• • • • • A CNC Machine that can be used not only by manufacturers but also by small scale hobbyists at costs much less than competitors. Three forms of communication either through serial port, Ethernet, or USB jump drive Controllable through a specially designed hand pendant Multiple tool heads for different applications including milling, paste dispensing, and air brushing Able to move at high speeds with longer working life compared to other relative machines • • Other machines perform only one specific task Loading different programs by current methods result in longer machine down times and loss in revenue.

Base X Axis Y Axis Z Axis

Base Y Axis

Table Specifications:

• Table Work Area: 1160 in 2 • Maximum Part Weight: +18 lbs • Table Supported by Rail: 0.375 in x 1 in

Y-Axis Rail Design:

• Length: 38 in • Weight Supported: 40 lbs • Length and Weight was significant • Guide system selected: Supported rail

Designed Considerations:

• 5.5 lb cutting force • 10 lb tool head • 100 lb.in moment due to weight • 75 lb.in moment due to cutting force

Design Specifications:

• X-Rod Diameter: 1.18 in (30mm) • Rod Spacing: 4 in • Supports 37.8 lbs/rod • Maximum deflection: 0.001 in

System Loads:

• 26.70 lbs, 15.63 lbs, 22.53 lbs

Alternative Design:

• 4 Rods with 15.63 lbs/rod • Rod Diameter : 1 in • Cost increases X Axis

Rod 1: 26.70

x

Rod 2: 15.63

Rod 3: 22.53

y

Z-Axis Design Considerations:

• Minimize moment about x-axis ballscrew • Guide system selected: Versa rails • Moves tool head closer to center of x-axis

Alternative Design:

• 2 Guide Rods • Increases moment Z Axis

Ballscrew Drive Specifications:

• Lead: 0.2 in/rev • Diameter: 5/8 in • Supports: Ball bearing & Thrust bearing block assembly

Thrust Forces:

• Acceleration 28.9 lbs -Static friction and acceleration force • Constant Velocity 18.8 lbs -Only kinetic friction

Tool Head Options:

• Spindle • Paste dispenser

Motor Drive Assembly

•

Purpose: Power Motors to drive ballscrews, providing motion in 3 dimensions

Motor Design Requirements

• •

Provide a minimum 20oz.in of torque at a speed of 4 in/sec. Required to move each axis.

Be cable of providing a minimum torque safety factor of 100%.

Motor Specifications

• •

Motor sizes: 276 oz.in (X-axis & Y-axis) 166 oz.in (Z-axis)

• •

Motor Requirements: 2.8 amps/phase Voltage of approx. 48 volts for a torque of 80oz.in at 4in/sec.

Motor Driver Considerations

• • •

Requirements: step and direction inputs to move motors Cable of driving motors at a minimum of 2.8 amps.

Surface mount chips to save space.

•

Selected: Allegro A3986 [micro-stepping sequencer]

Motor Driver Considerations

• •

Other design requirements Low power dissipation: Mosfet H-Bridge with very low on resistance. (.050 ohm) Current sense resistor: very low resistance (.043 ohms)

• Traces :2 oz vs. 1 oz copper. – To Provide low trace inductance to reduce high voltage spikes from destroying chips. Provide low power dissipation for motor traces.

• Power Transformer selection: provide power to motors that would fit into small cabinet with minimum stray magnet fields.

•

System monitoring and fault

identification: fuses and LEDs added to aid trouble shooting and protect circuit

Features • Pulse width modulation, MOSFET H-Bridge • Motor size from 2 to 4.7 amps • Optical Isolation for all inputs • Full, Half, 1/4, 1/16 step resolution • Over Current Protection • Over temperature and under voltage protection • Fuse Blown Indicators (3 LED’s) • 5 V supply Good LED • Outputs to Controller • Drive Board Ready Signal • Drive Board Fault Signal • Motor Power Supply Ready Signal

24 Vdc +-12 Vdc +5 Vdc Low Voltage Power Supply Block Diagram Motor Driver Board To Controller Vref X,Y,Z axis Step Direction Enable Reset MS1, MS2 Logic Inputs From Controller Optical Isolation Micro stepping Sequencer PFD1, PFD2, SR (jumper selectable MOSFET H-Bridge A+ A B+ B Connections to Bipolar Stepper Motors X,Y,Z axis Vm+ Vm Motor Power Supply 12 V Fuse Blown -12 V Fuse Blown 24 V Fuse Blown LED Indicators 5 V GOOD Driver Board Ready Vbb Ready Driver Board Fault Output Signals System Monitoring and Fault Identification To Controller

• Ethernet Microprocessor • ENC624J600 (Microchip Technology) • Communication Controller • PIC24FJ256GB110 (Microchip Technology) • Motion Controller • PIC24HJ256GP610 (Microchip Technology) PIC24HJ256GP610 PIC24FJ256GB110 ENC624J600

24 bit 100 pin micro-processor is used to control the communications for the CNC.

Any data that comes into the the Controller board goes thorough the Communication micro controller. Specific requirements: 1 – SPI 2 – UART 8 – Data Pins 16 – Address Pins

Features

Operating Frequency Program Memory(Bytes) Program Memory(Instructions) Data Memory(Bytes) Interrupt Sources I/0 Ports Total I/O Pins Remappable Pins

PIC24FJ256GB110

DC - 32MHz 256K 87,552 16,384 66 A, B, C, D, E, F, G 83 44 Connections to the Com controller: • • • RS232 Serial • USB to Go • Ethernet VGA(Output) Total Number (16-bit) 32-Bit (from paired 16-bit timers) Input Capture Channels Output Compare/PWM Channels 5 2 g g Input Change Notification Interrupt

Serial Communications:

81 ------------------------ UART 4 SPI IC Parallel Communications JTAG Boundary Scan/Programming 3 3 Yes Yes 10-Bit Analog-to-Digital Module Analog Comparators CTMU Interface Resets Instruction Set Packages 16 3 Yes POR,BOR,Reset inst 76 base inst 100-pin

64 pin micro-controller specifically for Ethernet implementation.

No programming was needed for this chip. It comes pre-configured to take Ethernet data. This micro chip connects directly to the Com Controller Specific Requirements: 1 – SPI External Connections: • RJ45 Connector

Features

Pin Count Ethernet Operating speed Ethernet Duplex Modes Ethernet Flow Control Buffer Memory Internal Interrupt Sources Serial Host Interface(SPI) Parallel Host Interface Cryptographic Security Options Receive Filter Options Packages

ENC624J600

64 10/11 Mbps Half and Full Pause and Backpressure 24K 11 Yes 8 Yes Accept or Reject packests with CRC 61-pin TQfP

24 bit micro-controller used to take the data from the communication micro chip and distribute Data to the motor driver board.

Specific Requirements: 2 – SPI (to communication) 1 – UART (to Pendent) 8 – Data Input Pins 4 – External Interrupts

Features

Pins Flash Memory Ram DMA Channels Timer 16 bit input Capture Output Compare Std. PWM Codec Interface ADC UART SPI IC CAN I/O Pins(Max)

PIC24HJ256GP610

100 256 16 8 9 8 8 0 2ADC 32 ch 2 2 2 2 85

2 MAIN CONTROLLER BOARD 3 5 15 13 11 7 9 X_S X_D Y_S Y_D Z_S Z_D OE OR OM1 OM2 J4 1 3 5 7 9 11 13 15 17 19 X_S – X-STEP X_D – X-DIR Y_S – Y-STEP Y_D – Y-DIR Z_S – Z-STEP Z_D – Z-DIR OE – OUTPUT ENABLE OR – OUTPUT RESET OM1 – OUTPUT MICROSTEPPING OM2 – OUTPUT MICROSTEPPING J1 1 3 5 7 9 11 13 15 17 19 1 PENDENT 4 6 8 10 12 14 16 MOTOR DRIVER BOARD 1 – J1 SERIAL PORT: P 2 – J2 SERIAL PORT: MC 3 – TB6 PIN 3: MC 4 – J11 PIN 1: DB 5 – TB6 PIN 4: MC 6 – J11 PIN 2: DB 7 – J4 PARALELL PORT : MC 8 – J1 PARALELL PORT : DB 9 – TB7 PIN 1: MC 10 – J10 PIN 1: DB 11 – TB7 PIN 2: MC 12 – J10 PIN 2 : DB 13 – TB7 PIN 3: MC 14 – J9 PIN 1 : DB 15 – TB7 PIN 4 : MC 16 – J9 PIN 2 : DB DB- MOTOR DRIVER BOARD MC – MAIN CONTROLLER BOARD P - PENDENT

Case

X: Y: Z: A:

Screen

-50 50 JOG

•

Requirements

– LCD Screen – Four buttons for accessing different function screens, accepting a command, canceling a command, and switching the axis between y and z on up and down directional buttons – Four buttons to change direction on x, y, or z axes – Feed pot dial to increase or decrease feed/speed rates

•

Casing

– Upper section will have a width of 5 inches and a length of around 2.5 inches • Placement for LCD Screen, Function button, Accept Button, Cancel Button, Axis Switch Button, and Feed Pot Override – Lower section will have a width 3 inches and a length of 3.5 inches • Placement for X, Y, and Z directional buttons

•

System Diagram

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LCD Screen

–

PIC 24 Microcontroller

–

DB9 and MAX32

•

Receive and transmit information from main controller system to pendant system

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Voltage Regulator

•

Input of 5 volts to make controlled output of 3.3 volts

–

Feed pot/Potentiometer

•

Control of feed/speed rate

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Clock chip

•

Steady, constant flow of information

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Switch buttons

•

PCB Layout

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Top Layer

•

LCD Screen

•

Top four buttons are function, accept, cancel, and axis switch

•

Bottom four buttons are four axis direction movement

–

Left and right control x axis

–

Top and bottom control y or z axes

–

Bottom Layer

• •

Remaining Components Tightly packed to prevent losses

•

Connector at bottom to attach to main controller system

•

Screens

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Main Screen

•

Upper left box contains current x, y, z, and acceleration axes

•

Lower left box contains circles for limit switches which will either be red/green to show on/off

•

Upper right box contains current adjustment of feed pot ranging from + 50 % of the rated value

•

Lower right box displays the current state of the machine which can be jog, idle, or run

–

Other Screens

•

All Sub Screens

•

Offsets Screens- Home, Park, Work Offset 1, Work Offset 2

•

Soft Limits Screens- Upper and Lower

•

Parameters Screens- Machine Parameters, TCP/IP Configuration, Communications Port

•

Flash Drive Screen

X: Y: Z: A: -50 50 JOG

Mechanical Total $ 2,406.89

Electrical Total $ 779.76

Grand Total $ 3,186.65

The Mechanical Total comprises of: • Frame • Bolts • Ballscrews • Rods • Shafts The Electrical Total comprises of: • Circuit Chips • Driver Boards • Controller Boards • Pendent

4 5 6 7 2 3 Step # 1 Step Description Place parts on boards Table Assembly Gantry Assembly Tapping and Drilling Electric Box Assembly Assemble Systems Testing Total Hours 4 5 13 8 69 Hours 4 20 15 Each component requires different time frames to finish each subassembly. The construction is simple once all subassemblies are finished, and the machine can be fully assembled in a 4 hour period with a three man team. The machine is ready for operation after testing is complete.

Dr. Haibo Wang- Faculty Technical Advisor Mr. Mark Hopkins- Technician/ Field Engineer for Allegro Micro-devices Mr. Howard Everton- President of Norva Plastics Barb Saathoff- Representative from Dytronix Tim Attig- Mechanical Shop Machinist