After the presentations:

AM: Don't forget to bring the DDR pads and the game + memory card. I think Abraham will supply the PS2.
I'll bring 2 GC controllers if Matthew's bring his GC.

PM: I dunno if anyone's bringing anything, but we could HALO if someone brings their Xbox and 4 controllers or anything else.

3rd week guys, we're almost halfway through!

Today: July 3rd

1. Exam Review
2. Exam (Wasn't that fun...?)
3. Steering systems lecture
4. Slalom Robot (no, its not impossible)

Homework:
Work on Slalom Robot

For those who were confused during the lecture, here's something that might clear it up:

Lego has a few basic building blocks:

Bricks (as seen in pictures 1 and 2)
Plates (picture 3)
Beams (4 and 5)

There are also pegs, which are the black and grey cylinders used to connect beams together. The black pegs are slightly bigger and therefore are not free to spin while inside beams, unlike grey pegs which are free to spin.

Standard lego measurements are 5*5*6 (as seen in picture 1). "5*5*6" is just units of lego; it isn't a real measurement. You can easily find the dimensions of other bricks simply by counting the studs (the bumps on the bricks). Each stud will count as 5, and each brick is always 6 tall. Plates are counted the same, except each plate is 2 tall. Three plates make up the height of a brick.

You can use Pythagorean theorem to perfectly calculate bracing on a row of beams, if you want to. (more on this tomorrow)

The other important part of legos are the gears. You should be familiar with the three gears you'll be using the most:

8 tooth gear
24 tooth gear
40 tooth gear

When you connect gears together, you alter the torque and angular velocity. Your motor spins at the same angular velocity no matter what. In other words it has a constant RPM (unless you change power levels). This means that your motor will spin each gear at equal angular velocity.

What happens if you connect an 8 tooth gear, which is connected to the motor, to a 24 tooth gear?

For every revolution of the 8 tooth gear, the 24 tooth gear only goes through 8 teeth, which is exactly 1/3 of the whole gear. That means for every three times the 8 tooth gear does a revolution, the 24 tooth gear does one revolution.

This will result in the final angular velocity being SLOWER, since it takes more turns to spin the gear around. It is 3 times slower. However, your torque is multiplied 3x; this gearing setup would be advantageous if you were climbing some kind of incline.

Gears can also be combined in more complex ways, as seen in diagrams 6 and 7. If you have questions on this, ask on the discussion forum.

Another important gear configuration to know is in diagram 8, with a 40t connected to a 24t connected to a 8t gear. Suppose the motor is connected to the 8t. What is the final gear reduction?

As it turns out, you can calculate the gear reductions separately and just multiply. The 8t connected to the 24t gives:

8/24

and the 24t connected to the 40t gives:

24/40

If you multiply these two together, you get 8/40, or one fifth. This is the same gear reduction as if you just had the 8t and 40t gears.

The center gear is called the IDLER gear, because it does not affect gearing. It does, however, reverse the direction of the whole gear setup.

Last thing about gears is the clutch gear. The clutch gear limits the amount of torque that can pass through. This is useful for avoiding damage to your robots. When the motors stall (they are on but unable to spin the wheels due to some kind of obstruction) the clutch gear will allow the motor to spin and avoid damage.

In this class there will be many group projects that you and two other students will undertake. Each of these group projects will require a written Project Report. You and your two group members are responsible for turning in a Project Report on your robot.

Project Manager: The Project Manager has to make sure everyone knows what they’re doing. The Project Manager also has to keep track of any difficulties the group encounters, either in building or programming or designing, and how that problem was solved.

Chief Engineer: The Chief Engineer is responsible for construction and development of the project as per Project Manager’s specifications. The Chief Engineer must provide a more detailed drawing and description of the final product in the Project Report.

Head Programmer: The Head Programmer creates and writes the program code for the robot as per Project Manager’s specifications. The Head Programmer must include a translation into words of the ROBOLAB code in the Project Report.

The Project Report must include the following:

1) The Project Manager’s initial plans with:
a. A cover page with partners’ names and titles, and the robot name.
b. A description of what the robot is supposed to do.
c. An outline of the problems encountered, and how they were solved. This is the most important part of the report. You won’t be graded on what you found difficult, but rather how you solved the problem. There should be at least three problems, one paragraph per problem.

2) The Chief Engineer’s final plans with:
a. A well developed drawing of the robot that could be interpreted by another group.
b. A description of the key parts of the robot.

3) The Head Programmer’s final code with:
a. An English translation of the ROBOLAB code.
b. A summary of how and why the program works.

If you work with the same people every time, make sure you rotate roles so that everyone has a chance to try out each job.

Erm...I like how three of my past posts just got erased for no apparent reason...
That includes the Group Guidelines, Assignment 1, and the first day.
I'll try to type it up again later when I get the documents again.

For now, I'll just retype the most important piece of information out of the three:

Corey Lab:
RECORD TEMPERATURE:

85 Degress F - 6-22-06

This is the introduction letter that Mr. Liao passed out during the orientation.

Dear Parents and Students,

Welcome to Robotics. Over the next six weeks we will be exploring the broad field of robotics, and also touching on concepts of physics, engineering, programming, and artificial intelligence. Through building different robots, studnets will gain an appreciation for all the different sciences that fall under robotics.

My name is Abraham Liao and I am the instructor for this course. i am currently a student at UC Berkeley studying Electrical Engineering and Computer Science. I have worked with ATDP for many years mentoring and being a teacher's assistant. This is my first year teaching this course, though I have been a teacher's assistant for this course twice. I look forward to teaching this course.

The robots students will build will range from those capable of very simple tasks, such as following a line, to much more complex, nearly intelligent robots capable of maneuvering a room with obstacles. These will be similar to robots you might have seen in various robot competitions. The use of Legos allows students to quickly modify robots without the use of a welding torch or soldering iron. The ROBOLAB programming language is very intuitive and allows students to easily program robots for anything they can imagine.

Students should expect to have five to ten hours of homeworks each week. Robot kits will be kept in class during the week, and taken home over the weekend. Homework will generally consist of building assignments and problem sets dealing with topics related to the build. There will usually be two robots in class per week, plus one over the weekend. Homework time will vary depending on the difficulty of each robot. Since there will be group work, students are expected to contact each other outside the class via phone or the internet.

Students need notebook, pencils, and a calculator to keep track of assignments, taking notes, and solving problems. These need to be brought to class daily and taken home afterwards. Students also need to purchase a robotics kit and software, which can be purchased from http://www.legoeducation.com. Students need the Team Challenge Set with USB Cable (Product Code W979794) and ROBOLAB 2.5.4 Software with raining missions (Product Code W900076). The prices are $199 and $69, repectively. If you already have a different set, please let me know.

Class will be held on he UC Berkeley campus in the Corey Computer Lab, located on the first floor of Tolman Hall. The first class will be on June 19th. If you have any questions, feel free to e-mail or call me any time before 11pm.