Basic Electricity. Mike Koch Lead Mentor Muncie Delaware Robotics Team 1720 PhyXTGears. and Electronics. for FRC

Transcription

1 Basic Electricity and Electronics for FRC Mike Koch Lead Mentor Muncie Delaware Robotics Team 1720 PhyXTGears

2 The Quick Tour The Analog World Basic Electricity The Digital World Digital Logic The Rest of the World Microcontrollers

3 Forces Strong Force Holds nuclei together Electromagnetic Force Magnetism, light, electricity Attractive and repulsive Weak Force Holds electrons in orbit Gravitational Force Masses attract

4 Chapter I Basic Electricity Voltage Current Resistance

5 Characteristics by Analogy Potential - Voltage Depth of water behind a dam Flow - Current Water moving through the pipe Limitation Resistance Size of opening

6 Flavors anyone? DC Direct Current Batteries 1.5 VDC, 3 VDC, 12 VDC AC Alternating Current Commercial electric power 110 VAC, 220 VAC Static Electricity Potential Gradient Lighting

7 The Characters Voltage (E or V) the difference in potential Current (I) the intensity of the flow Resistance (Ω) the opposition to flow

8 The Characters Voltage (E or V) measured in Volts Current (I) measured in Amps Resistance (Ω) measured in OHMS

9 The Characters

10 Voltage

11 Current

12 Resistance

13 The Carriers/Blockers

14 The Rules OPEN circuit no current flow

15 The Rules SHORT circuit = HEAT SMOKE FIRE #1 Rule for SAFETY: KEEP THE SMOKE INSIDE

16 The Rules OHMS Law Voltage = Current * Resistance

17 The Rules OHMS Law Current = Voltage / Resistance

18 The Rules OHMS Law Resistance = Voltage / Current

19 A Practical Example How much current is flowing in this circuit?

20 A Practical Example How much current is flowing in this circuit?

21 A Practical Example How much current is flowing in this circuit? (30 Milliamps or mh)

22 The Other Rule POWER P = I X E Power = Current x Voltage Watts = Amps x Volts

23 The Other, Other Rule Capacity Capacity = Current * Time Amp-Hours AH

24 Batteries Direct Current Rated by Voltage Capacity 12 Volt -17 AmpHours Means: 1 Amp for 17 hours 17 Amps for 1 hour

25 Battery Tester Computerized Battery Analyzer Available from: West Mountain Radio Model CBA II $110

26 Battery Tester

27 The Tools VOM Volt Ohm Meter Multi Meter

28

29 Using the Multimeter to Measure Setting up the meter: Units: Ohms Range: High Connections: Ω RESISTANCE NEVER have a power source connected to a resistor when measuring resistance. This could blow the fuse in the meter.

30 Using the Multimeter to Measure Setting up the meter: Current Range: Higher than expected Units: A, Ma Connections: A or Ma

31 Using the Multimeter to Measure Voltage Setting up the meter: Range: Higher than expected Units: V Function: DC Connections: V+

32 Using the Multimeter to Measure Voltage Setting up the meter: Range: Higher than expected Units: V Function: DC Connections: V+

33 FIRST Electrical Layout A Circuit Breaker 12V SLA Battery 20A & 30A 40A Circuit Breakers Robot Controller Spike Relay Motor Controllers

34 Wire Selection and Layout Primary Batteries should last 2-4 matches There is resistance in every wire.001 ohm/ft #10 wire.0004 ohm/ft #6 wire There is resistance at every connection Resistance from wire and connections coupled with high current loads, places a voltage drop along circuit path

35 Example Drawing 116.4A (stall current of drill motors) over provided battery cables V = I*R V = 116.4A * (.0004 ohm/ft * 8 ft) V = 0.372V This does not include resistances from connections The total drop can be in excess of 0.5V!

36 Reducing Resistance Check every crimp Use the correct tool Solder critical joints Keep wires short

37 Analog vs. Digital

38 Analog vs. Digital Analog Voltage divider Digital Switch 4.5 V 0 or 5.5 V 0 or 5

39 The Digital World Logic Switches Relays Sensors

40 Digital Logic Logic Probe Indicates Binary Condition:

41 Digital Logic Two Conditions: Switch ON OFF Status Voltage High Low 5 V 0 V Boolean TRUE FALSE Binary 1 0

42 Switches Push Button Rocker Rotary Knife Toggle Micro Wall Decoder

43 Switches

44 Switches Light switch (3 way) Toggle switch

45 Switches Rocker Push-Pull Toggle

46 Switches Slide Toggle Micro

47 Switches SPDT

48 Relay A Switch controlled Electronically

49 Relay Control Automobile FRC

50 Relay Provides On or Off In either direction Full 12 VDC

51 Spike Relay Reverses the Output Voltage or Shorts the Output Used for constant speed motors or high load peripherals

52 Digital Sensors Produce DISCRETE state changes to indicate ENVIRONMENTAL change Voltage change from 0 to 5 volts Microswitch against a Cam O/P +5 0

53 Digital Sensors Limit Switch Speed Encoder Position Encoder Quadrature Encoder Optical Isolator

54 Digital Sensors Limit Switch wiring + 5 V

55 The Analog World Logic Switches Relays Sensors

56 Analog Sensors Output an ELECTRICAL change to indicate an ENVIRONMENTAL change Voltage, Current, Resistance or Capacitance IR Proximity sensor changes voltage with distance

57 Analog Sensors Position Potentiometer Photo Sensor Proximity- Ultrasonic, Infrared

58 Analog Sensors Voltage changes as Resistance changes

59 Multiple Output Sensors Camera Analog, I2C, SPI, PWM LiDAR Rangefinder I2C or PWM

60 Fuses Circuit Breakers Maxi Auto Reset Thermal delay 10 Sec at rating 3.9 Sec at 200%.6 Sec at 400% Thermal fuse

61 Power Distribution Panel (PDP) 8 x 40 amp fuses 8 x 5-30 amp fuses

62 Motor Controller Provides Variable Speed Direction For Motors

63 Logic Gates Buffer Output = Input

64 Logic Gates NOT (Inverter) Truth Table

65 AND Logic Gates

66 NAND Logic Gates

67 OR Logic Gates

68 NOR Logic Gates

69 Logic Gates D Latch Memory storage for 1 bit

70 The Micro Controller CPU Memory I/O Buses

71 Basic CPU Central Processing Unit

72 Memory RAM Random Access Memory ROM Read Only Memory PROM Programmable Read Only Memory EPROM Erasable Programmable Read Only Memory EEPROM Electrically Erasable Programmable Read only Memory

73 Random Access Memory Temporary Storage of Data Programs Context

74 Read Only Memory Permanent storage of Programs Data

75 A MicroProcessor has a few more devices...

76 I/O Ports External interfaces: Serial Port Parallel Port Digital I/O Analog I/O - Sensors Internal interfaces Hard Disk Video Display

77 Buses Address Data

78 CAN Bus Controller Area Network Daisy chain-bi-directional

79 CAN Bus CAN Bus wires MUST be Green and Yellow

80 RoboRio Computer

81

82 Analog Sensors

83 Switches Digital Sensors Encoders

84 Motor Controllers Servos

85 Spike Relays

86 Power Distribution Panel (PDP)

87 Voltage Regulator Module (VRM)

88 Pneumatic Control Module (PCM)

89 120 Amp Circuit Breaker On/Off Switch

90

91 Free Online Tutorials Basic Electricity Electronics Microcontrollers Wiring the 2017 FRC Control System Everything else