Braden

March 25, 2011 Log Entry #1 Intro to Electronic Devices

Analog signals are different from digital signals because of the form of the current. Analog signals are usually sent out by TV’s, VCR’s, radios and telephones. They do not jump or have on and off, but they are ups and downs. Digital signal changes in jumps. Devices like CD and DVD’s use digital signals. In electronic devices, it is also important to use semiconductors. Semiconductors are elements that can become very poor conductors of electricity. A semiconductor’s conductivity can also be controlled. They are controlled by adding impurities. Diodes and transistors both allow current to flow only in one direction. Integrated circuits are tiny chips of silicon that can contain millions of diodes and transistors. They help contain data in a very small size. It is important for us to have electric devices on a space mission to Mars for many reasons. The main reason is humans cannot go onto the surface of Mars. We need computers, robots, and technology to use on Mars. Rovers can roam the surface and collect samples and do analyses of the planet. Computers can analyze and record data about samples or data. Without them, we couldn’t graph our data or have video from Mars. Without computers, we couldn’t plan on the launch speed and trajectory for the rover, or where the sun is for the solar panels. We could do nothing on Mars unless we had the technology that we have now. Electronic devices and signals can also help us send information to and from Mars.

//Ms. Mc: Very good overview of electronics and ideas for how we would use electronic devices on our mission to Mars. ICs not only help contain data in a small size they allow electronic devices to be smaller since they include thousands of electronic components in a small area. 9.5/10 //

The History of the Rocket Log Entry #2 4/5/2011

Although the actual release of true rockets is unknown, the first things to use the same principles as rockets have been around since 100. B.C. At first, there was just steam being used to propel a sphere. This showed that steam, and therefor liquids, can be turned to gas, which can propel an object. This was invented by Hero of Alexandria. The Hero Engine moved because of Newton’s 3rd Law. When the Chinese began to use a fireworks, they used gunpowder, and maybe one accidentally propelled itself and did not explode. The Chinese experimented with these gunpowder tubes, then later launched them with bows. Later, they were launched by bamboo. They could propel themselves off of their own power, so they were the first true rockets. The Chinese continued to use rockets, this time as warfare. They would use "arrows of flying fire" or rocket arrows. They were simply a tube open on one side, and capped on the other filled with gunpowder attached to a long stick. The ignition would launch the rocket. The stick provided some control for the direction of the flight. Later, in England, a monk, Roger Bacon, worked with gunpowder in rockets. In France, Jean Froissart discovered that a tube could provide a more accurate launch. Italian Joanes de Fontana designed the surface running rocket-powered torpedo.

More often than not, the words “Modern Astronautics” and “Konstantin Tsiolkovsky” or are mentioned in the same sentence. He was the first person to propose the idea of space exploration by rocket. He suggested that liquid propellant would help a rocket achieve a greater range. In the early 1900's, American Robert H. Goddard began experiment with solid-propellant. After his experiments, he decided that liquid propellant is better than solid propellant. He also achieved the first successful liquid-propellant rocket flight. His rockets became bigger and flew higher. He was known as the "Father of Modern Rocketry". Many years later, war and exploration were the only reasons for rockets. After the creation of NASA, National Aeronautics and Space Administration, the whole world began to learn more about space and rockets. Rockets have now been to the moon and also explored outer space.



//Ms. Mc: Great summary of ancient rocketry and drawings. Please insert your drawings/photos in your text when you discuss them and refer to them (i.e., see Figure #1 below). You left out the contribution of the Russians to modern rocketry, especially the creation of the first satelite, Sputnik. 14/15//

4/5/2011 __Log Entry #3__ __Rocket Flight Stages Simulation__

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4/13/2011 Log Entry #4

 The rocket is comprised of eight main parts, the nose cone, body tube, recovery system, recovery wadding, launch lug, fins, motor mount, and the rocket motor. The nose cone is the cone at the top of the rocket. It is aerodynamic and helps the rocket fly straight through the sky. The body tube is the long and narrow tube that holds the engine and recovery system. It is usually paper. The recovery system is the parachute and other parts that help the rocket to safely land back on the surface. The recovery wadding is the layer that protects the recovery system from catching fire. The launch lug is the small tube that guides the rocket off the launch pad. The fins stick off the sides of the rocket and keep it going straight, but if they aren't symmetrical, the rocket won't go straight. The motor mount is what holds the rocket motor in place so the thrust pushes it straight up and not sideways. The rocket motor is a non-reusable motor that is ignited to propel the rocket upward.

//Ms. Mc: Good explanations of the rocket parts' functions. Oops, you forgot a couple of labels; recovery wadding and fins (-2). Also, if a part was inside the rocket, you were to write the work "inside" in parentheses following the rocket part name but I got what you meant :). Please add a caption for all figures/graphs/tables (-1) and a title for your entry (-1/2). 16.5/20//

4/17/2011 Log Entry #5

The purpose of the experiment was to find out how different masses of rockets affected the apogee of the flight. This was found by making the same rockets with a different mass and launching them with the same conditions. When the rocket was at rest, the force of gravity and the force of the launch pad were acting upon it. They were equal, so the rocket didn’t move. When the rocket blasted off, the force of air resistance and the force of gravity acted upon the rocket, but the thrust of the engines was much stronger. During the powered flight, the force of gravity and air resistance was also less than the thrust of the engine, so the rocket continued to fly upward. During the coasting, the engines stopped, but the rocket continued upwards because of inertia. At the apogee, the force of inertia was overcome by the force of gravity, so the rocket reached the highest point in the flight. It was hypothesized that if the mass of the rocket changed then the apogee would change because of Newton’s Second Law. It says that the greater the mass of an object, more force is required to move it. The lighter rockets should reach a higher apogee because they have less mass. With less mass and the same engines, the powered flight would be less work for the engine, so it could sustain the powered flight stage longer. Once the powered flight was over and cruising began, it would use its small amount of inertia to finish at the maximum height possible. The heavier rockets should have the lowest apogee because they have more mass. With a heavier rocket and the same engines, Newton’s 2nd Law states that the engines would need to apply more force to accelerate the object. Since the rockets cannot apply more or less force, they apply the same amount, so the rocket takes longer to lift-off. Once the powered flight begins, the engines also need more force to keep the heavier rocket going. The rocket wouldn’t go as high during the powered flight stage. Once the coasting begins, the rocket relies on its inertia to stay moving. The rocket has a greater inertia because it is heavier, but it still wouldn’t go as high as the lighter rocket.

The rockets were launched and the apogees were recorded using trigonometry (as seen in **Figure 1)**. When launched, the rockets were measured using an angle gun from exactly 100 meters away. The rockets had masses of 42.5g, 43.2g, 44.0g, 44.5g, 44.6g, 44.8g, and 45.4 g. They were all around 44g with a range of 2.9g. The apogees were 61m, 68m, 84m, 93m, 90m, 85m, and 82m. They had a range of 32m. The relationship was a direct relationship. The outlier would be the heaviest one with the apogee of 82m. The rest seem to follow the direct relationship pattern. The hypothesis was proved to be incorrect. The reason that the hypothesis could have been wrong could be because the wind would affect the lighter rockets more than it affected the heavier ones. Also, once coasting began, the lighter rockets didn’t have as much inertia, so the wind might have affected them more.

Figure 1. The scatter plot of the apogees.

4/26/2011 Log Entry #6

What is a galaxy? How did they form? A galaxy is a system of billions of stars that are held together by gravity, gas, and dust. They are formed by a tiny pinpoint that is unimaginably hot and dense. Then it exploded. Gas and dust collapsed and collided to make clumps. The clumps became stars. They collect gas and dust.

Which is older, the universe or our solar system? Or are they the same age? Explain. The universe is about 14 billion years old, and the solar system is about 5 billion years old. The universe is older because the solar system the solar system was created in the universe much later. <span style="color: black; font-family: 'Adobe Kaiti Std R',serif; font-size: 14pt; margin: 0in;">

//Ms. Mc. Your answers were a little short on detail. When did galaxies first start to form and about what size are they? (-1/2). Your second sentence for your second sentence doesn't make sense (-1). Figure 2 is a spiral galaxy (perhaps the Milky Way) and not our solar system (-1/2). Also, you forgot your title for your entry (-1/2). 7.5/10//

Log Entry #8 5/5/2011 In challenge 1, the robot was supposed to follow a straight line, turn 90% right, follow a straight line, turn 90% left, and reverse down a straight line. Once it stops, it spins around twice, then it plays applause, then it display a smiley face. The 1st block was a motion block. It told the B and C servomotors to go forward 3.65 rotations at 75% speed and stop by braking. This made the robot move forward 61cm. The 2nd block told servomotors B and C to turn right sharply at 75% speed for 175 degrees. This made the robot turn 90 degrees to the right. The 3rd block told the B and C servomotors to go forward 1.827 rotations at 75% speed and stop by breaking. This made the robot go forward 31cm. The 4th block told the B and C servomotors to turn sharply left at 75% speed for 175 degrees. This made the robot turn 90% to the left.The 5th block told the B and C servomotors to reverse at a 95% speed for 1.312 rotations and then stop by braking. This made the robot go forward 22cm. The 6th block told the B and C servomotors to rotate sharply right at 100% speed for 1400 degrees. This made the robot turn 720 degrees. The 7th block told the robot to wait 1 second. The 8th block told the robot to play the Applause sound file at 100% volume. This told the robot to play the applause. The 9th block told the robot to display a smiley face. The 10th block told the robot to wait 1 second until the 11th block closes the smiley face. This is all seen in Figure 1. This could be applied to the Mars mission because if we knew about the physical geography of the surface of Mars, the rover could move around and not get hurt.