CS 102B Robot Design Thursday, 92304

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CS 102B Robot DesignThursday, 9/23/04

• Todays Class
• Saving and Submitting Lego Mindstorms Programs
• Review of Roverbot Lab and Challenges
• Reading
• Ferrari pp. 98-100
• Erwin Chap. 6, pp. 69-82 Discussion of
  programming touch sensors, line following in NQC
  code (version 1.5)
• Assignments
• Double bumpers today!
• Roverbot file submissions due Friday, 9/24 by
  NOON
• Graded only on submission of (nonempty) program,
  not on content!
• Project 3 SumoBots!

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Saving and submitting Lego Mindstorm programs

• 1. Write your program in Lego Mindstorms.
• Decide on a name no extension. E.g, MyProg, not
  MyProg.ext
• 2. Save it to a drive (not a subfolder)
• A for a floppy drive
• C for the computer hard drive
• WARNING C-drive erased when machine is rebooted!
• 3. Copy it to other folders
• The CS102b Submit Folder (in \\Datastor\mcs1)
• Your own folder in \\Datastor\Students
• You can also email it to me (as an attachment) to
  submit.

3
Roverbot Challenge 1
4

• ROVERBOT CHALLENGE 2
• 1. Zig-zag forwards
• 2. When obstacle hit, beep and go backward for 1
  second.
• 3.Turn right when the left bumper is pressed.
• 4. Turn left when the right bumper is pressed.
• 5. Zig-zag forward again.

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ROVERBOT CHALLENGE 3
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Basics of Programming Languages

• Any programming language has
• Task commands
• Input/Output, calculation
• Decision Structures (If-then, yes-no)
• Statements that let you choose between two or
  more groups of statements
• Repetition Structures (Repeat, For, While)
• Statements that let you repeat a group of
  statements
• Most modern programming languages have
• Subprograms (Subroutines, functions)
• Let you give a name to a whole set of statements
  to create a new single, complex statement
• Some modern programming languages have
• Parallel processing (Concurrency)
• Perform two or more sets of tasks at the same time

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Lego RCX Code Programming

• Program block
• Top block to begin every RCX Program
• Small blocks (green)
• Task commands, such as input, output,
  calculations
• Wait Blocks (Red) and Repeat Blocks (Orange)
• Repetition commands
• Yes or No blocks (yellow)
• Decision commands
• Big blocks and My blocks
• Subprograms
• Sensor Blocks (blue)
• Task blocks (Input)
• Can run sequentially or concurrently

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A Small Block Solution to the line-following
challenge
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Small Blocks

• Power
• Turn motors on or off
• Set power level (1-8)
• Set or reverse direction
• Sound
• Beep (6 choices)
• Tone (choose frequency)
• Comm(unication)
• Send or Clear IR message
• Display variable value
• Display clock

• Variable
• Do arithmetic operations
• Reset
• Reset light or timer
• Advanced

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Sensor Blocks

• Sensors that get outside information
• Touch sensor
• Light sensor
• IR sensor
• Others not part of standard kit Rotation,
  temperature, humidity, etc.
• Sensors that get internal information
• Timer sensor
• Variable sensor
• Sensor blocks attach to the main program block
  and operate concurrently to commands under the
  main program block

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Repetition Blocks

• Repeat blocks
• Repeat a set number of times, forever, while some
  condition is true, until some condition is true
• Condition is value of internal or external
  sensor.
• Wait blocks
• These make the RCX do nothing until some
  condition is true

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Decision block

• Yes or No Block
• Chooses between two options depending on whether
  a condition is true or false
• How could we choose between 3 options? 4 options?