Trajectory design and dispersion analysis of nano moon lander OMOTENASHI

• Published in: Acta astronautica 2023-12, Vol.213, p.665-675
• Main Authors: Kikuchi, Junji, Hirose, Chikako, Morishita, Naoki, Hirasawa, Ryo, Tokunaga, Kakeru, Bando, Nobutaka, Hashimoto, Tatsuaki
• Format: Article
• Language: English
• Subjects: CubeSat; Landing site dispersion; Landing success rate; Moon lander; SLS rocket; Trajectory correction
• ISSN: 0094-5765; 1879-2030
• DOI: 10.1016/j.actaastro.2023.09.019

OMOTENASHI is a CubeSat that was launched by a NASA SLS rocket. Its mission was to demonstrate that a CubeSat could make a semi-hard landing on the Moon. A chemical propulsion system which provides high thrust and can be re-ignited is large and difficult to install on a CubeSat. Therefore, a small cold-gas jet makes orbit corrections with only a small ΔV. Moreover, a rocket motor with a high Isp and structural mass ratio is used for a lunar landing deceleration. The spacecraft consists of an orbiting module, a rocket motor, and a surface probe. This paper analyzes the trajectory design of the Moon landing and a method that increases the landing success rate under the tight constraints of the CubeSat. To reduce fuel and power consumption, the maneuver conditions during the lunar transition to reach the target landing site are evaluated based on several error factors. This study considers the trade-off between vertical and horizontal landings. Because active control is not possible for decelerating a rocket motor for the lunar landing, the optimal altitude at the starting maneuver is determined by considering such errors as attitude and timing. Finally, the paper discusses mission feasibility and the landing success rate. •OMOTENASHI was developed as the world's smallest moon lander that was launched by a NASA SLS rocket.•OMOTENASHI uses Rocket Motor to decelerate Surface Probe for a semi-hard landing.•This paper shows an innovative trajectory design method of the moon landing for a CubeSat as a secondary payload.•For a high landing success rate, the CubeSat must accommodate many constraints in selecting the landing site.•This method can be utilized for future CubeSat missions under tight resource constraints, such as a thrust and a power consumption.