• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.6
• /
• pp.532-538
• /
• 2010

SD (Smart Door) is a human friendly power-assisted door system initially targeted for passenger car doors. The Smart Door offers comfort and safety to passengers or/and drivers by supplying additional power. Amount of power supplied by the Smart Door system is depend on the environment where the automotive is situated. It realizes comfort, for example, when the force applied by the passenger to the door is expected to be abnormal, the SD system tries to compensate passenger's effort by supplying additional force. In this study, to enhance the ease of opening and closing the doors of the passenger vehicle, a Smart Door with a power assist mechanism consisting of a motor was developed and analysed. A power assist mechanism mounted within the vehicle's door is designed and modeled for simulation purpose. The required force necessary to control the designed mechanism during the vehicle's roll, pitch and the opening angle of the door has been considered. To this end, we propose a power-assisting control strategy called "gravity cancellation". The system is analysed by numerical simulation with the gravity cancellation control algorithm.

• The Bulletin of The Korean Astronomical Society
• /
• v.36 no.1
• /
• pp.34.2-34.2
• /
• 2011

In this talk we explain U-loop emergence, in which U-shaped field lines emerge into the solar surface against gravitational force. In principle, they hardly emerge because mass tends to accumulate at the bottom of U-loops, thereby decreasing buoyancy. A key is found to be the shape of U-loops, that is, if U-loops have a shallow dip whose depth is of the order of the photospheric gravitational scale height, then a diverging flow is generated via a siphon-like mechanism by which the mass accumulated at the dip of the loops is drained out to enhance buoyancy. This successfully makes U-part of the loops emerge against gravity. We also discuss the relation between U-loop emergence and the so-called flux cancellation observed on the Sun in which opposite polarity regions apparently approach together and disappear.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.21 no.5
• /
• pp.40-46
• /
• 2013

Automatic swing door for an automotive application is considered. The equation of motion for a driver side swing door is introduced and gravity cancellation control scheme is adapted. The control scheme supposed to cancel the moment due to the tilt of the car. A speed control is suggested for door operation automation but the output of the speed control is not suppose to be precise as for the manufacturing system control. In the frame of the velocity control of the door, feedback linearization was applied for collision detection. The collision detection performance is satisfactory. The estimate of the magnitude of disturbance due to the collision is close to the actual magnitude of disturbance. Simulation study has been performed to gain insight into the system behavior. Also real test on the prototype hardware has been performed for verification purpose.

• Journal of Advanced Navigation Technology
• /
• v.28 no.4
• /
• pp.379-385
• /
• 2024

INS(inertial navigation system) aligns itself using gravity and Earth's rotational rate from accelerometers and gyro sensors when stationary. Typically, ZUPT(zero velocity update), which is based on a linear error model Kalman filter, is used when it is stationary. However, such algorithms assume stationary conditions, leading to increased alignment errors or filter divergence during maritime mooring due to wave-induced motion. This paper designs a mooring alignment algorithm for maritime platforms using a Kalman filter, which uses large heading angle error model and an initial position correction technique. And it is validated by simulation. Furthermore, it is confirmed that applying this to a rotational INS dramatically improves performance through the principle of bias cancellation.