Introduction to the ME2110 Kit. Controller Box Electro Mechanical Actuators & Sensors Pneumatics

Transcription

1 Introduction to the ME2110 Kit Controller Box Electro Mechanical Actuators & Sensors Pneumatics

2 Features of the Controller Box BASIC Stamp II-SX microcontroller Interfaces with various external devices Stepper Motors DC Motors Pneumatic Valves IR Distance Sensor Flex Sensor Microswitches Solenoids RS-232 Communication Port

3 P11 P12 P14 P13 P15 Outputs RF / RS-232 Selector Motor_1 P9 - Speaker ID Reset Motor_2 P7 - Start Battery Charger RS-232 Connector On / Off Switch Inputs P6 P5 P4 P3 P8 P1 Layout of I/O Ports

4 Connections Interfacing the BASIC Stamp P1: Flex Sensor P3-P6: Microswitches P7: Microswitch that will be used to start competition P8: Distance Sensor P9: Speaker P11-P15: Solenoids, DC Motors Large Plugs: Stepper Motors RF / RS-232 Selector P9 - Speaker P7 - Start RS-232 Connector P11 P12 P14 P13 P15 ID Reset P6 P5 P4 P8 P3 P1 Motor_1 Motor_2 Battery Charger On / Off Sw itc h

5 Electro/Mechanical Supplies

6 Microswitches Lever arm closes circuit Status of IN register holds status of port 0 = Open Circuit 1 = Closed Circuit Same action is going to start competition

7 Solenoids Consists of a coil of wire Electromagnet When powered up, pulls in plunger.

8 Speed is proportional to voltage Moves in one direction Gearbox to slow down shaft Very high torque Requires time to ramp up and down. DC Motors

9 DC Brush Motor Fixed Field Magnet Coils create an electromagnet Field magnet rotates armature As armature turns, polarity reverses Cycle continues.

10 Pulse Width Modulation (PWM) Controller box can only send 0 or 5 volts PWM is used to run motor at intermediate speeds PWM uses cycles of pulses. 5 Volts 0 Volts Off On One Cycle

11 Both motors are controlled through P10 Speed is a value chosen between 2 and 240 Can move both directions Negligible ramping time Low Power Stepper Motors

12 Stepper Motor Clockwise Rotation Reverse Process for Counterclockwise Rotation

13 Detects deflection Works like a strain gage Flex Sensor Resistance changes with deflection Voltage reading sent through A/D converter 12-bit output (0 4095)

14 4 to 31 Range Infrared Distance Sensor Infrared beam is emitted Beam reflects off object Detected by receiver Output voltage proportional to distance A/D Converter: Reading between 0 and 255.

15 A/D Converter Converts a continuous voltage to a multi-level discrete digital value Used with: Distance Sensor (0-255) Flex Sensor (0-4095) Use these values to convert to desired quantities using conversion factors.

16 A/D Converter

17 Power up chip Using the A/D Converter Choose channel Serially send a Take Reading command Serially receive the value Power down chip

18 Programming the Stamp PBASIC (a version of BASIC) is used to program the Stamp Everything is global Variables Constants Subroutines Programming and commenting style is very important Programming syntax is explained in the manual.

19 Programming Editor Save Run Motor 1 Read Flex Sensor Release Alien Whacker Grab Viruses Transfer Humans to Safety Transfer to Controller Box

20 Program Structure Constants Table Constants are substituted at compile time Variable declaration Reserves portions of the Stamp s limited memory Main program loop Subroutines Often much of the work is done in subroutines

21 Variables Variables are memory reservations on the BASIC Stamp Variables must be declared before they can be used Variable types are: Word (16 bits): Byte (8 bits): Nibble (4 bits): 0-7 Bit: 0-1

22 Bytes, Nibbles, and Bits 1 byte = 2 nibbles = 8 bits: High Nibble Low Nibble B7 B6 B5 B4 B3 B2 B1 B0 Most Significant Bit (MSB) Least Significant Bit (LSB)

23 Words and Bytes 1 word = 2 bytes = 4 nibbles = 16 bits: High Byte Low Byte Word

24 Selected Commands Branching If Then Goto GoSub Return Looping For Next Debugging Debug Sounds (Music) Freqout DC Motor Control PWM Digital I/O Input, Output High, Low Serial I/O Serout Shiftin, Shiftout Time Pause Power Management End

25 Best Way to Learn is to Do Read through the manual Examine the sample programs and program fragments Studio assignment Ask questions Additional Information (BASIC Stamp)

26 Pneumatic Supplies

27 Pressurized Extension Spring Return 2.5 in Stroke Pneumatic Actuator

28 Pressure Vessel Pressurize with Bike Pump Max 100 psi Supplies Actuator strokes

29 Pneumatic Valve

30 Machining Studio Goals: Learn to Respect Machine Tools Learn to Cut Gain Experience Generate Design Ideas Build Confidence Preserve Digits

31 The Coupler 1/2-20 UNF 6-32 UNC THRU φ DP ± 1/ All tolerances ±0.010 unless otherwise specified

32 The Lathe

33 The Bracket

34 The Mill