Abstract CAS500-1 (Compact Advanced Satellite 500-1) launched in Mar. 2021 is the first Korean ground observation satellite localizing entire mirror development, especially primary M1. M1 a lightweight concave with diameter of 0.6 m, and it has 3 square bosses at rim for flexure mounting. We present whole development procedure flight model M1, including optomechanical design, fabrication, envir...

Micro aerial vehicles (MAVs) pose specific constraints on onboard sensing, mainly limited payload and limited processing power. For accurate 3D mapping even in GPS denied environments, we have designed a light-weight 3D laser scanner specifically for the application on MAVs. Similar to other custom-built 3D laser scanners composed of a rotating 2D laser range finder, it exhibits different point...

Increased ocular positioning misalignments upon exposure to altered gravity levels (g-levels) have been strongly correlated with space motion sickness (SMS) severity, possibly due to underlying otolith asymmetries uncompensated in novel gravitational environments. We investigated vertical and torsional ocular positioning misalignments elicited by the 0 and 1.8 g g-levels of parabolic flight and...

Micro aerial vehicles (MAVs) pose specific constraints on onboard sensing, mainly limited payload and limited processing power. For accurate 3D mapping even in GPS-denied environments, we have designed a lightweight 3D laser scanner specifically for the application on MAVs. Similar to other custom-built 3D laser scanners composed of a rotating 2D laser range finder, it exhibits different point ...

This paper presents a method for on-orbit calibration of photodiodes for sun sensing in an attitude determination system. The calibration estimates the scale factors and alignment angles of the photodiodes, resulting in higher attitude determination accuracy than achieved with the pre-flight calibration parameters. The calibration is implemented with an extended Kalman filter to simultaneously ...

Micro-Doppler (MD) caused by the motion of the ballistic missile can contribute to successful recognition of the ballistic missile. Considering the real observation scenario. This paper proposes a method to derive the MD image of the ballistic missile by applying the range-Doppler algorithm (RDA) based on the real flight scenario and analyzes the factor for the real-time MD imaging. Simulation ...

This paper presents a design and simulation of the functions of a Flight Management System (FMS) in order to follow automatically four-dimensional trajectories. This is achieved by controlling the aircraft airspeed, altitude, heading and vertical speed in order to arrive to the merging point in the specified time. The system receives data from the aircraft and computes new control parameters ba...

Difference in differences (DID) require that the treatment rate is equal to 0% in the control group and during period 0 (no “always takers”) and to 100% in the treatment group in period 1 (no “never takers”). Sometimes, treatment rate increases more in the treatment than in the control group but there are never or always takers. This paper derives identification results applying to such setting...

The optical alignment of the star trackers on the Global Precipitation Measurement (GPM) core spacecraft at NAS A Goddard Space Flight Center (GSFC) was challenging due to the layout and structural design of the GPM Lower B us Structure (LBS) in which the star trackers are mounted as well as the presence of the star tracker shades that blocke d line-of-sight to the primary star tracker optical ...