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Global positioning system (GPS)
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Topical vocabulary:
| navigation | навигация |
| global positioning system | спутниковая навигационная система (GPS) |
| land-based system | наземная станция |
| triangulation | триангуляция |
| pinpoint position | точные координаты |
| mode | частота (для радиосигналов) |
| differential mode | режим работы на разностной частоте |
| time (v) | измерять время; отмечать время; хронометрировать |
| delay | запаздывание |
| radio message | радиосигнал |
| radio wave | радиоволна |
| travel time | время прохождения сигнала |
| figure out | определять, вычислить, рассчитать |
| to generate code | посылать код; команду |
| ranging | определение дальности; измерение расстояния |
| satellite ranging | определение расстояния с помощью спутника |
| to multiply | умножить |
| to synchronize | синхронизировать |
| reference points | опорные точки |
Text
About the middle of the 20th century scientists discovered a way to measure distances using radio signals. A more recent procedure for global positioning relies on satellites whose locations at any instant are known from a series of stations in all parts of the world. GPS (global positioning system) was developed by the US Department of Defense to simplify accurate navigation.
The satellites are high enough that they can avoid the problems encountered by land based systems and they use technology to really give pinpoint positions anywhere in the world 24 hours a day. In actual use people are getting measurement accuracies better than the width of an average street. And in “differential” mode surveyors are using GPS to make measurements down to a centimetre.
The basic principles of GPS are really quite simple. Ignoring some of the details we can break the system into 5 conceptual pieces.
1. The basis of the system is triangulation from satellites.
2. To triangle, GPS measures distance using the travel time of radio message.
3. To measure travel time, GPS needs very accurate clocks.
4. Once you know distance to a satellite, you then need to know where the satellite is in space.
5. As the GPS signal travels through the ionosphere and the earth’s atmosphere, it gets delayed.
GPS is based on satellite ranging. That means that we figure our position on earth by measuring our distance from a group of satellites in space. The satellites act as precise reference points for us (for triangulating our position somewhere on the earth). Position is calculated from distance measurement to satellites.
The GPS system works by timing how long it takes a radio signal to reach us from a satellite and then calculating the distance from that time. Radio waves travel at the speed of light 186,000 miles per second. So we can figure out exactly when the GPS satellite started sending its radio message and when we receive it we’ll know how long it took to reach us. We just multiply that time in seconds by 186,000 miles per second and that is our range to the satellites.
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The big trick to measuring the travel time of the radio signal is to figure out exactly when the signal left satellite. To do that the designers of the GPS system came up with a clever idea: synchronize the satellites and receivers so they are generating the same code at exactly the same time. Then all we have to do is receive the codes from a satellite and then look back and see how long ago receiver generated the same code. The time difference is how long the signal took to get down to us.
Practical work № 5
I Give Russian equivalents of the following:
1) signal travels through the ionosphere;
2) calculating the distance;
3) locations at any instant are known;
4) travel at the speed of light;
5) travel time of radio message;
6) it gets delayed
II Find English equivalents of the following:
1) спутниковая навигационная система;
2) круглосуточно;
3) система наземных станций;
4) точность измерений;
5) производить измерения с точностью до 1см;
6) время прохождения радиосигнала;
7) определение расстояния до спутника;
8) точно рассчитывать.
III Say, whether the statements are true or false:
1) GPS was developed in Russia to simplify accurate navigation.
2) Surveyors using GPS make measurements down to 1m.
3) The basis of GPS is triangulation from satellites.
4) GPS is based on satellite ranging.
5) We can’t say when the satellite starts sending radio signals.
IV Answer the questions:
1) When did the scientists find the way of measuring distances by means of radio signals?
2) Where was GPS developed?
3) What is the GPS measurement accuracy in differential mode?
4) What is the basis of GPS?
5) What does GPS need to measure travel time?
6) How do we locate our position on the earth by GPS?
V Find English equivalents of the following:
1) Способ определения расстояния с помощью радиосигналов был открыт учёными в середине ХХ века.
2) GPS была разработана в министерстве обороны США для точного определения местоположения.
3) В основе GPS лежит триангуляция с помощью спутника.
4) Местоположение на земле определяется измерением расстояния до спутников, которые выполняют роль опорных точек.
5) Спутники и приёмники подают одинаковые сигналы в одно и то же время.
6) Время задержки означает, сколько времени понадобилось, чтобы сигнал достиг нашего местоположения.
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Criteria of marks:
16-21 – “satisfactory”
22-28 – “good”
29-31 – “excellent”
Unit 7
DRONES
Topical vocabulary:
| unmanned aerial vehicle (UAV) | беспилотный летательный аппарат (БЛА), «беспилотник», дрон |
| unmanned aircraft system (UAS) | |
| surveillance | (видео) наблюдение, мониторинг |
| wildfire detection | обнаружение лесных пожаров |
| crop evaluation | оценка урожайности |
| electric power lines | линии электропередач (ЛЭП) |
| spying | шпионаж |
| fuselages | корпус, фюзеляж |
| wingspan | размах крыла |
| quadrocopter | черырёхвинтовой (квадрокоптер) |
| collision | столкновение |
| gimbal | карданная подвеска |
| disaster area | район стихийного бедствия |
| artificial intelligence | искусственный интеллект (разум) |
| to control remotely | управлять удалённо |
| remote driver | удалённый оператор |
Text
Drone is an unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS). Unmanned aircraft dubbed "drones" are now widely used for military purposes, surveillance, environmental monitoring (including wildfire detection, crop evaluation, electric power lines monitoring etc.) and spying for celebrities. Typically, their fuselages are 2 to 3 meters long, and their wingspan is 3 to 4 meters. There are also smaller drones, about half a meter in the longest dimension. A more recent invention is quadrocopter drones.
A team of scientists and engineers at Switzerland at the Ecole Polytechnique Federale de Lausanne has developed a drone of a size of a large insect. Actually, it is much larger, but only because it is encapsulated in a spherical frame of tiny metal rods, which protects it from collisions and crashes. The diameter of the protecting sphere is 34 cm. The drone itself is about 10 cm in its largest dimension. The team called their invention "Gimball" because it looks like a ball and because the drone can rotate in 3 axes within that spherical frame being suspended on gimbals *.
The flying robot can take off from horizontal or vertical surfaces, including tree trunks and walls of buildings. This robotic aircraft can be used in disaster areas, where presence of people may be dangerous, for surveillance, monitoring and evaluation of further possible actions. Its own mass is 370 g, and it can carry additional equipment up to 30 grams. This can be gas sensors, sensors of toxic chemicals, radioactivity sensors. The drone is controlled remotely, it sends video signal to the remote driver. The robot can stabilize its attitude and direction of flight and handle possible collisions with obstacles in case of temporary interruption of communication. Further development of this robot will include incorporation of artificial intelligence to allow it to accomplish certain complex task by itself.
This text is based on the information presented in the BBC popular science radio programmes.
* Карда́нов подве́с — универсальная шарнирная опора, позволяющая закреплённому в ней объекту вращаться одновременно в нескольких плоскостях. Главным свойством карданова подвеса является то, что если в него закрепить вращающееся тело, то оно будет сохранять направление оси вращения независимо от ориентации самого подвеса.
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Practical work № 6
I Translate into Russian:
1) a drone of a size of a large insect;
2) environmental monitoring;
3) stabilize its direction of flight;
4) dubbed "drones";
5) presence of people may be dangerous;
6) carry additional equipment;
7) to accomplish certain complex task;
8) a more recent invention;
9) a drone can rotate in 3 axes;
10) its own mass is …
II Find English equivalents of the following:
1) взлетать с поверхности;
2) для военных целей;
3) оценка возможных дальнейших действий;
4) слежка за знаменитостями;
5) временное отключение связи;
6) избежать возможных столкновений;
7) помещён в рамку;
8) дрон управляется удалённо;
9) внедрение искусственного интеллекта;
10) датчики радиоактивности.
III Answer the questions:
1) What is a drone?
2) How much is the wingspan of a typical drone?
3) In what spheres can the robotic aircraft be used?
4) Why has a new drone got the name of a “gimball”?
5) How much is a diameter of the protecting sphere?
IV Find English equivalents of the following:
1) Группа учёных разработала дрон размером с крупное насекомое.
2) Существуют также небольшие дроны, размером не более полуметра.
3) При удалённом управлении оператору посылается видеосигнал.
4) Роботизированный дрон может взлетать с поверхности ствола дерева или стены здания.
5) Это могут быть датчики газа, токсичности или радиоактивности.
Thank you!
Criteria of marks:
15 –19 -“satisfactory”
20- 26 – “good”
27-30 – “excellent”
Unit 8
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