BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//6.6.4.4//EN TZID:Asia/Jerusalem X-WR-TIMEZONE:Asia/Jerusalem BEGIN:VEVENT UID:0-300@aerospace.technion.ac.il DTSTART;TZID=Asia/Jerusalem:20200106T163000 DTEND;TZID=Asia/Jerusalem:20200106T173000 DTSTAMP:20230527T131259Z URL:https://aerospace.technion.ac.il/events/sub-optimal-spatial-guidance-u nder-angular-constraint-in-aerodynamic-flight/ SUMMARY:Sub-Optimal Spatial Guidance under Angular Constraint in Aerodynami c Flight DESCRIPTION:Lecturer:Nahshon Indig\n Faculty:Department of Aerospace Engine ering\n Institute:Technion – Israel Institute of Technology\n Location:C lassroom 165\, ground floor\, Library\, Aerospace Eng.\n Zoom: \n Abstract : \n Details: \n The purpose of the study is to develop optimal spatial gu idance-laws under terminal angular constraint in atmospheric flight\, whic h enable the pursuer to reach its target under various optimization object ives criteria (minimum time\, maximum velocity or minimum acceleration eff ort)\, using the traditional acceleration controller\, the thrust controll er or a combination of both. The research considers several guidance relat ed problems\, focusing on developing numerical\, empirical and analytical methods for analyzing and solving these problems. In this area of guidance laws with terminal angular constraint\, most of the existing studies have been performed under various accumulating assumptions (engagement geometr y is linearized\, the interceptor is near the collision course and the dyn amics are for a vacuum flight) which created a gap between the terms of th e studies and the real flight conditions.\nIn the first part\, a novel nea r optimal closed-loop guidance law is introduced with maximum velocity cri teria for the 2D nonlinear problem under terminal angular constraint (base d on the linear solution) with performances matching the optimal results v ery closely. In the second stage\, this law is extended to the spatial (3D ) case\, by determining the preferred spatial maneuver plane based on ener gy consideration.\nIn the second part\, the spatial problem with 'minimum- time' optimization objective criteria under terminal  angular manifold co nstraint (known as Dubbin’s problem) is solved. The study expands the pr oblem to a more difficult case: minimum time arrival with a terminal conic al manifold constraint and suggests a near-optimal closed-loop guidance ap proach to address the 3D problem with time-varying speed  and optimal clo sed-loop guidance approach for vacuum flight.\nIn the third part\, the fam ous Goddrad problem with various optimization objectives criteria is addre ssed\, where the controller is the thrust input that replaces the traditio nal acceleration controller. This is a known singular control problem. Suc h problems are usually characterized by solutions that are difficult to fo rmulate. Previous research generally showed partial solutions to the Godda rd problem. The proposed solution formulates the analytical thrust control ler in closed loop for various variations of 1D and 2D Goddard problems un der different trajectory bending laws. The proposed method can be implemen ted for other singular control problems in various branches of science.\nI n the fourth part\, the study is focused on the 2D non-linear problem unde r angular constraints and with various optimization objectives employing t wo controllers: the thrust controller and the acceleration controller. Thi s problem has been discussed minimally in the literature. The main innovat ion in this part is the emphasis of the improvement performances potential when using the two controllers in parallel. A convex Pareto curve (in two optimization objectives) including all optimal solutions is obtained. Add ing Leitmann’s test for necessary conditions for Pareto-Optimality enabl es to deepen the understanding obtained from the optimal solutions in this complicate case. CATEGORIES:Seminars LOCATION:Classroom 165\, ground floor\, Library\, Aerospace Eng. END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Jerusalem X-LIC-LOCATION:Asia/Jerusalem BEGIN:STANDARD DTSTART:20191027T010000 TZOFFSETFROM:+0300 TZOFFSETTO:+0200 TZNAME:IST END:STANDARD END:VTIMEZONE END:VCALENDAR