Gerber Technology XY cutter

1
Gerber Technology X-Y cutter

• Final Presentation
• ECE 290 December 11, 2002
• Team Members Sponsor Advisors
• Joshua Reinert (EE) Gerber Tech. John Ayers
• Michael Choi (EE) Bruce Plumley Bi Zhang
• Mark Grubin (CompE) Kevin Pearl
• Ryan Martin (ME) Alex Zusmanovich
• David Berry (ME)

2
Presentation Overview

• Introduction
• Physical Design
• Tool head
• Tool changer
• Tool bits
• Motors and Microcontroller
• Budget
• Conclusion and The Future

3
Our Project

• Creation of an automatic tool-bit changer for an
  X-Y materials cutter.
• Benefit of multiple bits being used without human
  intervention.
• Tool head can remain fast, light, efficient, and
  inexpensive

4
Starting point

• Gerber will supply us with a two-foot section of
  the control arm allowing for linear movement (and
  accuracy).
• Fitted with a mounting plate for a tool head.
• We must create the tool head, as well as the tool
  storage area.

5
Physical Design

• Tool head
• DC Motor (on right) causes raising and lowering
  of tool head to desired position.
• Tool head needs to be in only one of two
  positions, fully up, or fully down. Polarity of
  DC Motor will cause movement in desired direction
  until correct position is reached.
• Simple high-resistance catch will hold tool head
  in upward position while DC Motor is de-energized.

DC Motor
6
Physical Design, cont.

• Tool head, cont.
• 3.6 degrees/step Stepper Motor (mounted beneath
  tool head) controls angular rotation of tool bit.
  
• 201 stepdown gearbox attached beneath stepper
  motor, providing 0.18 degrees rotation per single
  step of motor.
• Solenoid attached beneath gearbox for attaching
  tool bits (discussed in following slides).

Stepper Motor
7
Physical Design, cont.

• Mechanism for attaching and releasing tool bits
• Cutting tool Hole puncher Notch Cutter

8
Physical Design, cont.

• Mechanism for attaching and releasing tool bits,
  cont.
• Each tool bit modified to be equipped with a
  carbon-steel attachment in which a solenoid can
  fit.
• As the solenoid (attached to the tool head) is
  energized, an electromagnetic field will draw and
  keep the tool attached to the tool head.
• When power is no longer running through the
  solenoid, the tool will release.

9
Physical Design, cont.

• Tool holder
• Holds up to 5 bits.
• Mounted on a belt, which allows movement back and
  forth along a single access.
• A stepper motor is programmed to move tool
  changer so the correct bit will be alligned under
  the tool head. (Tool head will always be at same
  location on this axis).

10
Physical Design, cont.

• Tool holder, cont.
• To prevent undesired rotation or slippage of
  bits, tool holder is keyed, and tool bits are
  modified accordingly.

11
Stepper Motor for Tool Head

• Bi-polar stepper, 3.6 degrees per step, 8.3
  oz/inch
• PIC generates two pulse width modulated signals
  90 degrees out of phase.
• These two signals are sent to the allegro 2916B,
  Dual H-bridge driver.
• The number of steps are controlled in software.

12
Stepper Motor for Tool Changer

• Bi-polar stepper, 1.8 degrees per step, 197
  oz./inch.
• Same concept as the tool head stepper, PIC will
  generate two PWM signals 90 degrees out of phase.
• The two PWM signals are inputs to Unitrode UC2950.

13
DC Motor to Lower Tool Head

• PIC generates a pulse width modulated signal,
  which the positive and negative duty cycle can be
  adjusted.
• This signal is then used as a input on the Dual
  high-speed power MOSFET Driver(microchip
  TC4427A).
• The duration in which the PWM signal is on will
  be controlled by timer 1.

14
Electrical Design - Motors
15
Budget

• Most Parts supplied by Gerber Technology or
• UConn Electrical and Mechanical Engineering
  departments
• Price Estimates
• Various Motors / Drivers / Switches 50.00
• PIC 16F874 microcontroller 7.00
• Kanetec KE-3E electromagnet 70.00
• Structural aluminum and steel 10.00
• Miscellaneous Materials 50.00
• Total Cost to reproduce project
  180.00
• Actual Cost (Total, less supplied parts) 60.00

16
Conclusion

• Project simplifies tool head, increasing
  efficiency and reducing cost
• Tool changer allows for simple modification to
  allow the addition of new tools
• Automation of tool changer allows the machine to
  operate without any input from a user

17
The Future

• Create simple state machine to run correct
  microcontroller code at correct time
• Convert to physical circuit and send out for
  creation of circuit board
• Integrate our board and motors with ME physical
  design.
• Attach keypad for simple user-interface
• DEBUG!!!