Ch1 - Satellite
Outer space is hard to explore, and studying it is a real challenge for scientists. The conditions and distances in space require using completely different methods of exploration that the ones we use on Earth.
The altitude of 100 km (62 miles) above Earth is conventionally used as the beginning of outer space.
Space probes are robotics spacecrafts that gather the most information about outer space. They are equipped with scientific apparatus such as cameras, devices for measuring the magnetic field, spectrometers or radiation counters. Space probes can also collects samples from space objects they visit.
Space probes can be divided into manned and unmanned ones. Unmanned flights are cheaper and don’t put people in danger. Unmanned space probes have so far managed to explore many places in the outer space – they have reached all the planets of Solar System, several planetoids and some of them have even left Solar System and are on their way to reach other stars of our galaxy.
Manned flights are, on the other hand, a great event for the mankind – they expand the boundaries within our reach.
Apart from their research function, space probes are also important commercially. They are placed in Earth orbit, where they serve as artificial satellites. They support GPS system, ensure communication and transmission of the radio and TV signals. The first ever TV feed that relied on TV satellites took place in 1962.
At the moment, there are about 560 active artificial satellites orbiting Earth.
Artificial satellites are also used in meteorology, which is a scientific study of how atmospheric processes influence weather conditions.
Artificial satellites are placed in orbit by space crafts, also known as space shuttles. Space shuttles can be used multiple times, therefore lowering the costs of both manned and unmanned space flights.
Space shuttles look a bit like planes and, just like planes, they have to land on a runway in a special airport for space flights called a spaceport. Because of this resemblance, space shuttles are sometimes also called “space-planes”.
Launching a space shuttle is complicated and requires either a rocket booster or an orbiter to carry the shuttle upwards.
Build
To build this construction, you will need LEGO Education WeDo
Explore
This construction represents a satellite and a space shuttle.
It consists of a rotating stand and two models installed on top.
The stand rotates because of the motor and two transmissions.
The model has three electronic elements.
1. The hub allows to connect the model with the computer and program it.
2. The motor turns the stand.
3. The motion sensor allows to adjust the rotation speed. The program deciphers information from the sensor and converts it to motor power.
1. Artificial satellite is a device purposely placed in orbit. It can communicate with Earth thanks to the antenna (gear, in this case).
2. Space shuttles are specialized vehicles that, among others, transport satellites and telescopes into orbit.
When flying in space, the shuttle is turned rearwards to protect its delicate front from colliding with space debris.
At present, there is a lot of artificial satellites in space. Most of them help us with communication and take pictures of the planet.
1. Satellites must have expandable and regulated solar cells, which transform solar energy (light) into electric energy.
1. The stand is created with three beams. It's quite tall – after all, the model demonstrates the satellites up high in the orbit.
On top of the stand, you can see two bricks with axle holes – they hold the satellite models in place.
1. The model relies on the turntable mechanism. Rotating is possible because of the transmission below, which is propelled by the motor.
1. This is how the model looks like when operating.
1. The transmissions animating the satellite are placed in a firm case. The hub and the motor are connected to it, so the entire model is well balanced and does not move when operating.
This is how the transmissions used in the model look like.
1. This axle is propelled by the motor. You can see a worm installed on it.
2. The worm propels the wheel with 24 teeth. Therefore, the first transmission has 1:24 ratio and transfers the power from the motor to the vertical axle. It means that this axle rotates 24 times slower than the motor head.
3. On this axle you can see a wheel with 20 teeth, meshed with a wheel with 12 teeth. This is another transmission, but an accelerating one with ratio 20:12.
4. Thanks to both of these transmissions, the stand is in the middle of the case.
Program
The program for the Satellite robot will set it in motion and will allow you to control the rotation speed by using the motion sensor.
