Kendall

5/18/10 Post #8
All living things are: Made of cells, need materials, maintain some form of Homeostasis, respond to stimuli, reproduce, grow, adapt and respirate. The fist of the 8 is pretty self explanatory. When something needs materials that means it needs something else to live. Rocks don’t need anything to exist. They are not living. Examples of materials include O2, Water, vitamins and minerals plus any other form of food. Hom means the same in Greek. Stasis is state. So Homeostasis is when something maintains the same state internally despite the environment. This doesn’t necessarily have to be temperature even though that is a good example. Others include blood pressure, food intake etc. Stimulus is anything that causes living things to react. Therefore responding to Stimulus is when the Stimuli stimulate the living thing. Reproduction is the ability to produce another living being of the same kind. Growth is the transition from simplicity in being to complexity. Factors in growth include diet disease and temperature. Adaption is the ability to evolve and suit the way of live. Finally respiration is “releasing the energy stored in the chemical bonds of sugars.” When we breathe we use the O2 to break the bonds.

5/7/10 Post #7
Challenge 1: Driving Course Challenge The challenge was to make the robot run along the tape lines on the floor. The tape was an upside-down “L” shape with a small piece pointing up perpendicular to the top. Then the robot would then go backwards and do doughnuts.

media type="custom" key="6066065"
Figure1: Driving Course Video Figure2: Driving Course Code The first thing you need to know is that the motors are connected to ports B and C. Also the steering window tells how much power will be given to the corresponding port. If one wheel spins faster than the other the robot will turn. If the power is balanced the robot will go straight. The first block is a motion block (all of the blocks are motion blocks as seen in Figure 2) with 100% power balanced 1 rotation (of the wheels). The second and third blocks are the same. The fourth block has 40% power balanced 1 rotation. The next block is a pivot turn. The robot turns but doesn’t move forward. The power is set to 50% and the steering is directing more of the power to the left wheel in order to turn right. The next block is the same as the first block. The sixth block has 20% power balanced 1 rotation. Then we have another pivot turn this time to the left, a 100% power balanced straight 1 rotation, and a reverse block. A reverse block is the same as any other block except in the direction window there is a button with an arrow pointing backwards. This will make the robot move in the opposite direction. The final block tells the robot to do a pivot turn for 1800 degrees or 5 turns. This concludes the program.

5/3/10 History of Robotics
Robots. They are forever changing our lives; sewing our clothes, making our food, doing our work. But what is a robot? According to the Webster a robot is: "An automatic device that performs functions normally ascribed to humans or a machine in the form of a human.” The first robots were in R.U. R. a play written by Czech playwright Karel Capek. The word robot comes from the Czech word for forced labor or serf. But it wasn’t until after WWII when technology exploded onto the world scene. George C. Devol and Joseph F. Engleberger discussed in 1956 how successful they could become by manufacturing robots. Engelberger started the manufacturing company Unimation which stands for universal automation. He has been called the father of robotics. In 1962 the first industrial robot arm the Unimate made by Unimation is introduced. It was designed for work on a General Motors assembly line.



Figure1: Unimation's Robotic Arm Unimate

1977 was an interesting year for robotics. Star Wars came out introducing people to C-3PO and R2-D2 as well as inspiring a whole new generation of scientists and inventors.

Figure2: C-3PO and R2-D2

Also in 1977 Voyagers 1 and 2 were launched into space. In 1981 the robot arm was given motors installed directly into its joints improving accuracy and speed. Skipping forward LEGO Mindstorms 1.0 was released in 1997. Robots are more and more becoming influential on modern society. We have yet to see what will happen next.

Entry #5 Rocket Launch Analysis
The purpose of the experiment was to calculate the highest apogee and find the relationship (or lack thereof) between mass and apogee. When the rocket is on the launch pad gravity is pulling down on the rocket and the normal force is opposing it. At liftoff the thrust has overcome the force of gravity with some air resistance (friction) pulling back at it. Powered flight has the same forces acting on it as liftoff. At coasting gravity is still pulling down but inertia is keeping the rocket moving. Air resistance is still present. It was hypothesized that if the more rocket was more massive then the apogee would be lower because according to Newton’s 2nd law (F=ma) the force of gravity will pull harder on more massive objects. The experiment was preformed as following: 100 meters were measured from the launch pad. Two people were stationed there with angle guns. A five number countdown was given and the rocket was launched. The angle gun bearers measured the angle at which the rocket reached its apogee and the data was averaged and recorded. The same process was repeated for the remaining 8 rockets. Using the angles gathered 100 times the tangent of x angle was taken to find the apogee in meters. A=100tan (B

Figure 1: Graph1: The Relationship between Mass and Apogee

There is an inverse relationship between mass and distance traveled. If something is more massive it will have more inertia to overcome and if the rockets are all propelled by the same engine there will be less powered flight and therefore a lower apogee. Also if something is more massive the force of gravity will pull on it harder. Therefore the rocket will have a greater force to overcome. The hypothesis was confirmed. There were three outliers but there was a general trend. This may be due to human error, weather and/or equipment. The range of the masses was 4.9 grams where as the range of the apogees was 42.3 m. Overall the data showed a downward trend. As the mass increased the apogee decreased.

Rocket parts
== ==

Entry #4 Rocket Parts
The nose cone is the top of the rocket and provides air guidence and aerodynamics. The body tube is the tube that the rocket consists of. It also holds all of the "stuff". The fins direct the rocket and (depending on the type of fin) spin it/keep it straight to improve aerodynamics/make sure it doesn't crash after lift-off. The Launch lug keeps it steady and straight when it is on the launch pad by the means of a pole. The engine is what propells the rocket by burning gunpowder. The engine mount is what secures the engine in the rocket. Finally the recovery system tries to insure a non-eventful landing or recovery.

This Scratch program is simulating a rocket's flight to Mars and the six stages of flight it will have to go through. The Scratch program will start automatically. To stop it click on the stop sign. To reset the rocket press the Space bar. Don't forget to turn on your sound. Enjoy.

4/12/10 It //is// Rocket Science!
In order for a rocket to exist there has to be some kind of propulsion system. A propulsion system is exactly what Hero of Alexandria (I’m assuming that’s a translation) in 100 B.C. when she/he used steam to spin a ball via tubes running up the height. As a kettle with a fire lit under it cannot provide enough thrust to move itself let alone a rocket the next big step was gunpowder which the Chinese invented around 100 AD. It occurred to the Chinese and eventually the Mongols that gunpowder could be used to propelled their arrows independently. Bodies were crafted and the first true rocket was born. Fact: did you know that the bodies of the rockets were often shaped similarly to birds? Here is my interpretation of it from a bird’s eye view:

Figure1: Chinese Rocket Bodies Over the next few centuries improvements were made such as more efficient gunpowder basic guidance systems and Weapons of Mass destruction. But it wasn’t until 1903 when Konstantin Tsiolkovsky a Russian school teacher suggested space exploration and liquid propellants. The seed had been planted for the modern rocket.

But it wasn’t until March 26, 1926 when Robert H. Goddard succeeded in making a liquid propelled rocket that was fully functional. Gyroscopes recovery systems and payload compartments are all achievements under the Belt of the Father of Modern rocketry. From then on rocketry shifted into the fast lane. The Germans developed the V-2 a rocket capable of destroying several city blocks. By the end of WWII rockets could span the Atlantic Ocean. When the German Empire was broken up after WWII many of the German scientists migrated to either the Soviet Union or the US. Both Superpowers realized the rocket’s potential as a weapon and intercontinental weapons were developed. But the next real shock to the world was when the USSR launched Sputnik I into space on October 4 1957. The On January 31, 1958 the US answered with Explorer I.

Figure 2: Explorer I That October the National Aeronautics and Space Administration (NASA) was created. Advanced technology is still being created today. Space has been viewed as an inhabitable place after the Earth becomes uninhabitable. Rockets today can pin-point any location on earth. But we must remember under all of the ceramic and steel, fiber optics and cables, fancy buttons and probing antennae this is what rockets are truly made of. == ==

Summary of Simple Circuitry
Atoms that have electrons in outer orbitals that aren’t full allow electricity to flow. If the energy levels are full then the object is an insulator. Voltage is necessary for electricity to flow. Voltage is the pressure or push that moves the electrons. Voltage is measured in Volts. Current is the flow of electrons and measured in Amperes. Resistance is the resistance of the flow of electricity. Resistance is measured in ohms. Electricity is not intelligent; it is single minded and goes in one direction. The difference in charge pulls/pushes at the electrons. When a circuit is in series all of the electrical components are on one “branch” of wire thus the name series. When a circuit is in parallel the components will be on different branches.

3/24/10
//After reading p. 66-71 of Chapter 3 in Electricity & Magnetism, create the following paragraphs. Paragraph 1 – in first person, explain: 1) how analog signals are different from digital signals, 2) how semiconductors are used in electronic devices, and 3) how diodes and transistors are used. // //Paragraph 2 – In first person, explain where electronics would be useful in a space mission to Mars where the goal is to ultimately search for life on Mars. //

An analog signal is a signal (made from an electronic current) that varies smoothly over time therefore displaying a constant stream of information. A digital signal is a signal also except the information jumps in steps. Semiconductors are metalloids and the building blocks of most modern electronics. Their conductivity can be controlled by doping or adding impurities. If the element added has an abundance of electrons it is an n-type semiconductor and is negatively charged. If the added element has a deficit of electrons it is a p-type semiconductor and is positively charged. Diodes are used to block current flowing in the opposite direction and convert AC to DC. Transistors are used to augment signals in an electronic circuit. They can also be switches. Electronic would be more than useful on our mission to Mars. All transportation would have to be completely electronic as a person cannot survive on Mars. All rovers, cameras, communication and analysis would be electronic. LED lights would be the preferred light source since they are very efficient and bulb replacement would be difficult on Mars. The video and pictures would be digital signals and the sound would be digitized analog signals. Any temperature reading would also be digitized analog signals.