ENGR 100 Robotics Project

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ENGR 100 - Robotics Project
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Presentation Outline

• I. Background Information
• II. Design Project
• III. Engineering (Robot Basics)

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What is a Robot?

• A machine
• Have some IQs
• Can do certain tasks

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Robotics made easy?

• Design Problem -
• Design and build a robot to vacuum your house.

What are some of the challenges?
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Design Challenges for Mobile Robots

• Position
• -How does robot know where it is (or has been
  to)?
• Navigation
• -How does it navigate around obstacles?
• Object recognition
• -How does it recognize money, toys, even cats?
• Power supply
• -How does it avoid running over cord?

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Who Builds Robots?

• ME - designs body, gearing, actuators.
• EE / CSE- software, sensor (designs the
• brain feel), actuators wiring.
• CHEM E / MATL SCI - designs (or selects) power
  supply, materials.
• All engineers listed above work together to
  design/build robots.

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Project Objectives

• The goals of this project are to
• Get excited about Science and Technology.
• Be introduced to basic computer programming.
• Experience the design process.
• Build a programmable robot.
• Learn how robotics involves a multitude of skills
  and knowledge from many subject areas.

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Problem Definition

• To build a computer controlled wheelchair robot
  that can safely deliver an immobile person
  through an obstacle course in the shortest amount
  of time.
• Also, you have to build two other robots to
  perform like a car, and an unfriendly cat/dog on
  the street (The defender).

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Tasks

• Three different tasks
• Robotic Wheelchair, Car, The defender.
• Three different programs
• Program 1 - Robotic Wheelchair (do first!)
• Program 2 - Car
• Program 3 Dog/Cat. The defender (be creative!)

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Obstacle Course Layout
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Scoring for performance grading
10 pts
10 pts
10 pts
10 pts
10 pts
Base Pts At some point before competition day,
each teams robot must complete the entire
course. Additional points each round - 20 pts
for Crosswalk, 20 pts for Car, and 20 pts for
Defender.
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Rules (see handout for complete listing)

• Robotic wheelchairs cannot be touched once
  competition has started.
• Malfunctioning defenders and cars will be removed
  from the course.
• Max robot dimensions at start of competition - 1
  ft x 1 ft x 1 ft
• Wheelchairs and cars sending messages will be
  disqualified. Defenders not limited.

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Project flow

• Know the project goals/requirements.
• Learn RCX programming/Gather ideas for robot
  design.
• Build a pathfinder.
• Test run.
• Final competition.

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This is the competition!
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Robot Basics - Sensors Motors

• Input/Output Ports
• Touch sensors
• Light sensor
• Motors
• RCX signals

Tips - Use view mode to check light sensor.
Battery power affects speed of motors. Batteries
run out fast! Dont block infrared sensor.
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Robot Basics - Gears

• Speed
• Torque (climb over obstacles)
• Turns
• Tips -
• Try different size gear combinations, different
  types of gears (worm), and different motor
  placement (rear wheel drive or 4 wheel drive).

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Robot basics - Control Structures

• No matter what language you use, there are 3
  basic control structures for organizing the
  programming commands
• Sequential
• Repetition (Loops)
• Conditional

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Sequential

• Sequential statements are defined as a list of
  commands that are executed in order.
• For example
• Set Forward Direction
• Go forward for 3 s
• Stop

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Repetition

• Repetition statements allow for a series of
  commands to be repeated for a set number times.
• For example
• Repeat 3 times
• Set forward direction
• Move forward for 3 s
• Stop
• End Repeat

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Conditional

• Conditional statements allow for two (or more)
  different sets of commands to be executed
  depending on a condition.
• For example,
• If certain conditions are true - one set of
  commands will be execute.
• Else if any (or all) are false - another set of
  commands will be executed.

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Example of Conditional Statements

• For example -
• If the light is lt50
• Set Direction Forward
• Move Forward for 3 s
• Stop
• Else If light is gt 50
• Stop
• End

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Quiz

• What are the 3 types of control structures?
• Which would work best for the following
  situations -
• Robotic wheelchair executes a left turn.
• Robot wheelchair backs up if it hits the wall.
• Car moves back and forth across crosswalk.

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RCX Programming
Commands Tell robot what to do (e.g. stop, go,
turn, etc.).
Sensor Watchers Test conditions (e.g. light,
touch, count) and determine actions based on
conditions.
Stack Controllers Allows robot to repeat
commands or wait until condition is true.
My Commands Makes several actions a
subroutine which can be used as a single
command.
See handout for more information!
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Before using- Download Firmware

• click on Getting Started and then Set Up
  Options

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Features of RCX software

• Multi-threaded language
• Different parts of the program execute at the
  same time.
• Can cause unexpected results!
• Loops in main program interfere with subprogram.
• Variables limited to 1 or 0
• Use counter as variable.
• Not Quite C (NQC) language allows for more
  variables.

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Thats all !

• Happy robot building and competition!

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What are we going to do today?

• Find your group.
• Get your robot.
• inventory
• Plan your project.
• Gantt chart
• Share your work
• Learn how to build a robot and communicate with
  it