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Robot Building for Beginners

Book Description

Robot Building for Beginners is an update of David Cook's best-selling Robot Building for Beginners. This book continues its aim at teenagers and adults who have an avid interest in science and dream of building household explorers. No formal engineering education is assumed.

Table of Contents

  1. Copyright
  2. About the Author
  3. About the Technical Reviewer
  4. Acknowledgments
  5. Introduction
    1. Intended Audience
      1. "Where's the stuff about the killer saws?"
      2. "Houston, we have a problem."
      3. Not Ready to Learn How to Solder?
      4. Beyond LEGO But Still Not Ready to Solder?
    2. Note Regarding Part Lists
    3. Getting Updates and Seeing What's New
  6. 1. Welcome Robot Inventor!
    1. 1.1. Four Disciplines
    2. 1.2. Anatomy of a Homemade Robot
      1. 1.2.1. Brains
      2. 1.2.2. Electrical Power
        1. 1.2.2.1. Power Source
        2. 1.2.2.2. Power Regulation
        3. 1.2.2.3. On/Off Switch
      3. 1.2.3. Sensors
        1. 1.2.3.1. Pushbuttons
      4. 1.2.4. Action and Feedback
        1. 1.2.4.1. Movement
          1. 1.2.4.1.1. Motor Controller
        2. 1.2.4.2. Indicator Lights
      5. 1.2.5. Miscellaneous Components
      6. 1.2.6. Body
        1. 1.2.6.1. Aesthetics
    3. 1.3. Building Up
      1. 1.3.1. Taking Small Bites
      2. 1.3.2. Making Modules
      3. 1.3.3. Keeping It Fun and Keeping It Light
      4. 1.3.4. Finding Camaraderie and Support
    4. 1.4. Onward and Upward
  7. 2. Where to Obtain Tools and Parts
    1. 2.1. Ordering Free Information
    2. 2.2. Discovering Hidden Messages
      1. 2.2.1. Considering Columns
      2. 2.2.2. Counting Pages
      3. 2.2.3. Comparing Prices
    3. 2.3. Saving Money
  8. 3. Safety
    1. 3.1. Benefiting from Age and Experience
    2. 3.2. Following Instructions
    3. 3.3. Reading Chemical Labels
    4. 3.4. Donning Safety Glasses
      1. 3.4.1. Hanging Glasses and Placing Them Face Up
    5. 3.5. Wearing Other Safety Clothes
    6. 3.6. Insuring Adequate Ventilation
    7. 3.7. Storing Properly
      1. 3.7.1. Talking About Your Activities, Materials, and Tools
    8. 3.8. Washing Before Eating
    9. 3.9. Avoiding Nasty Elements
      1. 3.9.1. Lead
      2. 3.9.2. Mercury
      3. 3.9.3. Cadmium
      4. 3.9.4. Purchasing Safer Parts Labeled RoHS
    10. 3.10. Shocking
      1. 3.10.1. AC vs. DC
      2. 3.10.2. Using Rechargeable Batteries and Professional Transformers
      3. 3.10.3. Connecting Through Circuit Breakers and GFCI Outlets
      4. 3.10.4. Saving the Ground Prong
      5. 3.10.5. Disconnecting Power
    11. 3.11. Steering Clear of Dangerous Robots
    12. 3.12. Sizing Up Motors
    13. 3.13. Lighting Up
    14. 3.14. Staying Rested and Level-Headed
  9. 4. Digital Multimeter
    1. 4.1. Must-Have Features
      1. 4.1.1. Digital
      2. 4.1.2. Digits
      3. 4.1.3. DC Voltage
      4. 4.1.4. DC Current
      5. 4.1.5. Resistance
      6. 4.1.6. Probes or Leads
      7. 4.1.7. Overload/Fuse Protection
    2. 4.2. Nice-To-Have Features
      1. 4.2.1. Capacitance
      2. 4.2.2. Diode
      3. 4.2.3. Continuity
      4. 4.2.4. Frequency
      5. 4.2.5. Duty Cycle
      6. 4.2.6. Autoranging
      7. 4.2.7. Auto Power Off
      8. 4.2.8. Transistor
      9. 4.2.9. Dual Display
      10. 4.2.10. Maximum
      11. 4.2.11. Minimum
      12. 4.2.12. Stand
    3. 4.3. Optional Features
      1. 4.3.1. Inductance
      2. 4.3.2. RS-232/USB Data Interface
      3. 4.3.3. Scope
      4. 4.3.4. Backlight
      5. 4.3.5. Stopwatch/Single Pulse Width
      6. 4.3.6. Temperature
      7. 4.3.7. Sound
      8. 4.3.8. Count
      9. 4.3.9. Bar Graph
      10. 4.3.10. Data Hold
      11. 4.3.11. Data Auto
      12. 4.3.12. High/Low/Logic
      13. 4.3.13. Memory
      14. 4.3.14. Relative
      15. 4.3.15. Offset
      16. 4.3.16. Limit Testing/Compare
      17. 4.3.17. Holster or Rubber Boot
    4. 4.4. AC Features
      1. 4.4.1. AC Voltage
      2. 4.4.2. True RMS
      3. 4.4.3. AC Current
    5. 4.5. Obtaining Hook Probe Adaptors
    6. 4.6. Comparing Actual Multimeters
      1. 4.6.1. Understanding the Features of a Low-End Multimeter
      2. 4.6.2. Understanding the Features of a Mid-Range Multimeter
      3. 4.6.3. Understanding the Features of a Higher-End Multimeter
      4. 4.6.4. Comparing Prices with Features
    7. 4.7. Proceeding Without a Meter
  10. 5. Numbers and Units
    1. 5.1. Choosing the Metric System
    2. 5.2. Reducing Powers of a Thousand
      1. 5.2.1. M & m
      2. 5.2.2. Alternative for Greek Micro
    3. 5.3. Abbreviating Units
    4. 5.4. Too Little
      1. 5.4.1. Guessing Missing Units
      2. 5.4.2. Expanding from Three Digits
      3. 5.4.3. Converting Colors to Numbers
      4. 5.4.4. Determining Component Values with a Multimeter
    5. 5.5. Base Subjects Covered
  11. 6. Robot Line-Following
    1. 6.1. Defining the Course Conditions
      1. 6.1.1. Surface Materials
      2. 6.1.2. Course Lighting
      3. 6.1.3. Defining the Line
        1. 6.1.3.1. Picking Line Marking Material
      4. 6.1.4. Curving and Crossing Lines
      5. 6.1.5. Summarizing Course Conditions
    2. 6.2. Picking the Robot's Size
    3. 6.3. Seeing Sandwich
      1. 6.3.1. Examining Sandwich
        1. 6.3.1.1. Line-Following Switch
        2. 6.3.1.2. Power Source and Power Switch
        3. 6.3.1.3. Sensors and Headlights
          1. 6.3.1.3.1. Placing the Robot on the Center of the Line
          2. 6.3.1.3.2. Adjusting Sensor Balance
        4. 6.3.1.4. Brighter-Side Indicators
        5. 6.3.1.5. The Brains
        6. 6.3.1.6. The Muscle
          1. 6.3.1.6.1. Fitting and Changing Wheels
      2. 6.3.2. Sandwich Body
        1. 6.3.2.1. Connecting It Together
          1. 6.3.2.1.1. Physical Connections
          2. 6.3.2.1.2. Electrical Connections
    4. 6.4. Obtaining a Kit
    5. 6.5. Building Up
  12. 7. Nine-Volt Batteries
    1. 7.1. Testing Battery Voltage
      1. 7.1.1. Setting Up a Multimeter for Voltage Testing
      2. 7.1.2. Interpreting Test Results
    2. 7.2. 9 V Battery Characteristics
    3. 7.3. 9 V Battery Recommendations
      1. 7.3.1. Recommended
      2. 7.3.2. Nickel-Metal Hydride
        1. 7.3.2.1.
          1. 7.3.2.1.1. Retaining Charge When Not in Use
      3. 7.3.3. Lithium-Polymer
      4. 7.3.4. Alkaline
      5. 7.3.5. Specialized Use
      6. 7.3.6. Lithium
      7. 7.3.7. Not Recommended
        1. 7.3.7.1. Carbon and Zinc
        2. 7.3.7.2. Nickel-Cadmium
        3. 7.3.7.3. e2 Titanium and Ultra
    4. 7.4. Battery Brand Names
    5. 7.5. Using 9 V Batteries in Robots
      1. 7.5.1. Mounting Batteries
    6. 7.6. Powering Forward
  13. 8. Clips and Test Leads
    1. 8.1. The Gators Are Hungry Tonight
    2. 8.2. Obtaining Hook Clips
    3. 8.3. Testing Jumpers
      1. 8.3.1. Setting Up a Multimeter for Continuity Testing
      2. 8.3.2. Testing an Open Connection
      3. 8.3.3. Testing a Shorted Connection
      4. 8.3.4. Testing an Alligator Connection (Shorted)
    4. 8.4. Discovering Unintended Connections
    5. 8.5. Plumbing with Jumpers
  14. 9. Resistors
    1. 9.1. Limiting Power with Resistors
    2. 9.2. Obtaining a Resistor Variety Pack
    3. 9.3. Understanding Size and Tolerance
    4. 9.4. Cut It Out
      1. 9.4.1. Obtaining a Wire Cutter Tool
    5. 9.5. Resistance and Ohms
    6. 9.6. Measuring Resistance
      1. 9.6.1. Interpreting the Resistance Displayed on the Meter
      2. 9.6.2. Experiencing Resistance Ranges
    7. 9.7. Looking Up Resistor Values Online
    8. 9.8. Labeling and Storing
      1. 9.8.1. Obtaining Storage Cases
    9. 9.9. Resisting the Temptation to Skip Ahead
  15. 10. LEDs
    1. 10.1. Learning About LED Attributes
      1. 10.1.1. LED Sizes
        1. 10.1.1.1. Using Calipers to Measure LED Diameter
      2. 10.1.2. LED Shapes
      3. 10.1.3. LED Lens Clarities
        1. 10.1.3.1. Water Clear
        2. 10.1.3.2. White Diffused
        3. 10.1.3.3. Colored Diffused
      4. 10.1.4. LED Viewing Angles
      5. 10.1.5. LED Colors
        1. 10.1.5.1. Relating Color to a Wavelength
        2. 10.1.5.2. Indicating Color via the CIE Standard Colorimetric System
      6. 10.1.6. LED Brightness
        1. 10.1.6.1. Super Ultra High Brightness to the Max
      7. 10.1.7. LED Efficiency
    2. 10.2. Extreme Close Up of an LED
    3. 10.3. Identifying Multicolor LEDs
      1. 10.3.1. Bicolor
      2. 10.3.2. Tricolor or Tri-state
      3. 10.3.3. Full Color
    4. 10.4. Testing an LED
      1. 10.4.1. Setting Up a Multimeter for Diode Testing
      2. 10.4.2. Interpreting LED Test Results
        1. 10.4.2.1. Forward Voltage Drop
    5. 10.5. Variety Pack
    6. 10.6. Brightening Your Way
  16. 11. Power On!
    1. 11.1. Introducing the Parts List
      1. 11.1.1. Testing the Parts Before Assembly
    2. 11.2. Reading a Schematic
    3. 11.3. Building the Power Indicator Circuit
      1. 11.3.1. Do You See The Light?
      2. 11.3.2. Experimenting with the Power Indicator Circuit
    4. 11.4. Understanding the Roles of Each Component
    5. 11.5. Measuring the Power Indicator Circuit
      1. 11.5.1. Measuring In-Circuit Voltage
        1. 11.5.1.1. Measuring Voltage "At" a Point
        2. 11.5.1.2. Measuring Voltage "Drop" or Voltage "Across" a Part
        3. 11.5.1.3. Summarizing Circuit Voltage
      2. 11.5.2. Measuring Current Flow
      3. 11.5.3. Calculating Battery Life
        1. 11.5.3.1. Extending Battery Life
        2. 11.5.3.2. Selecting Resistors
        3. 11.5.3.3. Calculating Current
          1. 11.5.3.3.1. Minimum Resistor for LED Formula
      4. 11.5.4. Don't Measure Voltage with Probe in Current Terminal
    6. 11.6. Circuit Summary
  17. 12. Solderless Prototyping
    1. 12.1. Needing A Better Way
    2. 12.2. Solderless Breadboards
      1. 12.2.1. Connecting with Holes
        1. 12.2.1.1. 5-Position Group
        2. 12.2.1.2. Center Gap
        3. 12.2.1.3. 25-Position Distribution Bus
      2. 12.2.2. Binding Posts
        1. 12.2.2.1. Banana Plugs
      3. 12.2.3. Hungry for Breadboards
    3. 12.3. Solderless Breadboard Wire
      1. 12.3.1. Choosing Jumper Wire
        1. 12.3.1.1. Obtaining Reinforced Jumper Wire
        2. 12.3.1.2. Obtaining Flat, Ready-Made Jumper Wire
    4. 12.4. Making Your Own Jumper Wire
      1. 12.4.1. Stripping the Insulation Off of the End of the Wire
        1. 12.4.1.1. Choosing Wire Strippers
      2. 12.4.2. Cutting the Wire to Length
      3. 12.4.3. Bending the End of the Wire
        1. 12.4.3.1. Selecting Electrical Pliers
          1. 12.4.3.1.1. Obtaining Smooth-Jaw Needle-Nose Pliers
          2. 12.4.3.1.2. Obtaining Serrated-Jaw Long-Nose Pliers
    5. 12.5. Making The Connection
  18. 13. Solderless Breadboard Setup
    1. 13.1. Considering Power Sources
      1. 13.1.1. Obtaining 9 V Battery Snap Connectors
      2. 13.1.2. Connecting Power to Binding Posts
    2. 13.2. Choosing a Power Switch
      1. 13.2.1. Understanding SPDT
      2. 13.2.2. Adding a Power Switch to the Breadboard
    3. 13.3. Connecting Power Buses
      1. 13.3.1. Adapting Multimeter Probes Using Jumper Wire
      2. 13.3.2. Connecting the Lower Bus
      3. 13.3.3. Split Down the Middle
    4. 13.4. Installing a Power Indicator LED
      1. 13.4.1. Checking Voltages at Certain Points
      2. 13.4.2. Trimming Leads
    5. 13.5. Demystifying the Robot's Power Switch
    6. 13.6. Ready for More
  19. 14. Variable Resistors
    1. 14.1. Potentiometers
      1. 14.1.1. Trimpot
      2. 14.1.2. Turning the Dial
      3. 14.1.3. Obtaining Assorted Trimpots
      4. 14.1.4. Testing Potentiometers
        1. 14.1.4.1. Measuring the Maximum Resistance of a Potentiometer
        2. 14.1.4.2. Measuring the Variable Resistance of a Potentiometer
        3. 14.1.4.3. Linear Versus Logarithmic/Exponential
    2. 14.2. Variable Brightness LED Circuit
      1. 14.2.1. Building the Variable Brightness LED Circuit
    3. 14.3. Brightness Balancing Circuit
      1. 14.3.1. Building the Brightness Balanced LEDs Circuit
    4. 14.4. Cadmium-Sulfide Photoresistors
      1. 14.4.1. Obtaining Assorted Photoresistors
      2. 14.4.2. Experiencing the Variable Resistance of a Photoresistor
    5. 14.5. Light-Controlled Circuit
    6. 14.6. Balanced Brightness-Sensing Circuit
      1. 14.6.1. Part List for Balanced Brightness-Sensing Circuit
      2. 14.6.2. Brightness-Sensing Pairs
      3. 14.6.3. Matching Photoresistors
      4. 14.6.4. Resistance-Balancing Potentiometer
      5. 14.6.5. Current-Limiting Resistor
      6. 14.6.6. Test Points
        1. 14.6.6.1. Calculating the Voltages
        2. 14.6.6.2. Evaluating Test Point 1
      7. 14.6.7. Converting Resistance to Voltage with a Voltage Divider
      8. 14.6.8. Building the Balanced Brightness-Sensing Circuit
      9. 14.6.9. Inability to Balance the Brightness-Sensing Circuit
  20. 15. Comparators
    1. 15.1. Voltage Comparator
      1. 15.1.1. Examining the LM393
        1. 15.1.1.1. Turning to the Datasheet
        2. 15.1.1.2. Inspecting the Pinouts
          1. 15.1.1.2.1. Locating the Power Supply Pins
          2. 15.1.1.2.2. Identifying the Comparators
      2. 15.1.2. Obtaining Comparators
    2. 15.2. Brightness Comparator Circuit
      1. 15.2.1. Comparing a Schematic with a Wiring Diagram
      2. 15.2.2. Labeling Parts
      3. 15.2.3. Drawing Connected and Unconnected Wire
      4. 15.2.4. Understanding the Brightness Comparator Circuit
      5. 15.2.5. Parts List for the Brightness Comparator Circuit
      6. 15.2.6. Building the Brightness Comparator Circuit
        1. 15.2.6.1. Having Fun with the LED Indicators and Light Sensors
        2. 15.2.6.2. Diagnosing Problems in the Brightness Comparator Circuit
          1. 15.2.6.2.1. Confirming Power Across the Board
          2. 15.2.6.2.2. Faking Input to the Comparator
    3. 15.3. Adding Headlights
      1. 15.3.1. Understanding the Headlight Circuit's Two LEDs
      2. 15.3.2. Building the Headlight Circuit
      3. 15.3.3. Repeating the Multiple LED Trick
        1. 15.3.3.1. Determining the Number of LEDs that the Battery Voltage Can Support
        2. 15.3.3.2. Calculating the Maximum Current Draw
    4. 15.4. Appreciating a Simple Mind
  21. 16. Transistor Switches
    1. 16.1. Defining Negative Power
      1. 16.1.1. Focusing on the 2907A Transistor
        1. 16.1.1.1. Pushing the 2907A's Button
        2. 16.1.1.2. Checking the Datasheet
        3. 16.1.1.3. Obtaining 2907A Transistors
    2. 16.2. Testing Bipolar Transistors with a Multimeter
      1. 16.2.1. Testing with a Multimeter that Has a Transistor Socket
        1. 16.2.1.1. Testing a Transistor When You Have the Datasheet
          1. 16.2.1.1.1. Understanding the Importance of Transistor Gain
          2. 16.2.1.1.2. Gain Varies from Transistor to Transistor
          3. 16.2.1.1.3. Switching Off and On Rather Than Amplifying
        2. 16.2.1.2. Testing a Transistor When You Don't Have the Datasheet
      2. 16.2.2. Testing with a Multimeter that Has a Diode Test
    3. 16.3. Bipolar Transistor Test Circuits
      1. 16.3.1. Examining the Schematic for the PNP Transistor Test Circuit
        1. 16.3.1.1. Dimming the LED for Reverse Connections
      2. 16.3.2. Building the PNP Transistor Test Circuit
        1. 16.3.2.1.
          1. 16.3.2.1.1. Correcting Problems with the PNP Transistor Test Circuit
          2. 16.3.2.1.2. Experimenting with the Functioning PNP Transistor Test Circuit
          3. 16.3.2.1.3. Gathering Data About the PNP Transistor
      3. 16.3.3. Examining the Schematic for the NPN Transistor Test Circuit
      4. 16.3.4. Building the NPN Transistor Test Circuit
    4. 16.4. Brightness Comparator Circuit with Transistors
      1. 16.4.1. Calculating Current-Limiting Transistors
        1. 16.4.1.1. Identifying Stresses Beyond Official Limitations
          1. 16.4.1.1.1. Taking Into Account the LM393's Worst-Case Minimum Limit
          2. 16.4.1.1.2. Looking Out for Heavy Current Through the Attached Circuit
      2. 16.4.2. Building the Brightness Comparator Circuit with Transistors
    5. 16.5. Summarizing PNP and NPN Transistors
  22. 17. DC Motors
    1. 17.1. How DC Motors Work
      1. 17.1.1. Looking Inside an Iron-Core Permanent-Magnet DC Brush Motor
        1. 17.1.1.1. Stator
        2. 17.1.1.2. Rotor
          1. 17.1.1.2.1. Rotor Windings
          2. 17.1.1.2.2. Rotor Shoes
          3. 17.1.1.2.3. Rotor Commutator
          4. 17.1.1.2.4. Rotor Brushes
      2. 17.1.2. Looking Inside an Iron-Core Permanent-Magnet DC Brushless Motor
        1. 17.1.2.1.
          1. 17.1.2.1.1. Living Longer Without Brushes
          2. 17.1.2.1.2. Switching with Brushless Circuitry
          3. 17.1.2.1.3. Limitations of Brushless Motors
      3. 17.1.3. Looking Inside a Coreless Permanent-Magnet DC Brush Motor
        1. 17.1.3.1. Comparing Coreless vs. Iron Core
    2. 17.2. Simple DC Motor Circuit
      1. 17.2.1. Selecting a Motor for the Simple DC Motor Circuit
      2. 17.2.2. Selecting a Battery for the Simple DC Motor Circuit
      3. 17.2.3. Building the Simple DC Motor Circuit
    3. 17.3. Primary Characteristics of DC Motors
      1. 17.3.1. Rotational Speed Characteristic of DC Motors
        1. 17.3.1.1. Measuring RPM
          1. 17.3.1.1.1. Mounting Putty Aids Motor Experimentation
        2. 17.3.1.2. Converting RPM to a Metric Unit
      2. 17.3.2. Torque Characteristic of DC Motors
        1. 17.3.2.1. The Significance of Distance in Torque
        2. 17.3.2.2. Sliding Torque
        3. 17.3.2.3. Calculating Torque Needed for a Robot
      3. 17.3.3. Voltage Characteristic of DC Motors
        1. 17.3.3.1. Understanding the Relationship Between Voltage and Speed
          1. 17.3.3.1.1. Watching Out for the Relationship Between Voltage and Speed
      4. 17.3.4. Current Characteristic of DC Motors
        1. 17.3.4.1. Examining Periods of Widely Changing Current Consumption
          1. 17.3.4.1.1. Start-Up Current
          2. 17.3.4.1.2. No-Load Current
          3. 17.3.4.1.3. Load Current
          4. 17.3.4.1.4. Stall Current
        2. 17.3.4.2. Planning for Current Consumption
      5. 17.3.5. Efficiency Characteristic of DC Motors
      6. 17.3.6. Audible Noise Characteristic of DC Motors
        1. 17.3.6.1.
          1. 17.3.6.1.1. Oiling the Rotor Shaft
      7. 17.3.7. Electrical Noise Characteristic of DC Motors
      8. 17.3.8. Mass Characteristic of DC Motors
      9. 17.3.9. Dimension Characteristic of DC Motors
      10. 17.3.10. Summarizing the Characteristics of DC Motors
    4. 17.4. DC Gearhead Motors
      1. 17.4.1. Looking Inside a Spur Gearhead Motor
        1. 17.4.1.1. Revealing Pairs of Smaller and Larger Gears
        2. 17.4.1.2. Gearbox Shaft
      2. 17.4.2. Describing Gear Ratios
        1. 17.4.2.1. Absolute Gear Ratio
        2. 17.4.2.2. Simplified Gear Ratio
        3. 17.4.2.3. Odd Gear Ratios
        4. 17.4.2.4. Indicating Both Absolute and Simplified Gear Ratios
        5. 17.4.2.5. Using a Colon
        6. 17.4.2.6. Looking at Real Gears
      3. 17.4.3. Imperfect Speed to Torque Conversion
      4. 17.4.4. Disadvantages of Gearheads
      5. 17.4.5. Comparing Planetary Versus Spur Gearhead Motors
      6. 17.4.6. Choosing a Gearhead Motor
    5. 17.5. Moving Forward
  23. 18. Adding Gearhead Motors
    1. 18.1. Selecting Gearhead Motors
      1. 18.1.1. Obtaining the Gearhead Motors
      2. 18.1.2. Inspecting the Gearhead Motor
        1. 18.1.2.1. Current Usage of the Gearhead Motor
          1. 18.1.2.1.1. Determining the Least Current (Best Case)
          2. 18.1.2.1.2. Determining the Most Current (Worst Case)
          3. 18.1.2.1.3. Determining the Actual Current (Average Case)
    2. 18.2. Adding Motors to the Brightness Comparator Circuit
      1. 18.2.1. Introducing the Diode
        1. 18.2.1.1. Protecting the Transistor with a Flyback Diode
        2. 18.2.1.2. Picking the Schottky Barrier Diode
        3. 18.2.1.3. Obtaining Schottky Barrier Diodes
      2. 18.2.2. Building the Motors onto the Brightness Comparator Circuit
        1. 18.2.2.1. Connecting the Diode in the Proper Orientation
        2. 18.2.2.2. Connecting the Motor
        3. 18.2.2.3. Repeating the Setup for the Other Transistor
        4. 18.2.2.4. Testing the Motors
    3. 18.3. Completing the Electronics
  24. 19. Wheels
    1. 19.1. Anatomy of a Wheel
    2. 19.2. Characteristics of Robot Wheels
      1. 19.2.1. Creamy Air Filling
        1. 19.2.1.1. Effects of Air
      2. 19.2.2. Tire Shapes
      3. 19.2.3. Tire Width
      4. 19.2.4. Tread Designs
      5. 19.2.5. Tire Diameter
        1. 19.2.5.1. Calculating Linear Speed
      6. 19.2.6. Selecting Robot Wheels
        1. 19.2.6.1. Reasons for Choosing LEGO Wheels
    3. 19.3. Wheel Choice for Sandwich
      1. 19.3.1. Determining Minimum and Maximum Diameter
      2. 19.3.2. Determining the Maximum Diameter Based on Speed
      3. 19.3.3. My Choice of Wheels for Sandwich
      4. 19.3.4. Alternative Choices of Wheels for Sandwich
        1. 19.3.4.1. Compensating for Larger Wheels with Lower Voltage Batteries
        2. 19.3.4.2. Obtaining New Alternative Wheels
    4. 19.4. Cleaning Tires
    5. 19.5. Rolling Along
  25. 20. Coupler
    1. 20.1. Alternatives
      1. 20.1.1. Making Couplers If You Have Metal-Working Equipment
    2. 20.2. Tubing
      1. 20.2.1. Choosing Between Brass and Aluminum Tubing
      2. 20.2.2. Specifying and Obtaining Tubing Sizes
        1. 20.2.2.1. Telescoping Tubing Required
        2. 20.2.2.2. Fitting the LEGO Cross Axle into a Tube
        3. 20.2.2.3. Fitting the Motor Shaft into a Tube
    3. 20.3. Measuring and Cutting the Tubing
      1. 20.3.1. Determining and Marking Tube Lengths
      2. 20.3.2. Cutting Tubing
        1. 20.3.2.1. Tube Cutter Tool
        2. 20.3.2.2. Variable-Speed Rotary Tool
          1. 20.3.2.2.1. Securing the Tubing in a Vise
          2. 20.3.2.2.2. Cutting the Tubing with a High-Speed Rotary Tool
      3. 20.3.3. Finishing the Cut by Sanding
      4. 20.3.4. Testing the Cut Pieces
    4. 20.4. LEGO Cross Axles
      1. 20.4.1. Selecting a LEGO Cross Axle Length
      2. 20.4.2. Obtaining LEGO Cross Axles
    5. 20.5. Gluing the Coupler Together
      1. 20.5.1. Coming Unglued
        1. 20.5.1.1. Notching the Cross Axle
      2. 20.5.2. Using Epoxy
        1. 20.5.2.1. Removing Extraneous Epoxy
    6. 20.6. Adding a Setscrew to the Coupler
      1. 20.6.1. Marking a Hole for the Setscrew
      2. 20.6.2. Drill Press
      3. 20.6.3. Drill-Press Vise
      4. 20.6.4. Drilling the Hole for the Setscrew
      5. 20.6.5. Tapping the Hole for the Setscrew
      6. 20.6.6. Inserting the Setscrew
    7. 20.7. Admiring the Coupler
  26. 21. Soldering Equipment
    1. 21.1. Solder Wire
    2. 21.2. Flux
    3. 21.3. Soldering Iron
    4. 21.4. Soldering Stand
    5. 21.5. Soldering Sponge
    6. 21.6. Helping-Hand Tool
    7. 21.7. Desoldering Vacuum Tools
    8. 21.8. Steps of a Typical Soldering Session
    9. 21.9. Get Ready to Solder
  27. 22. Soldering and Connecting
    1. 22.1. Putting Together the Motors and Switches
      1. 22.1.1. Putting Together the Motors
        1. 22.1.1.1. Preparing and Attaching the Motor Wires
        2. 22.1.1.2. Holding the Motor Firmly and Preparing the Soldering Iron
        3. 22.1.1.3. Soldering the Motors
          1. 22.1.1.3.1. In Soldering, Practice Makes Perfect
        4. 22.1.1.4. Protecting Soldered Joints with Heat-Shrink Tubing
          1. 22.1.1.4.1. Obtaining Heat-Shrink Tubing
          2. 22.1.1.4.2. Protecting the Motor Terminals with Heat-Shrink Tubing
        5. 22.1.1.5. Adding Connectors
          1. 22.1.1.5.1. Molex KK Connectors
          2. 22.1.1.5.2. Obtaining Molex KK Equipment
          3. 22.1.1.5.3. Attaching Molex KK Connectors to the Motors
      2. 22.1.2. Putting Together the Line-Following Switch
        1. 22.1.2.1. Obtaining the Line-Following Switch
        2. 22.1.2.2. Preparing and Attaching the Switch Wires
        3. 22.1.2.3. Soldering the Line-Following Switch
          1. 22.1.2.3.1. Reasoning Behind the Diagonal Cross Over
          2. 22.1.2.3.2. Finishing Soldering the Line-Following Switch
      3. 22.1.3. Putting Together the Tube LED Circuit
        1. 22.1.3.1. Examining the Tube LED Circuit Schematic
        2. 22.1.3.2. Building the Tube LED Circuit
      4. 22.1.4. Finishing Up
        1. 22.1.4.1. Obtaining the Power Switch
    2. 22.2. Soldering Experience
  28. 23. The Motherboard
    1. 23.1. The Line-Following Circuit
      1. 23.1.1. Tweaking For Better Performance
      2. 23.1.2. Point-to-Point Soldering Versus a Printed Circuit Board
      3. 23.1.3. Point-to-Point Soldering the Line-Following Circuit
        1. 23.1.3.1. Laying Out the Line-Following Circuit Components
          1. 23.1.3.1.1. Placing Components with a Helping Hand
          2. 23.1.3.1.2. Example Layout
          3. 23.1.3.1.3. Obtaining an IC Socket
        2. 23.1.3.2. Keeping the Components on the Board During Soldering
          1. 23.1.3.2.1. Gluing the Molex KK Headers to the Circuit Board
          2. 23.1.3.2.2. Bending Component Leads
        3. 23.1.3.3. Creating Power Distribution Buses
        4. 23.1.3.4. Soldering the Remaining Components
          1. 23.1.3.4.1. Soldering the Cadmium-Sulfide Photoresistors
        5. 23.1.3.5. Trimming Leads with Wire Snips
        6. 23.1.3.6. Cleaning the Board
    2. 23.2. Testing the Robot's Electronics
      1. 23.2.1. The Dangers of a Low-Resistance Circuit
      2. 23.2.2. Checking for Unsoldered Leads
      3. 23.2.3. Checking All Leads that Connect Directly to Positive Voltage
      4. 23.2.4. Measuring the Resistance of the Entire Circuit
        1. 23.2.4.1. Measuring the Power Off Resistance
        2. 23.2.4.2. Measuring the Power On Resistance
        3. 23.2.4.3. Measuring the Sensor Resistance
      5. 23.2.5. Measuring the Voltage Drop
      6. 23.2.6. Reheating Solder Joints
    3. 23.3. Holding Your Breath
  29. 24. Body Building
    1. 24.1. Approaching Robot Bodies
      1. 24.1.1. Ethereal Drafting—Thinking About the Robot
      2. 24.1.2. Vision Revision—Accepting Constraints Based on Available Parts
      3. 24.1.3. Designing Custom Bodies
        1. 24.1.3.1. Plastic Prototyping—Constructing Models with LEGO Bricks
        2. 24.1.3.2. Material Substitution—Transitioning Out LEGO Parts
        3. 24.1.3.3. Origami Helper—Bending Paper Before Bending Metal
      4. 24.1.4. Embracing Prefabricated Platforms
        1. 24.1.4.1. Commercially Available Robot Platforms
        2. 24.1.4.2. Converting and Recycling Everyday Items for Robot Bodies
    2. 24.2. Transforming the Sandwich Container
      1. 24.2.1. Creating Motor Holes
        1. 24.2.1.1. Marking and Determining Space Required By the Circuit Board
        2. 24.2.1.2. Creating a Template Sticker for the Motor Holes
        3. 24.2.1.3. Positioning the Template Stickers on the Container's Sides
        4. 24.2.1.4. Making Pilot Holes and Drilling Screw Holes
        5. 24.2.1.5. Introducing the Grinding Stone Accessory
      2. 24.2.2. Mounting the Motors
        1. 24.2.2.1. Obtaining Metric Screws
        2. 24.2.2.2. Needing Washers
      3. 24.2.3. Creating the Motor Tube
        1. 24.2.3.1. Obtaining the Motor Tube
        2. 24.2.3.2. Cutting the Motor Tube
        3. 24.2.3.3. Sanding the Motor Tube
        4. 24.2.3.4. Removing the Label Residue
        5. 24.2.3.5. Widening the Motor Diameters
      4. 24.2.4. Installing the Motors and Tube
      5. 24.2.5. Adding the Switches and Battery Holder
        1. 24.2.5.1. Installing the Power Switch
        2. 24.2.5.2. Installing the Line-Following Switch
        3. 24.2.5.3. Installing the 9 V Battery Holder
      6. 24.2.6. Adding the Circuit Board
        1. 24.2.6.1. Circuit Board Mounting Hardware
        2. 24.2.6.2. Selecting and Obtaining Spacers
        3. 24.2.6.3. Installing the Circuit Board
      7. 24.2.7. Drilling Holes for the Trimpots
      8. 24.2.8. Carving Out a Window in the Container Lid
      9. 24.2.9. Finishing Touches
    3. 24.3. Ready to Roll
  30. 25. Launching the Line-Follower
    1. 25.1. Correcting and Tweaking
      1. 25.1.1. Preliminary Examination
        1. 25.1.1.1. Checking the Power Supply
        2. 25.1.1.2. Checking the Sensors
        3. 25.1.1.3. Balancing the Sensors
        4. 25.1.1.4. Checking the Motors
        5. 25.1.1.5. Determining the Light and Dark Positions of the Line-Following Switch
      2. 25.1.2. Trial Run: Following a Straight Line
      3. 25.1.3. Correcting Common Problems
        1. 25.1.3.1. Line-Following Switch Toggled to Incorrect Position
        2. 25.1.3.2. Sensors Placed Too High or Too Low
        3. 25.1.3.3. Headlights Too Dim or Too Bright
        4. 25.1.3.4. Objectively Evaluating the Sensors and Headlights
          1. 25.1.3.4.1. Expected Voltages at the Sensor Test Points
          2. 25.1.3.4.2. Acceptable Ranges of Voltages at the Sensor Test Points
      4. 25.1.4. Does This Look Straight to You?
        1. 25.1.4.1. Following a Dark Line
        2. 25.1.4.2. Following a Light Line
    2. 25.2. The Maiden Voyage
      1. 25.2.1. Solving Steering Problems
        1. 25.2.1.1. Reducing Battery Voltage
        2. 25.2.1.2. Reducing Wheel Size
        3. 25.2.1.3. Modifying the Course
    3. 25.3. Potential Improvements
      1. 25.3.1. Protecting Against a Reversed Battery
      2. 25.3.2. Eliminating Surges with Capacitors
      3. 25.3.3. Improving Line-Following
        1. 25.3.3.1. Analyzing Cornering, Frame By Frame
          1. 25.3.3.1.1. Braking to Pivot
    4. 25.4. Final Bow
  31. 26. Encore
    1. 26.1. Robot Components
      1. 26.1.1. Logic Chips
        1. 26.1.1.1. Beyond the Golden Age of Logic Chips
      2. 26.1.2. Microcontrollers
        1. 26.1.2.1. Capabilities of Microcontrollers
        2. 26.1.2.2. Microcontroller Costs
        3. 26.1.2.3. Choosing a Microcontroller
      3. 26.1.3. Voltage Regulators
        1. 26.1.3.1. Voltage Regulator Packages
        2. 26.1.3.2. Voltage Regulator Types
        3. 26.1.3.3. Selection Criteria
      4. 26.1.4. Capacitors
        1. 26.1.4.1. Capacitor Roles
        2. 26.1.4.2. Capacitor Characteristics
      5. 26.1.5. Solar Power
        1. 26.1.5.1. BEAM Robots
      6. 26.1.6. Resistor Networks
      7. 26.1.7. Pushbuttons
      8. 26.1.8. DIP Switches
      9. 26.1.9. Jumpers and Shorting Blocks
      10. 26.1.10. Tilt Sensor
      11. 26.1.11. Temperature Sensors
      12. 26.1.12. Touch Sensors
      13. 26.1.13. Object Detection and Infrared Remote Control
      14. 26.1.14. Distance and Object Sensor
      15. 26.1.15. Oscillators and Crystals
      16. 26.1.16. Sound
      17. 26.1.17. Relays
      18. 26.1.18. Adding Gears
      19. 26.1.19. Servos
      20. 26.1.20. Encoders—Determining Wheel Speed
      21. 26.1.21. Displays
      22. 26.1.22. Wireless Data and Control
    2. 26.2. Everyday Challenges
      1. 26.2.1. Houseplant-Watering Robot
      2. 26.2.2. Compost Cart
      3. 26.2.3. Trash Emptier
      4. 26.2.4. Window Washer
      5. 26.2.5. Roof Rat
      6. 26.2.6. Micro Snowplow
      7. 26.2.7. Slug Squisher
      8. 26.2.8. Automatic Street mailbox
    3. 26.3. Contests
      1. 26.3.1. Worldwide Robot Sumo
      2. 26.3.2. Trinity College Fire-Fighting
      3. 26.3.3. Atlanta Robot Vacuuming
      4. 26.3.4. Seattle Robotics Society Robothon
      5. 26.3.5. Dallas Personal Robotics Group Roborama
      6. 26.3.6. Central Illinois Robotics Club
      7. 26.3.7. Chicago Area Robotics Group (Chibots)
    4. 26.4. The Great Wide Open
  32. 27. Appendix
    1. 27.1. Magical Ohm's Law
      1. 27.1.1. Ohm's Law is Helpful in Selecting a Current-Limiting Resistor
      2. 27.1.2. Help in Determining Current from a Voltage
        1. 27.1.2.1. Multimeter Voltage to Current Trick
      3. 27.1.3. The Key Point of Ohm's Law
      4. 27.1.4. The Larger Implication of Ohm's Law
    2. 27.2. Things I've Accidentally Destroyed While Writing This Book
      1. 27.2.1. Which Way Does a 9 V Battery Get Installed?
      2. 27.2.2. Melting Switches
      3. 27.2.3. Popping Multimeter Fuses
      4. 27.2.4. Fool Me, Twice
    3. 27.3. Voltage's Real Name
      1. 27.3.1. Ground, Not Negative Voltage
      2. 27.3.2. V Double Letter
        1. 27.3.2.1. Practical Example