TETRIX ROBOTC Online Professional Development Classes will begin at 6:00pm EDT

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TETRIX ROBOTCOnline Professional
DevelopmentClasses will begin at 600pm EDT
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Welcome

• Welcome
• Review Forum Posts
• Technical Difficulties?
• Homework Review
• This Week
• Basic Movement
• Advanced Movement

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Homework Review

• Forum Post
• Most of you have posted good job!
• Anyone who forgot can still post and receive full
  credit.
• Building the Robot
• Everyone build REM bot?
• Okay if you didn't
• TETRIX Robot?
• Wasnt required for today.
• We'll do more with this Wednesday and Thursday.

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Planning and Behaviors

• What is the role of the programmer?
• How does the connection between Human and
  Programmer work?
• Humans Create Plans
• Robots Follow out Plans (exactly as told)
• Sometimes a little too well...

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Planning and Behaviors

• What is the best method to create a plan?
• Behavior based planning
• Each behavior then breaks down into multiple
  "steps"
• Each "step" usually correlates to a single line
  of code in ROBOTC
• Give an example of a daily activity and the
  behaviors involved
• Hint Think about the quizzes you reviewed

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ROBOTC Rules/Syntax

• What does every program have to have?
• task main()
• Set of "Curly Braces
• In what order does ROBOTC run a program?
• Sequentially Top to Bottom
• What is whitespace?
• Space in a program to make it easier for a human
  to read.
• Simple Robot Commands (statements) always end
  with a?
• Semicolon

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ROBOTC Rules/Syntax

• Paired Punctuation
• Some functions have "square brackets , other
  have "parenthesis ()
• How do I keep them straight?
• Memorization
• Functions Library
• Control Structures
• Just like task main, they have a set of curly
  braces defining their beginning and end.
• Example?
• Comments
• //Necessary Evil
• Get into the habit now, or you won't do it ever
• Your students learn their habits from you

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ROBOTC Rules/Syntax

• Syntax is the cause of 80 of programming errors
• Most important thing to do when troubleshooting
  Check Syntax
• Missing Semicolons
• Incorrect Braces on Structures
• Misspelled words
• Improper case motor vs. MoToR
• ROBOTC is friendly about most of these errors...
  but cant catch everything.

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This Week

• ROBOTC Curriculum
• Movement Section
• Basic Movement
• Speed and Direction
• Improved Movement
• Screen Share ROBOTC Curriculum
• Open the Curriculum
• Head to the Movement Section
• Head to the Moving Forward Chapter

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First Program - "Moving Forward"

• Screen Share ROBOTC Application
• Code Breakdown
• Code Modification
• ROBOTCs Compiler
• Downloading a program to the NXT
• Quick intro to the ROBOTC Debugger

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Self Paced Lab Speed Direction

• Follow along with the videos!
• Watch the two videos in the "Speed and Direction"
  chapter of the Movement section.
• Put a checkmark in your box when you have
  finished.
• If finished early
• Review the Speed and Direction quiz
• See if you can answer the questions
• Recommended Time 15 minutes

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Speed and Direction

• Any Questions?
• Notes
• Motor speeds are always between -100 and 100
• Giving a motor a speed above 100 will not break
  anything, ROBOTC will just ignore it and set the
  speed to 100.
• Motors may have difficulty moving at speeds
  between -5 and 5
• This is because of internal resistance from the
  gears inside the NXTs motor

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Differentiated Instruction

• Everyone learns different things at different
  paces
• Everyone MUST move at a different pace
• Going too fast results in failure and frustration
• Going too slow results in loss of attention (i.e.
  future failure)
• The ROBOTC Curriculum software is a teaching aid
  to help with this
• One instructor cant teach at 20 different paces
  simultaneously
• One instructor plus 20 computers can

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Robo 500 Challenge

• Grab a "Large Book"
• Complete the "Robo 500 Challenge"
• Using the book is easier than trying to use
  electrical tape to make a line.
• Put a checkmark in your box when you have
  finished
• If finished early
• Make sure your code is commented
• Try to make the robot turn around and complete
  the Robo500 in reverse.
• Recommended Time 20 minutes

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Robo 500 Challenge

• Group Share
• Code Analysis of "Robo 500"
• How did you solve it?
• Screen sharing is available/recommended

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Robot Functionality

• wait1Msec(2000)
• Timing isn't everything
• Limited to Battery Power
• Surface and Traction of the wheel
• There has to be a better way!
• The NXT motor has one really nice feature

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NXT Motors

• Semi-powerful DC motors
• Equipped with Encoders
• Can measure the distance traveled
• Returns 360 "counts" per revolution
• What else has 360 counts?
• NXT Encoders also enable us to "control" the
  speed of our motors
• PID Algorithms
• Its okay if you dont know what that is yet.

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Self Paced Lab Improved Movement

• Follow along with the videos!
• Watch 3 videos videos in "Improved movement"
• Skip "Synchronized Motors"
• Put a checkmark in your box when you have
  finished
• If finished early
• Head to Wikipedia and read more about PID
  Algorithms
• http//en.wikipedia.org/wiki/PID_controller
• Recommended Time 20 minutes

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Review Improved Movement

• Any Questions?
• Notes
• PID Useful for regulating speed
• Target Distances Useful for making a motor
  travel a specific distance
• PID is on by default for NXT motors
• PID doesnt work very well at high speeds
• Theres no room for the motor to compensate for
  resistance.

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Encoder Targets
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NXT vs. TETRIX

• So, cool stuff we just learned... what works with
  TETRIX?
• PID Kinda
• nMotorEncoderTarget - Kinda...
• The TETRIX motors do not have encoders built
  into the motor.
• 79.95 from Pitsco (each!)
• Not required for class, but recommended for
  general TETRIX use.

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Homework

• Assignment 1 Modify Robo500
• Change the wait1Msec() to use Encoder Targets
• Submit your code as a new topic on the forums
• Extra Credit Submit a picture or video of your
  robot completing the Robo500.
• Assignment 2 Provide Feedback
• Find someone elses modified ROBO500 code and
  provide feedback to that student via the forum.
• Multiple people can comment on the same students
  work, but the idea is that everyone will get at
  least some feedback from other students.
• Assignment 3 Troubleshooting Worksheet
• Complete the worksheet posted on the forums under
  the Tuesday forum.
• Post your answers as a reply to the worksheets
  thread.
• Assignment 4 Finish Building Mantis (optional)
• Build the Mantis Robot
• Building Instructions are available under the
  Setup TETRIX in the ROBOTC Curriculum

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Closing Thoughts

• Class activity Speed and Direction
• Teacher concept Student-paced Instruction
• Challenge Robo 500 (version 1)
• Robot concept Using timing to complete a task
• Class activity Improved Movement
• Hardware Concept Using encoders feedback

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Open Lab QA

• Any questions or discussions?
• Feel free to work on your Robo500 (rev 2)
  assignment.
• Ill be here until 100pm Eastern to answer any
  questions or provide assistance.