Презентация к семинару кафедры теоретической механики. По материалам статьи “Detumbling Space Debris Using Modified Yo-Yo Mechanism” (Юдинцев В. В.,
Асланов В. С.) Journal of Guidance, Control, and Dynamics, Vol. 40, No. 3. https://arc.aiaa.org/doi/abs/10.2514/1.G000686
(2017), pp. 714-721.
Презентация к семинару кафедры теоретической механики. По материалам статьи “Detumbling Space Debris Using Modified Yo-Yo Mechanism” (Юдинцев В. В.,
Асланов В. С.) Journal of Guidance, Control, and Dynamics, Vol. 40, No. 3. https://arc.aiaa.org/doi/abs/10.2514/1.G000686
(2017), pp. 714-721.
Children learn language differently than adults due to their developmental stage. Young learners have certain characteristics that influence their language learning, such as shorter concentration spans and a focus on meaning over individual words. The teacher's focus should be on communication and enjoyment to promote achievement using activities that make the most of learners' instincts, creativity, and pleasure in fun. It is counterproductive to rely heavily on the mother tongue in class.
TPR, or Total Physical Response, is a language teaching method that uses physical movement in response to verbal commands to help reduce stress associated with language learning. It is based on how infants acquire their first language through comprehending and then producing responses. Using TPR, students first focus on comprehending commands and responding physically before being asked to respond verbally. The method encourages students to perform physical activities in response to commands given by the teacher in the target language to help students internalize vocabulary and grammar structures in a stress-free, comprehensible way similar to first language acquisition.
The document describes the Total Physical Response (TPR) method of foreign language instruction. It focuses on listening comprehension in the early stages by having students respond physically to verbal commands without speaking. The teacher models commands and students mimic the actions. Over time, students begin speaking by giving their own commands. The goal is to reduce anxiety and make learning enjoyable through physical engagement with the language.
This document discusses learning styles and strategies. It begins by outlining the objectives and sequence of topics to be presented. These include how people learn through visual, auditory and tactile means. It then provides background on learning styles and strategies based on the work of psychologists Jung and Piaget. Key definitions are given for learning styles as natural habitual preferences for absorbing information and strategies as characteristics teachers stimulate in students. The importance of understanding learning styles for diverse classrooms is highlighted. Various types of learning styles are then described, including cognitive, sensory and personality styles. Finally, principles for teaching different styles and strategies are outlined.
This document outlines the four main learning styles identified in Kolb's learning styles theory: activist, reflector, theorist, and pragmatist. The activist learns by doing activities like brainstorming and role-playing. The reflector learns by observing and thinking, preferring activities like questionnaires and feedback. The theorist learns by understanding theories behind actions through models and stories. The pragmatist learns by applying ideas in real-world practice through case studies and problem-solving. The document provides strengths and weaknesses of each style.
Leveraging Your Learning Style & Effective Study Strategies
Do you know how you learn best?
Your learning style is the way you prefer to learn. It doesn't have anything to do with how intelligent you are or what skills you have learned. It has to do with how your brain works most efficiently to learn new information. This workshop will focus on helping you identify your own learning style and show you how to develop learning strategies that work for you so you can create a customized approach to achieving academic success.
Total Physical Response (TPR) is a language teaching method developed by Dr. James Asher based on his observations of how children acquire their first language. TPR teaches language through physical actions in response to verbal commands. Students listen and then perform actions commanded by the instructor in the target language without having to vocally respond themselves. TPR is often used with beginners and young learners to develop listening comprehension and vocabulary through coordinated speech and movement before introducing speaking.
The document discusses the Total Physical Response (TPR) language teaching method developed by Dr. James Asher in the 1970s. TPR uses physical movement and actions in response to verbal commands to help lower students' stress levels and increase comprehension when learning a new language. It places emphasis on listening skills before speaking. The method focuses on meaning over form and uses activities like imperative drills, role playing, and materials like pictures. TPR is best suited for basic language acquisition in beginner students through a stress-free environment.
The document discusses different learning styles, including the visual learning style. It describes the VAK model which categorizes learners as visual, auditory, or kinesthetic based on how they receive and process information. Visual learners tend to observe things like pictures, demonstrations, and films in order to improve their knowledge. They understand written instructions better than oral ones and use highlighting, color coding, mind maps and other visual techniques to memorize information.
This document discusses learning styles and how understanding your own learning style can help you learn more effectively. There are three main learning styles: visual, which involves seeing and reading; auditory, which involves listening and talking; and kinesthetic/tactile, which involves hands-on activities. The document provides examples of how each type prefers to learn and techniques to help with learning for each style, such as using pictures for visual learners or discussing material aloud for auditory learners. Understanding your dominant learning style can improve productivity, achievement, problem solving and learning overall.
Рассматривается метод отдельных тел (метод А. Ф. Верещагина) для построения уравнений движения систем тел со структурой дерева. Приводится пример программы моделирования движения цепи n тел на языке MATLAB.
Children learn language differently than adults due to their developmental stage. Young learners have certain characteristics that influence their language learning, such as shorter concentration spans and a focus on meaning over individual words. The teacher's focus should be on communication and enjoyment to promote achievement using activities that make the most of learners' instincts, creativity, and pleasure in fun. It is counterproductive to rely heavily on the mother tongue in class.
TPR, or Total Physical Response, is a language teaching method that uses physical movement in response to verbal commands to help reduce stress associated with language learning. It is based on how infants acquire their first language through comprehending and then producing responses. Using TPR, students first focus on comprehending commands and responding physically before being asked to respond verbally. The method encourages students to perform physical activities in response to commands given by the teacher in the target language to help students internalize vocabulary and grammar structures in a stress-free, comprehensible way similar to first language acquisition.
The document describes the Total Physical Response (TPR) method of foreign language instruction. It focuses on listening comprehension in the early stages by having students respond physically to verbal commands without speaking. The teacher models commands and students mimic the actions. Over time, students begin speaking by giving their own commands. The goal is to reduce anxiety and make learning enjoyable through physical engagement with the language.
This document discusses learning styles and strategies. It begins by outlining the objectives and sequence of topics to be presented. These include how people learn through visual, auditory and tactile means. It then provides background on learning styles and strategies based on the work of psychologists Jung and Piaget. Key definitions are given for learning styles as natural habitual preferences for absorbing information and strategies as characteristics teachers stimulate in students. The importance of understanding learning styles for diverse classrooms is highlighted. Various types of learning styles are then described, including cognitive, sensory and personality styles. Finally, principles for teaching different styles and strategies are outlined.
This document outlines the four main learning styles identified in Kolb's learning styles theory: activist, reflector, theorist, and pragmatist. The activist learns by doing activities like brainstorming and role-playing. The reflector learns by observing and thinking, preferring activities like questionnaires and feedback. The theorist learns by understanding theories behind actions through models and stories. The pragmatist learns by applying ideas in real-world practice through case studies and problem-solving. The document provides strengths and weaknesses of each style.
Leveraging Your Learning Style & Effective Study Strategies
Do you know how you learn best?
Your learning style is the way you prefer to learn. It doesn't have anything to do with how intelligent you are or what skills you have learned. It has to do with how your brain works most efficiently to learn new information. This workshop will focus on helping you identify your own learning style and show you how to develop learning strategies that work for you so you can create a customized approach to achieving academic success.
Total Physical Response (TPR) is a language teaching method developed by Dr. James Asher based on his observations of how children acquire their first language. TPR teaches language through physical actions in response to verbal commands. Students listen and then perform actions commanded by the instructor in the target language without having to vocally respond themselves. TPR is often used with beginners and young learners to develop listening comprehension and vocabulary through coordinated speech and movement before introducing speaking.
The document discusses the Total Physical Response (TPR) language teaching method developed by Dr. James Asher in the 1970s. TPR uses physical movement and actions in response to verbal commands to help lower students' stress levels and increase comprehension when learning a new language. It places emphasis on listening skills before speaking. The method focuses on meaning over form and uses activities like imperative drills, role playing, and materials like pictures. TPR is best suited for basic language acquisition in beginner students through a stress-free environment.
The document discusses different learning styles, including the visual learning style. It describes the VAK model which categorizes learners as visual, auditory, or kinesthetic based on how they receive and process information. Visual learners tend to observe things like pictures, demonstrations, and films in order to improve their knowledge. They understand written instructions better than oral ones and use highlighting, color coding, mind maps and other visual techniques to memorize information.
This document discusses learning styles and how understanding your own learning style can help you learn more effectively. There are three main learning styles: visual, which involves seeing and reading; auditory, which involves listening and talking; and kinesthetic/tactile, which involves hands-on activities. The document provides examples of how each type prefers to learn and techniques to help with learning for each style, such as using pictures for visual learners or discussing material aloud for auditory learners. Understanding your dominant learning style can improve productivity, achievement, problem solving and learning overall.
Рассматривается метод отдельных тел (метод А. Ф. Верещагина) для построения уравнений движения систем тел со структурой дерева. Приводится пример программы моделирования движения цепи n тел на языке MATLAB.
Учебная компьютерная модель «сложение взаимно перпендикулярных колебаний» 200...Павел Ермолович
Целью данной работы является создание в рамках разработанного физического практикума обучающей программы и моделирование основных процессов колебательных движений .
Для реализации указанной цели необходимо было, на данном этапе, решить ряд задач:
Изучить процессы формирования фигур Лиссажу и выполнить расчеты для различных частотных и амплитудных параметров.
Сложение сложных взаимоперпендикулярных колебаний с различными частотами.
Освоить методику формирования и определения параметров фигур Лиссажу.
Создать программу для наблюдения и исследования фигур Лиссажу.
Найти перспективное применение данной тематики на практике.
Обзор работ 7-ой Европейской конференции по космическому мусору (офис центра управления полетами ЕКА, Дармштадт, Германия, 18-21 апреля 2017 г)
Презентация к семинару кафедры теоретической механики Самарского университета (16.05.17)
Основы языка Питон: функции, элементы функционального программирования, списочные выражения, генераторы. Презентация к лекции курса "Технологии и языки программирования".
The document analyzes the chaotic motions that can occur for tethered satellite systems with low thrust. It describes the system and assumptions, presents the motion equations, and identifies stationary solutions. Orbital eccentricity and out-of-plane oscillations are shown to induce chaos if they cause an unstable equilibrium condition. The choice of thrust level, satellite masses, and tether length must satisfy conditions to ensure regular in-plane motion even in an elliptic orbit.
The document proposes using an Autonomous Docking Module (ADM) attached to a space tug by tether to remove orbital debris. The ADM would use a probe-cone mechanism to dock with the target debris, a spent orbital stage, without its cooperation. A mathematical model is developed to simulate the docking process between the ADM and tumbling target. Further simulation and development of rendezvous scenarios and a testbed mission are recommended to validate the concept.
The document discusses nanosatellite deployers, which isolate CubeSats from the launch vehicle and main payload and deploy them into orbit. It describes several common deployer types, including the P-POD, ISI-POD, X-POD, NANORACKS, RSC-POD, and CSD. The document summarizes simulations and experiments that analyzed factors affecting CubeSats' tip-off rates after deployment, such as their mass properties, spring stroke distances, and clearances between guide rails. Ground and microgravity flight tests indicated 3U CubeSats typically have maximum rotational rates under 10°/s after deployment, while 1U CubeSats' rates
The document discusses models and experiments to analyze the tip-off rate dynamics of CubeSats during separation from deployers. A simplified model and complex ADAMS model were developed to simulate the effects of parameters like center of mass position, spring stroke, and gap between guide rails on tip-off rate. Ground experiments using laser sensors to measure angular velocities of a 3U CubeSat mock-up showed results that agreed satisfactorily with simulations. The models and experiments allow estimating tip-off rates to help design CubeSat deployers that minimize initial angular velocities.
The document describes the chaotic behavior that can occur in a system consisting of a space tug, viscoelastic tether, and space debris. A mathematical model is developed to describe the transverse and longitudinal oscillations of the tether. The model shows that chaos is possible when the longitudinal oscillations are perturbed. Poincare sections are used to reveal a stochastic layer in the system's motion due to damping in the tether. The results suggest that chaos can be observed in the attitude motion of the tethered tug-debris system caused by longitudinal oscillations of the viscoelastic tether.
Презентация для IV Всероссийской научно-технической
конференции "Актуальные проблемы ракетно-космической техники» ("IV Козловские чтения")". г. Самара, 14-17 сентября 2015 г.
The document discusses active debris removal in space using tethered towing. The authors have developed a mathematical model of the attitude motion of a debris-tether-tug system. The model accounts for factors such as flexible appendages on the debris, fuel residuals, tether properties, and environmental forces. The authors aim to further study the capture dynamics of debris and stabilization after capture, and create a comprehensive model covering all stages from initial capture to atmospheric reentry.
Исследование движения космического лифта при подъёме груза на орбиту
1. Исследование движения космического
лифта при подъёме груза на орбиту
Кафедра теоретической механики
Пикалов Руслан Сергеевич
pickalovrs@gmail.com
Руководитель: к.т.н., доцент Ледков Александр Сергеевич
ledkov@inbox.ru
Самарский государственный аэрокосмический университет
имени академика С. П. Королёва
(национальный исследовательский университет)
21 июня 2013 г.
2. Идея космического лифта
Космический лифт - механическая
система предназначеная для подьема
и спуска грузов на орбиту
Основные состовляющие КЛ:
Трос
Противовес
Подъёмник
Цель: исследовать динамику КЛ
при подъёме груза на орбиту
(Кафедра ТМ СГАУ) 2 / 26
3. Задачи и допущения
Задачи:
Построить математическую модель КЛ
Исследовать динамику КЛ с учетом движения
подъёмника
Допущения:
Трос - однородный тонкий стержень
Противовес материальная точка
Гравитационное поле потенциальное
Вращение Земли равномерное
Влияние атмосферы не учитывается
(Кафедра ТМ СГАУ) 3 / 26
5. Обобщеные координаты
q1 = ϕ - угол отклонения от экваториальной плоскости
q2 = ψ - угол отклонения от плоскости OXZ
q3 = r - длина троса
q4 = x - растояние от точки закрепления до подъёмника
(Кафедра ТМ СГАУ) 5 / 26
6. Лагранжиан механической системы
Лагранжиан системы:
L = T − P.
T = Tpr + TC + TL. (1)
Кинетическая энергия противовеса:
Tpr =
1
2
mprV 2
pr. (2)
Кинетическая энергия троса:
TC =
1
2
ω||J||ωT
+
1
2
mCV 2
C . (3)
(Кафедра ТМ СГАУ) 6 / 26
7. Компоненты вектора угловой скорости центра масс троса
ω =
˙ψ sin ϕ
− ˙ϕ
˙ψ cos ϕ
.
J =
0 0 0
0 mC r2
2
0
0 0 mC r2
2
- тензор инерции.
Кинетическая энергия подъёмника
TL = 2 ·
1
2
Jd
˙x2
R2
d
+ 2 ·
1
2
mdV 2
L +
1
2
mgrV 2
L . (4)
(Кафедра ТМ СГАУ) 7 / 26
8. Потенциальная энергия
Потенциальная энергия системы:
P = Ppr + PL + PC. (5)
Ppr = −
µmpr
Rpr
- потенциальная энергия противовеса. (6)
PL = −
µmL
RL
- потенциальная энергия подъёмника. (7)
PC = −
µmC
RC
+
3µj cos2
(γ)
2R3
C/8
+
c
2
(r − lo)2
- энергия троса, (8)
где j - момент инерции троса.
(Кафедра ТМ СГАУ) 8 / 26
9. Выбор закона управления подъёмом
Рассмотрим силы, действующие на подъёмник:
FT =
µmL
R2
L
- сила тяжести
Φe
L = −mLRL cos φ1ω2
E - центробежная сила инерции
ΦC = −2mL (ωE × VL) - сила инерции Кориолиса
(Кафедра ТМ СГАУ) 9 / 26
10. Выбор закона управления подъёмом
Зададим силу в виде
F = Fтяж + Φe
L. (9)
Дополнительная управляемая сила:
Fu1 =
−Φe
L +
mгр
10
t ≤ 150c;
0 t > 150c.
, если sin( t
100
) ≥ 0;
Φe
L, если sin( t
100
) < 0.
(10)
Закон управления подъёмом:
Fu =
F + Fu1 t ≤ 600350c,
F t > 600350c.
(11)
(Кафедра ТМ СГАУ) 10 / 26
12. Параметры космического лифта
mC 5000 кг
mpr 3000 кг
mL 110 кг
md 5 кг
mgr 100 кг
mп 4, 385 · 10−5
кг/м
l0 114 · 106
м
E 630 · 109
Па
S 3, 14 · 1, 5 · 10−4
м2
c E · S/l0
(Кафедра ТМ СГАУ) 12 / 26
13. Сила Fu ≡ 0
Проинтегрируем полученую систему уравнений с начальными
условиями:
ϕ0 = 0, ˙ϕ0 = 0, ψ0 = 0, ˙ψ0 = ωz, r0 = l0,
˙r0 = 0, ˙x0 = 0,
для высот расположения подьёмника
x0 = 46 · 106
м и x0 = 26 · 106
м.
Время t = 0..3600 с.
(Кафедра ТМ СГАУ) 13 / 26
14. График изменения координаты x
Изменение координаты x
для высоты x = 26 · 106
м
Изменение координаты x
для высоты x = 46 · 106
м
(Кафедра ТМ СГАУ) 14 / 26
15. График изменения координаты ψ
Изменение координаты ψ
для высоты x = 26 · 106
м
Изменение координаты ψ
для высоты x = 46 · 106
м
(Кафедра ТМ СГАУ) 15 / 26
16. График изменения длины троса
Изменение длины троса ∆r
для высоты x = 26 · 106
м
Изменение длины троса ∆r
для высоты x = 46 · 106
м
(Кафедра ТМ СГАУ) 16 / 26
17. Движение с учётом подъемной силы
Проинтегрируем уравнения движения с начальными
условиями
ϕ0 = 0, ˙ϕ0 = 0, ψ0 = 0, ˙ψ0 = ωz, r0 = l0,
˙r0 = 0, x0 = 0.
Рассмотрим два случая:
1 Fu1 ≡ 0, начальная скорость подъёмника ˙x0 = 33 м/с;
2 Действует сила (11), начальная скорость подъёмника
˙x0 = 0.
(Кафедра ТМ СГАУ) 17 / 26
18. Подъём груза на орбиту Fu1 ≡ 0
Графики изменения координат x и ˙x при подъёме груза
Координата x Скорость ˙x
(Кафедра ТМ СГАУ) 18 / 26
19. Подъём груза на орбиту Fu1 ≡ 0
Графики изменения координаты ψ и ∆r при подъёме груза
Координата ψ Изменение длины троса ∆r
(Кафедра ТМ СГАУ) 19 / 26
20. Подъём груза на орбиту с учетом силы (11)
График изменения координаты x при подъёме груза
Координата x
x на интервале времени
от 599000 до 601000 секунд
(Кафедра ТМ СГАУ) 20 / 26
21. Подъём груза на орбиту с учетом силы (11)
График изменения скорости ˙x при подъёме груза
Скорость ˙x
˙x на интервале
времени от 0 до 2000 секунд
(Кафедра ТМ СГАУ) 21 / 26
22. Подъём груза на орбиту с учетом силы (11)
График изменения координаты ψ и ∆x при подъёме груза
Координата ψ Изменение длины троса ∆r
(Кафедра ТМ СГАУ) 22 / 26
23. Анимация
(Title for the video)
Подъём груза когда Fu1 ≡ 0
(Title for the video)
Подъём груза при действии
силы (11)
(Кафедра ТМ СГАУ) 23 / 26
25. Использованная литература
1 Асланов, В.С., Ледков, А.С., Стратилатов, Н.Р, Пространственное
движение космической тросовой системы, предназначенной для
доставки груза на Землю, Полет,№2, 2007, с.28-33.
2 Aslanov V. S. and. Ledkov A. S Dynamics of the Tethered Satellite
Systems, Woodhead Publishing Limited, Cambridge, UK, (2012) 320
pages.
3 Vladimir S. Aslanov, Alexander S. Ledkov, Arun K. Misra, and Anna D.
Guerman "Dynamics of Space Elevator After Tether Rupture,"AIAA
Journal, 2013, pp. 1-7. doi: http://arc.aiaa.org/doi/abs/10.2514/1.59378
4 Vladimir S. Aslanov, Alexander S. Ledkov, Arun K. Misra, and Anna D.
Guerman "Motion of the space elevator after the ribbon rupture"//63rd
International Astronautical Congress, 1-5 October 2012, Naples, Italy,
IAC-12,D4,3,9,x13567, p.1-8.
5 Pearson, J., The Orbital Tower: A Spacecraft Launcher Using the
Earth’s Rotating Energy, Acta Astronautica, №2, 1975, pp/785-799.
(Кафедра ТМ СГАУ) 25 / 26