MTConnect CHALLENGE I WIDE AREA PRODUCTION SYSTEM (WAPS)

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Oct 18, 2013 (3 years and 9 months ago)

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1


Letters 2012
MTC ver 5 28 3 04

PM 2013
.3










MTConnect CHALLENGE I





WIDE AREA PRODUCTION SYSTEM
(
WAPS
)





Ilmar Luik


Manager of

Teaching Factory, Inc.


169 Bolling Rd.

Meridianville, Al 35759



ilmar@teachingfactory.org





Phone: 256
-
828
-
5789





May 31

2013









2


1.
ABSTRACT


The
Wide Area Production System

(WAPS) combines MTConnect compatible

Manufacturing
Intelligence S
oftware

(MIS) with manufacturing machines and equipment of all kinds that are
equipped with MTConnect standards compliant data interfaces to interact with innovative
machine vision optics, low
-
cost pallets, and pallet transport systems to form a robust and mostly

24/7 unattended production control and monitoring system.


WAPS implements MTConnect standards in a manner that is innovative, achievable, practical,
and measurable. It is an open system that provides all standard MTConnect functions such as
data collecti
on, formatting for easy interpretation by all decision makers, manufacturing support
services, maintenance, logistics scheduling, administration, etc.


WAPS is up scalable, virtually without limits, by adding MTConnect standards compliant
machines and plug
-
and
-
play hardware and software modules from all qualified vendors.


For quality control, WAPS performs Coordinate Measuring Machine (CMM) style checking of
part dimensions with
The National Institute of Standards and Technology (
NIST) traceable accuracy
b
efore they are removed from the machine.


WAPS is affordable for small enterprises by starting with a few legacy machines that have been
retrofitted with MTConnect standards compliant interfaces and a core of MIS.


2.


PROPOSED IDEA

2.1


Goal

The
immediate g
oal

for
Wide Area Production System
(WAPS) is to provide a low
-
cost, readily
implementable time and labor saving manufacturing system for machine shops of all sizes. The
ultimate goal is to enable small
-

and medium
-
sized United States (U.S.) man
ufacturing
enterprises to produce a wide variety of complicated precision parts and assemblies that are made
of all common materials for a lower total cost than any competitor anywhere in the world. This
of vital interest to Department of Defense (DoD).


2
.2


Su
m
mary D
escription of the Proposed Idea

The core of the
WAPS is MTConnect compatible
Manufacturing Intelligence S
oftware
(MIS)
that enables metal
-
cutting and assembly machines that are equipped with MTConnect standards
compliant data interfaces

to in
teract with innovative machine vision optics, low
-
cost pallets, and
pallet transport systems to form a robust and mostly 24/7
mostly
unattended production system
.


2.3

Detailed Description

of the Proposed Ideas

Implementation of WAPS became practical an
d cost effective with the development of the
innovative
Computer Numeric C
ontrol
(CNC) Setup H
elper machine vision optics by the
Teaching Factory, Inc. It is distributed by NEXAS Networks, Inc.
under the trade name of
TooliVsion
. I
t

has been proven to measure part dimensions and its location on the CNC machine
table with a ±
0 .0001 in. accuracy. NEXAS’ ORi
ON computer provides it with Optical Pattern
Recognition Software (OPRS) and MTConnect standards compliant data interfaces to MIS
.



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2.4


First Innovatio
n

The first innovation eliminates the need for precision fixtures and stops.


Parts to be machined or assembled
need to be firmly attached
to the pallet and pallet to the
machine table but neither needs to be precisely located.

The

combined location accuracy of
about ± 0.25 in from the intended location is sufficient.


That is a disruptive idea. All traditional manufacturing practices require precise locating

and firm

attachment of

parts

and pallets

to the machine table.

It is norma
lly done with the aid of fixtures
and locating pins. It is a very costly and time consuming part of traditional machining practices
and, in most cases, reliable automation of that process is cost prohibitive.


Elimination of the need for extreme placement
accuracy enables WAPS to use low
-
cost flame
cut and Blanchard grinded iron plates for pallets and low
-
cost magnetic chucks for

firm
attachment of the

pallet
s to the machine table. Neither needs to be designed or built to provide
extreme locating accuracy.

This leads to a drastic redu
ction of the WAPS procurement

cost.


For additional cost savings, WAPS can be programmed to produce its own standard and
customized pallets. In WAPS, the pal
let can be the work piece
.


2.5

Second Innovation


A second disruptive idea is that a CNC machine’s coordinate system is moved to the precise
registration with the coordinate system of the part to be machined or assembled.


Traditional CNC machining requires precise location
and firm attachment
of the
part to the
machine table before m
achining begins.


In WAPS, the precise location of a part on the machine table is not critical because its precise
location is determined with the aid of the NEXAS Tool
iVision

and the associated Optical Pattern
Recognition

Software (OPRS) with a ± 0.0001 in accuracy after it has been firmly attached to the
pallet and
the

pallet has been firmly attached to the
machine table.


NEXAS TooliVision

contains a TV camera that is precisely centered on the rotation axis of the
CNC s
pindle. The output of the camera is fed to OPRS

that resides inside the M
TConnect
standards compliant ORi
ON computer
that is programmed to recognize predetermined reference
features of the part to be machined
(e.g., its lower left corner).


The outputs fro
m the OPRS
are used to move the CNC mac
hine table to locate the part’s

lower
left corner to the position that is directly under the center of the spindle rotation. The same
process is repeated for the opposite corner of the part

to be machined. That proces
s determines
the exact location of the part on the machine table with a ± 0.0001 in accuracy in the CNC
coordinate system.


Next, b
y invoking G68 (Coordinate System Rotation On) and G69 (Coordinate System Rotation
Off), the

CNC
machine coordinates are tran
slated and rotated into registration with the

4


coordinates of the part to be machined. The

Tool
iVision

is then returned to the
tool magazine
and the machining cycle is started.

The above described location process is also applicable for locat
ing a part for

a robot
assembly.
The
only

difference is that the TooliVision

is inserted into the robot’s end effector.


Note: In both cases, the location of the part or assembly is determined by directly imaging its
location with reference to the known location of the

centerline of the spindle. WAPS does not
care how accurately the par
t is located on the pallet or

how accurately the pallet is located on the
machine table. The only accuracy requirement

is that the
reference feature of the part must be
placed within
the
preprogrammed NEXAS TooliVision

search area.


The failure of the CNC X
-

and Y
-
axes

servos to position a predetermined feature of a part to the
location that is directly under the center of the spindle rotation within a predetermined time limit
is immediate
ly detected by the O
PRS and the ensuing alarm triggers a corrective
action.


This feature
ensures that WAPS will not produce scrap
.

T
he immediate call to trigger corrective
action is a great product
ion cost and time saver. WAPS can also be

programmed to diagnose the
problem and initiate

specific corrective action. For example:




If a failure is caused by a target CNC failure, the WAPS commands the cart to pick up
the pallet and carry it to another CNC that is, or will be, progr
ammed to finis
h the same
part.




If a failure is caused by the wrong part being on the pallet or its position

is far out of
limits, then WAP
S

will return the pallet to the
central pallet
loading
area (CPLA) and tag
it as a REJECT.


2.6


Third
Innovation

This innovation
eliminates the need for a pallet loader at each machine.


Parts are installed on the pallets at the CPLA. From this area, the pallets are transported to the
target CNC machines on an autonomous pallet cart (APC).



After machining is completed, the APC ret
urns pallets with finished parts to the CPLA. This
eliminates the need for expansive and floor
-
space wasting pallet loading/unloading equipment at
each production machine or even a more expensive precision pallet transport rail system.


The CPLA is the
only area in WAPS that requires operating personnel. In all other areas, the use
of manned production stations is optional if its unattended operation is not cost effective. Also,
the CPLA needs to be manned only for one shift to load and unload the parts.


The main component of the CPLA is a relatively low
-
cost conveyor; its length determining how
long WAPS can operate unattended.





5


2.7


Fourth Innovation

Parts are inspected and measured with National Institute of Science and Technology (NIST)
traceable

accuracy before they are removed from the machine.


This is not a totally unique feature of WAPS. Many automated metal
-
cutting and assembly
machines can do the same but WAPS, with the aid of MTConnect standards, makes it practical
and affordable for small
-

and medium
-
size machine shops at no additional cost. This is possible
because NEXAS’ Tool
-
Eye can be programmed to perform all programmable CMM functions
.


2.8


WAPS
Manu
facturing Intelligence Software

The software side of WAPS is its

MIS that is und
er development at the Teaching Factory, Inc. It
will comply with all MTConnect software standards. The first goal for the MIS architecture is to
accept MTConnect compliant plug
-
and
-
play modules from all qualified vendors, and the second
goal is to make MIS

easy to install, commission, and maintain by personnel with only
rudimentary computer skills.


2.9


BENEFIT TO INDUSTRY

WAPS enables skilled manufacturing employees to produce more than ever before. This is vital
for the survival of the U.S. because
skilled tradesmen are retiring faster than the U.S. education
system is able to replace them.


Unless small
-

and medium
-
sized manufacturers start operating mostly unattended, the DoD will
not be able to obtain high quality parts and assemblies in small lot
s for an affordable cost and on
time. In the next war, that is likely to cause lost battles and lives.


On the commercial side, WAPS enables the wide use of 24/7 lights

out manufacturing for greater
Return On I
nvestment (ROI). This alone accelerates expan
sion of the U.S. manufacturing
industry.


A major cost benefit is realized due to the fact that machines can operate largely unattended for
24/7. Without this capability, the ROI in a typical U.S. manufacturing plant is marginal and will
worsen as time go
es on. WAPS has a comparatively low
-
procurement cost as compared to other
automated production systems that depend on extremely expensive propriety pallets.


The DoD will benefit by being able to access a vibrant U.S. manufacturing industry that is
capable

of producing a wide variety of precision parts and assemblies in small lots for reasonable
prices with a fast turnaround
. WAPS makes this possible by creating a mostly automatic lights
out production system that is affordable for small
-

and medium
-
sized U
.S. manufacturing
enterprises.


A quality benefit is realized because WAPS includes an in
-
process traceable measuring function
that can be programmed to produce often required 100% quality control documentation.






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3. TECHNICAL REQUIREMENTS


3.1
Requirements for Implementation

Technical requirements for implementing WAPS are minimal. It can be implemented by
personnel with only rudimentary computer skills and a relatively low upfront investment.


Implementation of WAPS became practical and cost ef
fective with the development of the
innovative CNC setup helper and MTConnect interface standards compliant CNC setup helper
machine vision optics by the Teaching Factory, Inc.


3.2


Utilization of MTConne
ct S
tandards

WAPS cooperates with MIS using MTConn
ect standards to collect all shop floor data that is
made available to it via the MTConnect network.


It formats the data for easy interpolations by decision makers at all levels. It also includes a
production simulation module to enable the decision maker
s to test various “what if” scheduling
and logistics possibilities to squeeze maximum possible efficiency out of the production system.


MIS keeps continuous track of the use of all machines on the network and schedules preventive
maintenance events and ma
chine loadings to produce measurable indications of WAPS
economic benefits.


MIS is open software and therefore its functions can be expanded whenever new plug
-
and
-
play
modules and device drivers become available from any qualified vendor.


Typical exampl
es are interfaces to Enterprise Resource Planning (ERP) and to all conceivable
quality control and documentation programs.


3.3


No scientific and or Technical Limitations to Implementation

Neither technical nor scientific breakthroughs nor enhancements to the MTConnect standards are
needed for WAPS to achieve its stated performance goals.


Most import
ant components, notably TooliVision

optics, for implementing WAPS are already
available from

NEXAS Networks, Inc. More are in development stage.


3.4 Milestones

Some of the ideas which are expressed in this document are already commercialized.

Milestones have been established to commercialize all of them

in near future
.