Development of Optimal Guidance and Adaptive Algorithm for Vertical Landing Vehicle

1.(1) 2002 ~ 2003年，研究了月球着陆器垂直着陆和软着陆的最优制导律，并在2002年和2003年在韩国举行的ICCAS会议上发表了研究结果。b)在假定月球着陆器运动方程为线性的前提下，从理论上推导了一种新的最小抖动最优制导律，并将其仿真结果于2004年提交给了日本航空航天学会学报。关于这方面的一篇文章将刊登在第48卷第1期。这笔交易在2005年达到了159美元。c) 2004年，假设再入飞行器的运动是非线性的，采用精确线性化的方法，利用之前得到的最小抖动最优制导律，建立了新的制导律。该研究结果也被提交给了《日本航空与空间科学学会杂志》，并将于2004年夏天在该杂志上发表。多板实时仿真为了验证上述最优制导律的有效性，利用多板dsp进行了实时仿真。在仿真中，研究了有限字长、离散化引起的限零问题、计算时延和测量噪声对控制系统的影响，特别是对限零问题进行了理论分析，阐明了采样时间与限零问题的关系；通过回顾从六度代数方程的实数解中选择最优运行时间解的提取过程，进行了更精确的模拟。d)最后，在考虑实际传感器规格的仿真中，发现测量噪声会导致终端（目标点）的下程误差最多偏离12 m；然而，它对燃料消耗的影响是微不足道的。这一结果于2004年3月在日本航空与空间科学学会的国内会议上发表。少

1.Development of optimal guidance lawa)From 2002 to 2003, an optimal guidance law was investigated for the vertical and soft landing of a lunar lander, and obtained results were presented at the ICCAS conferences held in Korea in 2002 and 2003. b)A novel minimum jerk optimal guidance law was theoretically developed by assuming that the equation of motion of the Lunar lander was linear, and was submitted to the Transactions of the Japan Society for Aeronautical and Space Sciences with its simulation results in 2004. An article on this will appear in Vol.48,No.159 of this transaction in 2005. c)In 2004, by assuming that the motion of a reentry vehicle was nonlinear, a new guidance law was developed using an exact linearization method with the previously obtained minimum jerk optimal guidance law. The result was also submitted to the Journal of the Japan Society for Aeronautical and Space Sciences and will appear in this journal in the summer of 2004.2.Real time simulation using muti-DSP … More boardsa)A real time simulation was carried out using multi-DSP boards in order to confirm the validity of the above- mentioned optimal guidance law. In this simulation, the effects of finite-word length, a limiting-zero problem due to discretization, computational time delay, and measurement noise on the control system were examined, b)In particular, a theoretical analysis of the limiting-zero problem was carried and the relationship between the sampling time and the limiting-zero problem was clarified, c)Furthermore, a more precise simulation was carried out by reviewing the extraction process in which an optimal time-to-go solution was chosen from the real number solutions obtained from a six-degree algebraic equation with respect to time-to-go. d)Lastly, in the simulation in which actual sensor specifications were considered, the measurement noise was revealed to cause the downrange error to deviate at most 12 m at the terminal point (target point) ; however, its effect on fuel consumption was negligible. This result was presented at a domestic conference of the Japan Society for Aeronautical and Space Sciences in March, 2004. Less