Intermediate Robot Building

Prelim......Page 1
Contents......Page 5
About the Author......Page 26
About the Technical Reviewer......Page 27
Acknowledgments......Page 28
Required Electronics and Machine Shop Experience......Page 30
Required Software Development Experience......Page 31
Preferred Robot Building Experience......Page 32
Safety Rules......Page 33
Getting Updates and Seeing What’s New......Page 34
Building Modules......Page 35
Arranging Chapters......Page 36
Stocking Your Machine Shop......Page 37
Using a Milling Machine......Page 39
Putting It All Together......Page 41
Assembling and Testing a Robot......Page 42
Applying Parts and Techniques to Other Robots......Page 43
Comparing Two Types of Homemade Motor Couplers and Common Errors to Avoid......Page 45
Examining Telescoping-Tube Couplers......Page 46
Comparing with Solid-Rod Couplers......Page 47
Identifying Desired Results in Coupler Drill Holes, Along with Common Errors and Their Effects......Page 48
Connecting the Setscrew Hole to the Motor Shaft Hole......Page 49
Accepting Parallel Offset Between the Holes and the Coupler Body......Page 50
Avoiding Parallel Offset Between the Holes Themselves......Page 52
Avoiding Angular Offset Between the Holes Themselves......Page 53
Getting Ready to Make a Solid-Rod Coupler......Page 55
Gathering Tools and Parts......Page 57
Measuring the Motor and Axle......Page 58
Selecting the Coupler Material......Page 59
Cutting the Solid Rod into Coupler-Size Pieces......Page 60
Smoothing the Ends of the Coupler Body Pieces......Page 61
Making a Coupler Fixture......Page 64
Cutting the Coupler Fixture Block......Page 65
Drilling the Coupler Fixture Setscrew Hole......Page 67
Drilling the Coupler Rod Hole in the Coupler Fixture......Page 69
Selecting Drills......Page 70
Fixing the Depth......Page 71
Drilling......Page 74
Getting the Money Shot......Page 75
Adding a Setscrew to the Coupler Fixture......Page 76
Drilling the Motor-Shaft and LEGO Axle Coupler Holes......Page 77
Examining the Coupler So Far......Page 80
Determining the Location for the Coupler Setscrew......Page 83
Drilling the Coupler Setscrew Hole......Page 84
Selecting a Bottom-Style Tap......Page 85
Comparing to a Taper-Style Tap......Page 86
Selecting a Setscrew......Page 87
Adding the LEGO Axle......Page 89
Summary......Page 91
Covers Skills Perfect for Building Compact Sumo Robots, Machining Round Parts (Including Making Homemade Wheels), Using Step Blo......Page 93
Protecting Against Bumps and Falls......Page 94
Making a Hub-Adapter Coupler......Page 95
Adapting the Motor Shaft’s Outer Diameter to the LEGO Wheel’s Inner Diameter......Page 96
Starting Simply with the Coupler Rod......Page 97
Determining the Size......Page 99
Cutting the Raw Sheet Down to Size......Page 100
Drilling the......Page 101
Milling Circles with a Rotary Table......Page 103
Drilling Screw Holes in the Discs......Page 107
Finishing the Inner and Outer Hub-Adapter Discs......Page 110
Coring the LEGO Hubs......Page 112
Securing the Hub During Machining......Page 113
Drilling Out the Center of the Hub......Page 114
Sanding Away the Remains of the Center of the Hub......Page 115
Fitting and Gluing the Inner Disc onto the Rod......Page 116
Summary......Page 118
Reading Schematics......Page 119
Connecting Wires......Page 120
Lettering Designations......Page 121
Labeling Parts......Page 122
Labeling Resistors......Page 123
Labeling Capacitors......Page 125
Labeling LEDs and IEDs......Page 127
Symbolizing Ground and Simplifying Wiring......Page 128
Using Solderless Breadboards......Page 129
Selecting a Solderless Breadboard......Page 130
Setting Up a Solderless Breadboard to Match the Photographs......Page 131
Selecting an AC Power Adapter......Page 132
Adding a Few Amenities......Page 134
Understanding Oscilloscope Traces......Page 135
Using Surface-Mount Components......Page 136
Sizing Down Surface-Mount......Page 137
Converting Surface-Mount Components to Through-Hole......Page 138
Summary......Page 140
Understanding Voltage Regulators......Page 141
The 7805 Linear Voltage Regulator......Page 142
Introducing a 7805-Based 5 V Power Supply......Page 143
Building the 7805-Based Power Supply......Page 145
Improving the Power Supply by Reducing the Minimum Required Unregulated Voltage......Page 147
Substituting an LM2940, MCP1702, or LP2954 for the 7805......Page 148
Substituting a Power MOSFET for the 1N5817......Page 149
Selecting a Low-Resistance P-Channel Power MOSFET......Page 151
Analyzing the Minimum Input Voltage of Various Linear Regulator Circuits......Page 152
Presenting the Input/Output Voltage Results of Three 5 V Linear Voltage Regulators......Page 156
Protecting Against Short Circuits......Page 158
Protecting Against Thermal Overload......Page 159
Isolating Power and Noise......Page 160
Selecting a Linear Voltage Regulator for Your Robot......Page 162
Changing Marketplace Is Limiting 5 V Linear Regulator Selection......Page 163
Heading into Optimizations......Page 164
Bulking Up the Input and Output Capacitors......Page 165
Delayed Power-Off Because of Bulk Capacitors......Page 167
Using a DPDT Power Switch to Reduce Turn-Off Time......Page 169
Implementing Higher Margins of Safety for Tantalum Capacitors......Page 170
Adding Voodoo Capacitors......Page 171
Sprinkling with Bypass/Decoupling Capacitors......Page 172
Bypassing the Long Path to the Power Supply......Page 173
Selecting Bypass/Decoupling Capacitors......Page 174
Protecting with a Fuse......Page 175
Greatly Increasing Resistance to Greatly Reduce Current......Page 176
Installing PPTC Overcurrent-Protection Devices......Page 177
Selecting PPTC Overcurrent-Protection Devices......Page 179
Introducing the Zener Diode......Page 180
Using a Zener Diode to Short Circuit Power Upon Overvoltage......Page 181
Tripping Overcurrent Protection with the Overvoltage Short Circuit......Page 182
Purchasing Zener Diodes......Page 183
Putting It All Together for a Robust Robot Power Supply......Page 184
Why a Motor Driver?......Page 187
Supplying Motor Power from Unregulated vs. Regulated Power......Page 188
Demonstrating the Four Modes of a Motor......Page 189
Rotating Clockwise......Page 190
Using Up More Energy......Page 191
Driving Simply with a Single Transistor......Page 192
Introducing the NPN Bipolar Single-Transistor Motor-Driver Circuit......Page 194
Limiting Base Current with a Resistor......Page 195
Implementing the NPN Bipolar Single-Transistor Motor-Driver Circuit......Page 196
Introducing the PNP Bipolar Single-Transistor Motor-Driver Circuit......Page 198
Implementing the PNP Bipolar Single-Transistor Motor-Driver Circuit......Page 199
Implementing the Combination NPN and PNP Motor-Driver Circuit......Page 200
Avoiding a Short Circuit......Page 201
The Classic Bipolar H-Bridge......Page 202
Spinning Clockwise with an H-Bridge......Page 203
Spinning Counterclockwise with an H-Bridge......Page 204
Braking High......Page 205
Coasting with an H-Bridge......Page 206
Enumerating the Other H-Bridge Combinations......Page 207
Implementing the Classic Bipolar H-Bridge......Page 208
Interfacing a PNP via an NPN......Page 209
Selecting a Resistor Value for R5......Page 210
Implementing a PNP Single-Transistor Bipolar Motor Driver with an NPN Interface......Page 211
Finishing the Bipolar H-Bridge......Page 212
Choosing the 4427......Page 213
Interfacing the 4427 to the H-Bridge......Page 214
Selecting the 4427 or a Close Family Member......Page 215
Mastering Motor Control......Page 216
Introducing the N-Channel Power MOSFET Single-Transistor Motor-Driver Circuit......Page 217
Always Connecting the Gate of a MOSFET......Page 218
Implementing the N-Channel Power MOSFET Single-Transistor Motor-Driver Circuit......Page 219
Setting the Input High by Default with a Pull-Up Resistor......Page 221
Choosing a Value for a Pull-Up or Pull-Down Resistor......Page 222
Choosing Between No Resistor, a Pull-Up Resistor, or a Pull-Down Resistor......Page 224
Revising the N-Channel Power MOSFET Single-Transistor MotorDriver Circuit to Include a Pull-Down Resistor......Page 225
Introducing the P-Channel Power MOSFET Single-Transistor Motor-Driver Circuit......Page 226
Implementing the P-Channel Power MOSFET Single-Transistor Motor-Driver Circuit......Page 227
Introducing the Power MOSFET H-Bridge......Page 228
Implementing the Power MOSFET H-Bridge......Page 229
Interfacing to a Power MOSFET H-Bridge......Page 230
Selecting Power MOSFETs......Page 234
Reducing Switch Resistance Is Desirable......Page 235
Paralleling MOSFETs Decreases Resistance......Page 236
Contrasting Parallel MOSFET Transistors with Parallel Bipolar Transistors......Page 238
Dreaming of the Ideal......Page 239
Using the 4427-Family As a Stand-Alone Motor Driver......Page 240
Getting the Classic Bipolar H-Bridge on a Chip......Page 243
Introducing the MC33887: A Feature-Rich MOSFET H-Bridge Motor Driver......Page 245
Understanding the Pins......Page 247
Implementing the MC33887 H-Bridge Motor Driver......Page 249
Sensing Motor Current......Page 250
Evaluating Motor Drivers......Page 252
Evaluating Motor-Driver Voltage Output with a Very Light Load......Page 253
Evaluating Motor-Driver Voltage Output with a Moderate Load......Page 254
Evaluating Motor-Driver Efficiency with a Very Light Load......Page 255
Evaluating Motor-Driver Efficiency with a Moderate Load......Page 256
Summary......Page 257
Covers the Panasonic PNA4602M 38 kHz Infrared Detector; Covers the 74AC14 Bicolor LED Driver; Shows How to Select Infrared Emitt......Page 259
Detecting Modulated Infrared with a Popular Module, or, Another Reason to Hog the Remote Control......Page 260
Hooking Up the PNA4602M Photo IC......Page 261
Testing the PNA4602M Photo IC......Page 262
Looking Even More Closely to See the Detection Delay......Page 263
Adding a 74AC14 Inverter Chip to Drive the LED......Page 264
Showing Both Detect and No-Detect States with a Bicolor LED......Page 265
Examining the Complete Reflector Detector Schematic......Page 268
Emitting the 38 kHz Wave......Page 269
Selecting an Infrared LED for the PNA4602M......Page 270
Selecting Trimpots for R7 and R6......Page 272
Selecting Capacitors......Page 274
Making It Work......Page 277
Selecting Halfway Between the Start of Detection and End of Detection......Page 279
Always Indicating Detection Suggests Signal Leakage......Page 280
Using an Oscilloscope......Page 283
Revealing the Purpose of a Schmitt-Trigger Inverter......Page 284
Targeting Reasonable Frequency Accuracy......Page 285
Accepting the Limited Accuracy and Stability of the Oscillator Circuit......Page 286
Failing to Detect Certain Kinds of Objects......Page 287
Failing to Detect Objects Far Away or Really, Really Close......Page 288
Analyzing the Distance Results......Page 289
Failing to Provide a Range Value......Page 291
Getting Ready for a Practical Robot Application......Page 292
Build the Mindless Room Explorer, Connect Modules, Control with a Logic Chip, Reuse Sandwich, Build Body-Part Templates, Use Spa......Page 293
Viewing Roundabout from the Sides......Page 294
Viewing Roundabout from Above and Beneath......Page 295
Roundabout’s Circuitry......Page 296
Controlling Direction with Simple Logic......Page 297
Turning Left and Turning Right......Page 298
Gradually Heading Left and Gradually Heading Right......Page 299
Avoiding Infrared Leaks......Page 300
Declaring Caveats Because of Gearmotor Availability......Page 301
Using Precision Escap Gearmotors in Roundabout......Page 302
Leaning Toward Particular Attributes......Page 303
Creating a Template......Page 304
Printing a Template......Page 305
Squaring the Template with the Workpiece......Page 306
Punching Holes for Better Centering......Page 307
Removing Tape Before Machining Sides......Page 308
Milling or Purchasing a Disc......Page 309
Examining Roundabout’s Motor Mechanism......Page 310
Using Matching Rectangular Motor Mounts......Page 311
Mounting Motors with Screws......Page 312
Centering Wheels with Idler Gears......Page 313
Slowing Down the Speed and Increasing the Torque......Page 314
Altering Speed and Torque with Pulleys Instead of Gears......Page 315
Reaching the Physical Limits of LEGO Moving Parts......Page 316
Defining Motor-Mount Dimensions......Page 317
Drilling All of the Motor Mounts at the Same Time......Page 318
Making Holes to Secure the Motor Mounts to the Center Platform......Page 323
Revealing the Finished Motor Mounts......Page 327
Summarizing Roundabout......Page 328
Setting All Controls to Safe or Moderate Positions......Page 329
Draining Power......Page 330
Getting Too High of a Resistance......Page 332
Watching Current Usage During Power-Up......Page 333
Fine-Tuning the Infrared Reflector Detector......Page 334
Testing the Sensors......Page 335
Encountering a Reversing Robot......Page 336
Encountering a Slow-Motion Robot......Page 337
Encountering a Rotating Robot......Page 338
Exercising All of the Robot’s Maneuvers......Page 339
Avoiding Toilet Paper Alley......Page 340
Switching to Blocks of Wood......Page 341
Ringing Around the Robot......Page 342
Evaluating a Drunkard’s Walk......Page 343
Evaluating Roundabout’s Walk......Page 344
Attempting to Use a Resistor-Capacitor Circuit......Page 345
Attempting to Use High-Beam Hysteresis......Page 347
Running Out of Simple Ideas......Page 350
Considering the Atmel ATtiny84 Microcontroller As an Example......Page 353
Choosing a Logic Chip Over a Microcontroller......Page 354
Choosing a Microcontroller Over a Logic Chip......Page 355
Storing Programs......Page 356
Writing Programs......Page 357
Debugging the Program......Page 358
Lighting Up an LED......Page 359
Creating a Heartbeat......Page 361
Driving a Display......Page 362
Microcontroller Packages......Page 364
Input Pins......Page 365
Output Pins......Page 367
Microcontroller Memory......Page 370
Supplementing with External Nonvolatile Memory......Page 371
Volatile Memory......Page 372
Microcontroller Speed......Page 373
Generating a Clock Signal......Page 374
Using the Clock As a Timer......Page 376
Low-Voltage Watchdog......Page 377
Running Out Of . . .......Page 378
Recommending the Parallax BASIC Stamp......Page 379
Graduating Your Robot......Page 381
Covers Connecting Two Parallel Circuit Boards, Using Machine-Pin Sockets, Selecting Screws, Reheating Solder Joints, Interceptin......Page 383
Converting to a Two-Story Configuration......Page 384
Connecting to the DIP Socket......Page 385
Using Machine-Pin Sockets and Headers......Page 388
Securing the Daughterboard to the Motherboard......Page 389
Soldering the Headers......Page 391
Soldering the New DIP Socket......Page 394
Perilously Stacking Sockets......Page 396
Shading the Infrared Reflector Detectors......Page 397
Intercepting Signals: Meeting the New Boss......Page 398
Rerouting the Infrared Detection Signals......Page 399
Producing (Almost) Complete Control......Page 400
Powering the Microcontroller......Page 401
Controlling the Bipolar LEDs......Page 402
Debouncing an Input......Page 403
Providing Options with a DIP Switch......Page 404
Avoiding Intermittent Switch Changes......Page 406
Remaining Pins Available for Expansion......Page 407
Upgrading a Robot......Page 408
Sensing Brightness with Photoresistors......Page 409
Converting Varying Resistance into Varying Voltage Through a Voltage Divider......Page 411
Selecting a Resistor for the Voltage Divider......Page 412
Photoresistor Response Is Nonlinear......Page 413
Calculating Any Resistance for a Given Illuminance......Page 415
Testing Variance......Page 416
Rising and Falling Resistance Speeds......Page 417
Sensing Brightness with a Photodiode IC......Page 418
Presenting the Floor Reflectivity Circuit......Page 419
Implementing the Floor Reflectivity Circuit......Page 420
Cutting Out a Semicircular Breadboard......Page 421
Baffling the Board......Page 422
Putting on a Black Skirt......Page 423
Gutting a LEGO Brick......Page 424
Tuning and Testing the Floor Reflectivity Circuit......Page 425
Testing on a Minimally Reflective Surface......Page 426
Autodetection of Line Brightness......Page 427
Inverting Sensor Values......Page 428
Improving the Line-Following Algorithm......Page 429
Entering Roundabout in Robot Sumo......Page 430
Expanding Possibilities......Page 431
Presenting the Audio Circuit......Page 433
Listening to Binary......Page 434
Selecting a Speaker......Page 435
Seeing Sound......Page 436
Playing a Tune......Page 437
Playing Tunes Simultaneous to Robot Action......Page 438
Creating a Double Platform......Page 439
Providing Greater Headroom with Homemade Spacers......Page 440
Wheel Slots......Page 441
Supporting Both Ends of the Axle......Page 442
Mounting with Angle Stock......Page 443
Purchasing Aluminum Angle Stock......Page 444
Drilling Holes with a Template......Page 445
Purposely Incorporating Wiggle Room by Drilling Unthreaded Oversized Holes......Page 446
Notching and Grooving......Page 447
Placing the Drive Train into the Robot’s Body......Page 448
Adapting a Small-Diameter Motor Shaft and Integrated Mount for LEGO Compatibility......Page 449
Altering the Gearmotor Shaft......Page 450
Adding Tubing......Page 451
Attaching the Motor with a Peg-Based Mount......Page 452
Roaming the Solar Terrain......Page 453
Selecting Wheels for a Smooth Ride......Page 454
Looking for Light and Sensing Shadows......Page 455
Using Spring Tubing......Page 456
Lever Switches......Page 457
Adding a Wireless Video Camera to Any Existing Robot......Page 459
Exploring Yourself with Wireless Video......Page 460
Thank You......Page 461
Internet References......Page 463
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C......Page 468
D......Page 469
G......Page 470
H......Page 471
L......Page 472
M......Page 473
O......Page 474
P......Page 475
R......Page 477
S......Page 478
V......Page 480
W Z......Page 481