A personal repository of random information in compensation for a fatigued biological computer
20110829
Full machine post conversion from DVD drive head actuators to pneumatic cylinders
Rear of machine
201108728
20110628 Upwards USB camera for head offset calibration
late 2010 images
20110908 - Improvement iteration complete
A minor change to allow calibrating PCB origins using a nominated PCB pad
20110829 - Improvement iteration complete
Hardware status:
20110824 - Improvement iteration complete
Hardware status:
20110728 - Improvement iteration complete
Hardware status:
Software status
20110605 - Improvement iteration complete
New Mach3 dialog (unpopulated):
Hardware status:
feeder banks on right & left
USB camera mounted on gantry with heads downward looking for manually setting
left feeder bank origin
offsets of left feeder bank feeders from above
PCB origin per rotation
NEW USB camera looking up for calibrating head offsets from downward looking camera
Software status
This iteration is for major hardware redoing of the heads, primarily to facilitate adding 4 right side heads as well as improving existing 4 heads
Note: 4 x right side heads all electrically functional and Mach 3 macros for both z movement & vacuum toggling updated but not used as ran out of time to do Excel GCode generator changes
Hardware status:
8 heads on the machine:
4 left, 4 right
NEW control PCB for 8 x steppers
NEW 2 x 4 way mosfet switching boards for vacuum solenoids
NEW 8 automotive air solenoids (1 per head)
Remade all head spring U holders (better accuracy of drilling to reduce slop)
NEW 1 large vacuum pump
feeders on right & left
USB camera with heads downward looking for manually setting
left feeder bank origin
offsets of feeders from above
First PCB in an array origin
Software status
Excel generating GCODE for pick place operations using left 4 heads and left side feeder bank only
PCB arrays working fine
Hardware status
4 heads on the machine
fishtank vacuum pumps x 4 switched by solid state relays
feeders on right side only
USB camera downward looking moves with heads for manually setting
left feeder array origins
offsets of feeders from above
First PCB in an array origin
Software status
Excel generating GCODE for pick place operations using 4 heads and is doing PCB arrays ok
December 2010:
On this page:
Goal:
A low volume SMT Pick Place machine to place
Speed needs to be getting towards 1000 components an hour to be competitive with manual placement.
Note that there is no automated vision system. The machine simply follows a predefined sequence of instructions. The sucess of this approach depends on the accuracy and repeatibility of the machine.
This requires accurate calibration and for this purpose where-ever possible we use the web cam attached to the front head array to perform calibration of offsets.
Base functions required
A Pick and Place machine provides these base functions:
Initially we will address 1-4 above.
For 4 we will do for components supplied in 8mm tape only (initially)
For 5 we will rely on sufficient accurary of the machine to not address this in this phase of this project (But it is a current background task)
For 6 we will manually rotate an array of PCBs as necessary (The eventual solution for 5 may address this requirement also, but we may just rotate the PCBs automagically in the future)
Of the functions above, only 1 is provided by the stock CNC Router / Stepper controller PCB purchased on EBay.
We will use Mach 3 to control the machine.
We will use Mach 3 with GCode generated from a MS Excel spreadsheet.
Mach 3 communicates with the CNC machine via the parallel port. To enable us to provide functions 2-6 per above, we will breakout unused Parallel Port pins to our own interface PCB.
Physical layout
20110830
20101202 Changes per layout shown below..
X axis will move left to right for positive, Y axis will move up for positive. Camera location has changed as well to between the heads.
Hardware interconnections
20110910 As it will be after next change iteration (Finish converting all 8 heads to pneumatic)
20101230