable motor. In order to simplify this procedure, Straete et al. proposed a simple normalization method to separate the load dependent terms and the motor dependent terms. This technique is adopted in this paper for selecting a motor in designing a manipulator.

서보모터를 이용한 유압 하이브리드식 사출성형기의 공정시간 및 절전효과에 관한 연구

윤홍식,김성동 사단법인 유공압건설기계학회 2020 드라이브·컨트롤 Vol.17 No.3

The cycle time and power saving effect of a hydraulic hybrid injection molding machine using a servo motor are considered in this paper. In order to verify control characteristics, such as pressure and speed, experiments were performed with the hydraulic hybrid injection molding machine, clamping force of 110 ton. The power consumption and production cycle time of a conventional hydraulic injection molding machine were measured to compare its performances with the hydraulic hybrid injection molding machine. An injection molding machine with a clamping force of 1300 ton was used as the conventional machine, the hybrid machine was implemented by replacing its induction motors with servo motors. In the remodeled hybrid machine, experiments were performed to investigate how the displacement of the mold clamping pump affects the power consumption and production cycle time. The results showed that the production cycle time of the hybrid injection molding is similar to a conventional hydraulic injection molding machine but with a significant energy saving of about 40%.

블록코일 고정자를 이용한 슬롯리스 서보모터의 개발

원성홍 대한전기학회 2023 전기학회논문지 P Vol.72 No.4

This paper presents a development process of slotless motors using block-coil stator. The slotless motors have many advantages such as no cogging, high controllability. However, the manufacturing process of slotless motors is known to be very difficult and thus the manufacturing cost is very high. This is an obstacle to the proliferation of slotless motors despite many advantages. However, the block coil stator type slotless motor is emerging as a new alternative to overcome the weakness of the slotless motor, which is difficult to manufacture. So, in this paper, the author present novel manufacturing process of a slotless motor known as block-coil stator and the verification through design and prototyping of block-coil stator slotless motors.