• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.46 no.2
• /
• pp.28-35
• /
• 2009

Positioning technology which a part technology of Mobile Robot is an essential technology to locate the position of Robot and navigate to wanted position. The Robot that based on wheel drive uses Odometry position. technology. But when using Odometry positioning technology, it's hard to find out constant error value because a slip phenomenon occurs as the Robot runs. In this paper, we present the way to minimize positioning error by using Odometry and Inertial sensor. Also, the way to reduce error with Inertial sensor on SLAM using image will be shown, too.

• Journal of Advanced Navigation Technology
• /
• v.20 no.4
• /
• pp.314-320
• /
• 2016

Inertial navigation system (INS) has used aided systems and sensors to compensate navigation error. Global navigation satellite system (GNSS), velocity measurement sensor (VMS), and radar are commonly used to aid INS. Land navigation system (LNS) also mainly uses VMS when GNSS cannot be used such as at tunnel or on jammed scenario. A straight drive is required when VMS-aided navigation is used, because there is only speed of straight direction whereas no crossways and vertical directions. In local environment, even an expressway has lack of straight drive which is constraint of VMS-aided navigation algorithm. This paper proposes an enhanced VMS-aided navigation algorithm for LNS with indirect drive by restricting filter update condition. Also, there is a result of vehicle test to prove performance of the proposed algorithm.

• Aerospace Engineering and Technology
• /
• v.9 no.2
• /
• pp.36-43
• /
• 2010

A GEO satellite launched by Arian 5 ECA launcher will be located in a transfer orbit where it requires several Apogee burn maneuvers to reach the target orbit. To obtain the required performance of Apogee burn maneuvers, a calibration of gyro drift error needs to be performed before each maneuver. In this paper, a unique gyro calibration scheme which is applied to COMS is described and the calibration error budget analysis is performed.

• Korean Journal of Construction Engineering and Management
• /
• v.22 no.3
• /
• pp.40-51
• /
• 2021

MLS (Mobile Laser Scanning) which is a scanning method done by moving the LiDAR (Light Detection and Ranging) is widely employed to capture indoor PCD (Point Cloud Data) for floor plan generation in the AEC (Architecture, Engineering, and Construction) industry. The movement and rotation of LiDAR in the scanning phase cause deformation (i.e. skew) of PCD and impose a significant impact on quality of output. Thus, a de-skewing method is required to increase the accuracy of geometric representation. De-skewing methods which use position and pose information of LiDAR collected by IMU (Inertial Measurement Unit) have been mainly developed to refine the PCD. However, the existing methods have limitations on de-skewing PCD without IMU. In this study, a novel algorithm for de-skewing 2D PCD captured from MLS without IMU is presented. The algorithm de-skews PCD using scan matching between points captured from adjacent scan positions. Based on the comparison of the deskewed floor plan with the benchmark derived from TLS (Terrestrial Laser Scanning), the performance of proposed algorithm is verified by reducing the average mismatched area 49.82%. The result of this study shows that the accurate floor plan is generated by the de-skewing algorithm without IMU.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.4
• /
• pp.380-388
• /
• 2023

This study estimates the metacentric height (GM) of a model ship by varying the transverse weight distribution, considering the effects of the roll period and moment of inertia, and compares it with the GM values measured by the inclining test. In the process, the relationship between the values is analyzed. Three types of ships-a 7-ton fishing vessel, 20-ton fishing vessel, and KRISO Very Large Crude-oil Carrier (KVLCC)-were used for the experiment and comparison. The roll period and moment of inertia were measured using the free roll decay and swing frame tests, and the GM was measured using inclining test. The estimated GM from the roll period and moment of inertia showed the same trend as the GM measured using the inclining test in the change of the weight distribution. However, the GM values measured using the inclining test were lower. Therefore, additional correction factors or parameters other than the roll period and moment of inertia are necessary for estimating GM. In the future, the relationship between the weight center and the estimated GM will be analyzed to derive the correction factors.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.11
• /
• pp.159-166
• /
• 2012

There are several ways such as GPS(Global Positioning System) and INS (Inertial Navigation System) to track the location of moving vehicle. The GPS has the advantages of having non-accumulative error even if it brings about errors. In order to obtain the position information, we need to receive at least 3 satellites information. But, the weak point is that GPS is not useful when the 혠 signal is weak or it is in the incommunicable region such as tunnel. In the case of INS, the information of the position and posture of mobile with several Hz~several hundreds Hz data speed is recorded for velocity, direction. INS shows a very precise navigational performance for a short period, but it has the disadvantage of increasing velocity components because of the accumulated error during integration over time. In this paper, sensor fusion algorithm is applied to both of INS and GPS for the position information to overcome the drawbacks. The proposed system gets an accurate position information from experiment using SVD in a non-accessible GPS terrain.

• Journal of Institute of Control, Robotics and Systems
• /
• v.9 no.6
• /
• pp.420-424
• /
• 2003

A new adaptive filter is proposed for an aided strapdown inertial navigation system(SDINS). The proposed filter can be used to effectively estimate the time-varying variance of the measurement noise. Then, the in-flight alignment for the radar aided SDINS is designed using the additive quatermion error model. Simulation results show that the proposed adaptive filter effectively improves the performance of the radar aided SDINS.

• Journal of Institute of Control, Robotics and Systems
• /
• v.12 no.5
• /
• pp.509-515
• /
• 2006

This paper presents a navigation error compensation scheme for Strap-Down Inertial Navigation System(SDINS) using electro-optical sensor. The proposed scheme uses the position or the attitude information from the sensor. For each case, Kalman filter model is derived and implemented. To show the effectiveness of the present compensation scheme, computer simulations have been carried out resulting in the boundedness of position and attitude errors.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.10a
• /
• pp.94-95
• /
• 2017

지정된 경로에서 6축 센서의 가속도와 각속도를 이용하여 물체의 이동거리를 계산하는 경우 가속도 센서에서 나오는 데이터는 중력을 사용하여 값을 보내주는데, 평평한 상태에서는 중력가속도만 나오므로 영향이 없지만 물체가 움직이면서 기울어지거나 흔들리는 경우 중력가속도와 운동가속도가 더해지고 이에 따라 이동거리 계산에 오차가 발생한다. 이 논문에서는 가속도와 각속도만으로 보정이 힘들다고 판단하여 적외선 센서를 사용하여 이동거리를 산출하는 방법을 제안하고 시스템을 개발한다. 제안한 시스템은 지정된 경로를 따라 이동할 때 적외선 센서를 이용하여 궤도의 구분선을 인식하여 기존 6축 센서로 계산된 이동거리를 보정한다.

• Proceedings of the KIEE Conference
• /
• 2001.07d
• /
• pp.1946-1948
• /
• 2001

본 논문에서는 저급 관성 센서를 이용한 개인 항법 장치의 모델 및 오차 보정 기법을 제시하고 성능 평가를 위하여 시뮬레이션을 수행하였다. 걸음 검출에 의한 보행 항법에서 중요한 변수인 보폭은 신경 회로망(Neural Network)을 이용하여 결정하였고, 자이로 바이어스 등에 의하여 누적되는 오차는 GPS와의 결합에 의하여 추정, 보상하였다. 이때 GPS와의 결합은 칼만필터를 이용하였으며 칼말필터를 구성하는데 필요한 오차 모델 및 결합 방법을 제시하였다. WNS/GPS 결합에 의하여 오차의 발산을 막을 수 있으며 GPS신호가 중간에 단절되는 경우에도 오차가 발산하지 않고 좋은 결과를 유지함을 보인다.