중첩 초음파 센서 링의 성능 평가, 최적 설계 및 복합 장애물 탐지

김성복,김현빈,Kim, Sung-Bok,Kim, Hyun-Bin 한국융합신호처리학회 2011 융합신호처리학회 논문지 (JISPS) Vol.12 No.4

This paper presents the performance evaluation. optimal design. and complex obstacle detection of an overlapped ultrasonic sensor ring by introducing a new concept of effective beam width. It is assumed that a set of ultrasonic sensors of the same type are arranged along a circle of nonzero radius at regular spacings with their beams overlapped. First, the global positional uncertainty of an overlapped ultrasonic sensor ring is expressed by the average value of local positional uncertainty over the entire obstacle detection range. The effective beam width of an overlapped ultrasonic sensor ring is assessed as the beam width of a single ultrasonic sensor having the same amount of global positional uncertainty, from which a normalized obstacle detection performance index is defined. Second. using the defined index, the design parameters of an overlapped ultrasonic sensor ring are optimized for minimal positional uncertainty in obstacle detection. For a given number of ultrasonic sensors, the optimal radius of an overlapped ultrasonic sensor ring is determined, and for a given radius of an overlapped ultrasonic sensor ring, the optimal number of ultrasonic sensors is determined. Third, the decision rules of positional uncertainty zone for multiple obstacle detection are provided based on the inequality relationships among obstacle distances by three adjacent ultrasonic sensors. Using the provided rules, the obstacle outline detection is performed in a rather complex environment consisting of several obstacles of different shapes. 본 논문에서는 유효 빔 폭 개념을 새로이 도입하여 중첩 초음파 센서 링의 성능 평가, 최적 설계, 그리고 복합 장애물 탐지에 대해 기술하도록 한다. 일군의 동종 저지향성 초음파 센서들이 반경이 영이 아닌 원주 상에 일정 간격으로 상호 빔 폭이 중첩되도록 배치된다고 가정한다. 첫째, 중첩 초음파 센서 링의 전역 위치 불확실성을 전체 장애물 탐지 범위 내에서의 국부적 위치 불확실성의 평균값으로 나타낸다. 중첩 초음파 센서 링의 유효 빔 폭을 동일한 전역 위치 불확실성을 갖는 단일 초음파 센서의 빔 폭으로 산정하고 이를 바탕으로 정규화된 장애물 탐지 성능 평가 지수를 정의한다. 둘째, 정의된 성능 평가 지수를 이용하여 장애물 탐지 시 위치 불확실성이 최소화되도록 중첩 초음파 센서 링의 설계 사양을 최적화한다. 주어진 초음파 센서의 사용 개수에 대한 중첩 초음파 센서 링의 최적 반경 그리고 주어진 중첩 초음파 센서 링의 반경에 대한 초음파 센서의 최적 사용 개수를 결정한다. 셋째, 3개의 인접 초음파 센서로부터의 장애물 거리 간의 대소 관계에 의거한 복수 장애물의 위치 불확실성 영역 판정 기준을 제시한다. 제시된 위치 불확실성 영역판정 기준을 이용하여 다양한 형태의 장애물로 구성된 복합 장애물 환경에서의 장애물 윤곽 추출 결과를 보인다.

위치 불확실성 감소를 위한 중첩 초음파 센서 링의 설계

김성복,장재희 제어로봇시스템학회 2009 제어로봇시스템학회 각 지부별 자료집 Vol.2009 No.12

This paper presents the principle of reducing the positional uncertainty inherent to an ultrasonic sensor using overlapped ultrasonic sensors and the effective arrangement of ultrasonic sensors for reduced positional uncertainty. It is assumed that ultrasonic sensors used are of a wider beam width which are avaiable at a lower cost. First, for both single and double obstacles, we explain that the overlapped beam pattern of two adjacent ultrasonic sensors can reduce the positional uncertaint of an individual ultrasonic sensor. With the entire sensing zone of two ultrasonic sensors divided into three smaller sub zones, how to determine the sub zone where the detected obstacle belongs from the measurements of two ultrasonic sensors. Next, aiming at reduced positional uncertainty, we propose a optimal design of an ultrasonic sensor ring in which a set of ultrasonic sensors are arranged at a regular interval with their beams overlapped. As an example, the optimal design of an overlapped ultrasonic sensor ring using commercial ultrasonic sensors having a low directivity is given.

효과적인 빔 폭 중첩을 이용한 고성능 장애물 탐지용 중첩 초음파 센서 링의 최적 설계

김성복,김현빈,Kim, Sung-Bok,Kim, Hyun-Bin 한국융합신호처리학회 2011 융합신호처리학회 논문지 (JISPS) Vol.12 No.1

본 논문에서는 인접 초음파 센서간 효과적인 빔 폭 중첩을 이용하여 고성능 장애물 탐지를 위한 중첩 초음파 센서 링을 최적 설계하는 방법에 대해 체계적으로 기술하도록 한다. 기본적으로 일군의 동종 저지향성 초음파 센서들이 일정 간격으로 상호 빔 폭이 중첩되도록 원형 배치된다고 가정한다. 첫째 초음파 센서의 실제와 단순화된 빔 패턴 그리고 빔 폭 내의 장애물 위치 추정을 위한 여러 센서 모델에 대해 소개한다. 둘째, 중첩 초음파 센서 링의 장애물 탐지 범위와 장애물 위치 추정을 위한 간단한 센서 모델에 대해 기술한다. 셋째, 타원과 비타원 형태의 빔 패턴에 대해 각각, 장애물 탐지 시 위치 불확실성이 최소화되도록 중첩 초음파 센서 링을 설계하기 위한 지수를 정의한다. 넷째, 최소한의 빔 폭 중첩 보장과 과도한 빔 폭 중첩 회피를 위해 요구되는 중첩 초음파 센서 링의 구조적 사양에 대한 제한 조건을 유도한다. 다섯째, 주어진 중첩 초음파 센서 링의 반경에 대한 초음파 센서의 최적 사용 개수와 주어진 초음파 센서의 사용 개수에 대한 중첩 초음파 센서 링의 최적 반경을 결정한다. 본 논문 전반에 걸쳐, 대표적인 상용 저지향성 초음파 센서로서 Murata사의 MA40B8이 채택되었다. This paper presents the systematic optimal design of an overlapped ultrasonic sensor ring for high performance obstacle detection using effective beam overlap. Basically, a set of low directivity ultrasonic sensors of the same type are arranged in a circle at regular intervals with their beams overlapped. First, both real and simplified beam patterns of an ultrasonic sensor and several sensor models for obstacle position estimation within its beam pattern are introduced. Second, the obstacle detection range of an overlapped ultrasonic sensor ring and its simple sensor model for obstacle position estimation are described. Third, for both conic and non-conic shaped beam pattern, the design indices of an overlapped ultrasonic sensor ring for minimal positional uncertainty in obstacle detection are defined. Fourth, the constraints imposed on the structural parameters of an overlapped ultrasonic sensor ring to guarantee non empty beam overlap and to avoid excessive beam overlap are derived. Fifth, the optimal number of ultrasonic sensors for a given radius of an overlapped ultrasonic sensor ring and the optimal radius of an overlapped ultrasonic sensor ring are determined. Throughout this paper, the MA40B8 from Murata Inc. is taken as a representative commercial low directivity ultrasonic sensor.

고분해능 장애물 탐지를 위한 중첩 초음파 센서 링의 최적 설계

김성복,김현빈,Kim, Sung-Bok,Kim, Hyun-Bin 제어로봇시스템학회 2011 제어·로봇·시스템학회 논문지 Vol.17 No.2

This paper presents the optimal design of an overlapped ultrasonic sensor ring for high resolution obstacle detection of an autonomous mobile robot. It is assumed that a set of low directivity ultrasonic sensors of the same type are arranged along a circle of nonzero radius at a regular spacing with their beams overlapped. First, taking into account the dead angle region, the entire range of obstacle detection is determined with reference to the center of an overlapped ultrasonic sensor ring. Second, the optimal design index of an overlapped ultrasonic sensor ring is defined as the area closeness of three sensing subzones resulting from beam overlap. Third, the lower and upper bounds on the number of ultrasonic sensors are derived, which can guarantee minimal beam overlap and also avoid excessive beam overlap among adjacent ultrasonic sensors. Fourth, employing a commercial low directivity ultrasonic sensor, an optimal design example of an overlapped ultrasonic sensor ring is given along with the ultrasonic sensor ring prototype mounted on top of a mobile robot. Finally, some experimental results using our prototype ultrasonic sensor ring are given to demonstrate the validity and performance of an optimally overlapped ultrasonic sensor ring for high resolution obstacle detection.

초음파 센서를 이용한 시험설비 정확도 향상 시스템

우동명(Dong-myung Woo),김동선(Dong-seon Kim),류장렬(Jang-Ryeol Ryu) 한국정보기술학회 2019 Proceedings of KIIT Conference Vol.2019 No.6

본 연구는 초음파 센서(Ultrasonic Sensor)와 라즈베리파이(Raspberry Pi)를 사용하여 근무 중인 회사 내 노후화된 시험설비의 정확도 향상을 위한 시스템을 개발하고자 하는 목표이다. 이를 위해 라즈베리파이3, 초음파센서, 온습도 센서 등을 연결하여 시스템을 구성하였다. 또한 초음파 센서와 온습도 센서의 측정확도 향상을 위하여 자체 교정을 진행 후 보간법을 사용하였고, 온도의 변화에 따른 초음파 센서 거리 측정 오차를 줄이기 위하여 온도를 측정하여 온도에 따른 초음파 센서 거리 계산 함수를 추가하였다. 추가로 모니터링 시스템은 html로 코드를 작성하여 시험자는 운영체제 및 웹브라우저에 상관없이 모니터링이 가능하여 회사 시험실 내 어디서든 실시간으로 시험설비의 상태를 알 수 있다. 본 연구를 통해 시험자는 스로틀 위치를 정량적으로 확인할 수 있었으며, 후단팬의 사용 불가 영역을 회피하여 시험 설비의 정확도 및 안정도 향상을 도모하였다. The purpose of this study is to develop a system for improving the accuracy of the aging test equipment in the company using ultrasonic Sensors and raspberry Pi. For this purpose, the system was constructed by connecting Raspberry Pi 3, ultrasonic sensors, and temperature and humidity sensor. In order to improve the accuracy of the ultrasonic sensors and the temperature and humidity sensor, the interpolation method is used after the self calibration. In order to reduce the measurement error of the ultrasonic sensors according to the temperature change, the temperature is measured and the ultrasonic sensor distance calculation function according to temperature is added. In addition, the monitoring system writes code in html, allowing the tester to monitor the operating system and web browser regardless of the status of the test facility from anywhere in the company laboratory. Through this study, the tester was able to confirm the throttle position quantitatively and avoid the unusable area of the rear fan, thereby improving the accuracy and stability of the test equipment.

중첩 초음파 센서 링 최적 설계 시 기하학적 고려 사항

김성복(Sungbok Kim),김현빈(Hyunbin Kim) 제어로봇시스템학회 2010 제어로봇시스템학회 각 지부별 자료집 Vol.2010 No.12

This paper presents the geometric constraints in the optimal design of an overlapped ultrasonic sensor ring. It is assumed that a set of ultrasonic sensors of the same type are arranged in a circle of nonzero radius at a regular spacing with their beams overlapped. For effective beam overlap of an overlapped ultrasonic sensor ring, it is required to guarantee non empty beam overlapping between adjacent ultrasonic sensors and also to avoid excessive beam overlapping among adjacent ultrasonic sensors. First, for a given radius of an overlapped ultrasonic sensor ring, the restriction on the number of ultrasonic sensors for effective beam overlap is analyzed. Then, for a given number of ultrasonic sensors, the restriction on the radius of an overlapped ultrasonic sensor ring is analyzed.

LOW COST DESIGN OF PARALLEL PARKING ASSIST SYSTEM BASED ON AN ULTRASONIC SENSOR

S. H. JEONG,C. G. CHOI,J. N. OH,P. J. YOON,B. S. KIM,M. KIM,이쾌희 한국자동차공학회 2010 International journal of automotive technology Vol.11 No.3

This paper presents a low cost design and implementation of a parallel parking assist system (PPAS) based on ultrasonic sensors. Generally, a PPAS requires several types of sensors, such as an ultrasonic sensor, camera sensor, radar sensor and laser sensor for parking space detection. However, our proposed PPAS only requires two ultrasonic sensors on the front and lateral sides for parking space detection. Moreover, a steering angle sensor and wheel speed sensor installed in the vehicle are used to obtain vehicle position information for localization in ultrasonic range data. The hardware architecture of the PPAS based on an electronic control unit (ECU) module, sensor modules and a human machine interface (HMI) module was proposed. Moreover, the software architecture of the PPAS is based on system initialization, scheduling, recognition and a control algorithm. In particular, a novel sensor algorithm was proposed to minimize the vehicle corner error of the ultrasonic sensor. A prototype of the PPAS based on the proposed architecture was constructed. The experimental results demonstrate that the implemented prototype is robust and successfully performs parking space detection and automatic steering control. Finally, the low cost design and implementation of the PPAS was possible due to the cheap ultrasonic sensors, simple hardware design and low computational complexity of the proposed algorithm.

Miniature Ultrasonic and Tactile Sensors for Dexterous Robot

Okuyama, Masanori,Yamashita, Kaoru,Noda, Minoru,Sohgawa, Masayuki,Kanashima, Takeshi,Noma, Haruo The Korean Institute of Electrical and Electronic 2012 Transactions on Electrical and Electronic Material Vol.13 No.5

Miniature ultrasonic and tactile sensors on Si substrate have been proposed, fabricated and characterized to detect objects for a dexterous robot. The ultrasonic sensor consists of piezoelectric PZT thin film on a Pt/Ti/$SiO_2$ and/or Si diaphragm fabricated using a micromachining technique; the ultrasonic sensor detects the piezoelectric voltage as an ultrasonic wave. The sensitivity has been enhanced by improving the device structure, and the resonant frequency in the array sensor has been equalized. Position detection has been carried out by using a sensor array with high sensitivity and uniform resonant frequency. The tactile sensor consists of four or three warped cantilevers which have NiCr or $Si:B^+$ piezoresistive layer for stress detection. Normal and shear stresses can be estimated by calculation using resistance changes of the piezoresitive layers on the cantilevers. Gripping state has been identified by using the tactile sensor which is installed on finger of a robot hand, and friction of objects has been measured by slipping the sensor.

Positional Uncertainty Assessment and Complex Obstacle Detection of an Ultrasonic Sensor Ring with Overlapped Beam Pattern

Sungbok Kim,Hyunbin Kim 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

This paper presents the positional uncertainty assessment and the complex obstacle detection of an ultrasonic sensor ring with overlapped beam pattern. Due to beam overlap between adjacent ultrasonic sensors, the entire sensing range of an individual ultrasonic senor can be divided into three smaller sensing subzones. First, the concept of collision free region of each ultrasonic sensor with reference to the center of an ultrasonic sensor ring is introduced. Second, the effective beam width of an overlapped ultrasonic sensor ring is defined to assess the positional uncertainty in obstacle detection. Third, high resolution single obstacle detection can be made based on the combination of two adjacent ultrasonic sensors detecting a given obstacle. Fourth, high resolution multiple obstacle detection can be made based on the inequality relationships among the obstacle distances by three consecutive ultrasonic sensors.

Miniature Ultrasonic and Tactile Sensors for Dexterous Robot

Masanori Okuyama,Kaoru Yamashita,Minoru Noda,Masayuki Sohgawa,Takeshi Kanashima,Haruo Noma 한국전기전자재료학회 2012 Transactions on Electrical and Electronic Material Vol.13 No.5

Miniature ultrasonic and tactile sensors on Si substrate have been proposed, fabricated and characterized to detect objects for a dexterous robot. The ultrasonic sensor consists of piezoelectric PZT thin film on a Pt/Ti/SiO2 and/or Si diaphragm fabricated using a micromachining technique; the ultrasonic sensor detects the piezoelectric voltage as an ultrasonic wave. The sensitivity has been enhanced by improving the device structure, and the resonant frequency in the array sensor has been equalized. Position detection has been carried out by using a sensor array with high sensitivity and uniform resonant frequency. The tactile sensor consists of four or three warped cantilevers which have NiCr or Si:B+ piezoresistive layer for stress detection. Normal and shear stresses can be estimated by calculation using resistance changes of the piezoresitive layers on the cantilevers. Gripping state has been identified by using the tactile sensor which is installed on finger of a robot hand, and friction of objects has been measured by slipping the sensor.