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licoricehealthAI and Robotics

Nov 14, 2013 (3 years and 7 months ago)

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A LOW
-
COST, EXPANDABLE, OPEN
-
ARCHITECTURE GRINDING
MACHINE CONTROL SYSTEM

John Moruzzi

AMTReL

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Director of Studies: Dr Michael Morgan

AMTReL

Jones & Shipman 1300X


Universal grinding machine


External and Internal
wheelheads


SAMM control (Servo Assisted Manual Machine)


Prototype machine based on Format 15 model


Built circa 1994, modified 2001


Closed control system


Industrial PC / MS
-
DOS

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Used for previous AMTReL projects/PhD’s


Adaptive control


(Y Chen)

Open CNC Interface


(C Statham)


High speed Internal grinding

Industry co
-
operations (Timken, Lucas, …)

Fluid delivery methods, nozzle design

AE monitoring

Dressing tool control (fluid coupling)

Aims of the project


Replace old ‘closed’ CNC control


New simplified operator panel


Touch screen operation


Implement existing cycles for External grinding


Enhance cycle programming and machine setup


Interface and integrate external process control equipment


Demonstrate optimised cycle



Modern software design and implementation


Expandable for intelligent and adaptive grinding features

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Initial Objectives

Machine

Familiarity with machine & electrics


Re
-
commission hardware


Move axes


Replace workhead drive


Modifications to wiring


Disable hardware limits


Remove original control panel


Control system

Initial “desktop” PC control :


ISA bus motion control card


No Digital I/O card


Standard mouse / keyboard / monitor


Initial Software


Windows 2000 (XP), Visual Basic


Programming familiarity


Axis configuration (Utility S/W)


Axis movements (Utility S/W, libraries)


Simple grinding cycles


Simple cycle parameters


No I/O features



A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Phase 2 Objectives

Machine


Modifications to hardware


Optimise axes (drives)


Replace original digital I/O wiring




Activation of



workhead



external wheel



coolant pump



Modifications to wiring

Enable hardware limits


Interface to original control panel

Interface external control devices (Power, AE)


Implement new control panel



Control system

New “industrial” PC control :


Rack mount case with Mini
-
ITX PC board


PCI bus motion control card


Digital I/O from motion card


Standard mouse / keyboard / monitor


LCD /
Touchscreen

monitor


Developed software


Windows XP, Visual Basic / .NET


Program design & implementation


Parameter definition & management


Enhanced axis moves (MPG)


Standard grinding cycles


Enhanced cycle programming


Initial IO features


RS232 connectivity

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Architecture of a CNC system

Main Control


Executor




Scheduling, program execution, monitoring

IO routines



HMI, programming, Digital, Bus

Safety




Machine logic

Cycle management


Sequencing, monitoring

Motion Control


Axis movements, motors


Process optimisation


In
-
process Gauging

Diameter, Shoulder

Touch Detection

AE, Power

Wheel balancing

Auto / Manual

Probing

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Adaptive / Intelligent Control


Adaptive strategy


Parameter modification

Selection strategy Rule / Case based

Process models & rules Kinematic, Compliance

Database



Learning strategy, data






New Components


Workhead

servo drive


Industrial PC


Motion control card


Touchscreen

monitor


Console switches / lamps


Cabling / connectors



A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Grinding Wheel speed and Control

Wheelspeed

Rotational speed


n
s

(RPM)


Surface speed

v
s

(m/sec)


Fixed on 1300X machine , can be changed with gearing / pulleys

(3 ratios)





Control buttons:

SB4

Start Wheel

Green




SB3

Stop Wheel

Red


Control relays:

KA5

Wheelhead Stop Override




KA12

Enable Internal Wheelhead




KA13

Enable External Wheelhead

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Workhead speed and control

Workspeed

Rotational speed

n
w

(RPM)



Surface speed

v
w

(m/sec)


Variable on most grinding machines


Controlled by operator / program

Open
-
loop motor drive control



3
rd

axis on motion card

Calibration





Reference Voltage => speed

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Control buttons
:

W+ W
-

Speed Down / Up




SB8

Start Workhead

Green




SB7

Stop Workhead

Red

Control relays:

KA4

Workhead Stop Override




KA6

Workhead Start Override




KA7

Workhead Stop Relay

Deva 004 : Axis servo setup


Z axis parameters




PITCH =
-
10.0000


MAXVOLT = 3000 (2150)

COUNT = 10000.0000

MAXSPEED = 60



MAXACCEL = 60



GAIN KV = 15

SPEED = 25


A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Motion card driver :

Set up and adjust axis configuration parameters in, to
match to real
-
world values and give satisfactory
response characteristics.


Optimization / minimization of lag and overshoot

Also :

Adjust servo drive amplifier settings, to give
satisfactory response characteristics.

Tuning of amplifier trim
-
pots

Optimization / minimization of drift and overshoot

Axor

MTS 400




VEL

Fine speed adjustment



Offset

Zero volt drift compensation

kV

Dynamic response (gain)

Der

Derivative

gain


Workhead drive setup #1

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Original drive unit
(with choke)

Original transformer
(single phase)


Non
-
standard drive and transformer (undocumented, unsupported)


Non
-
functioning

Workhead drive setup #2

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

New servo drive unit


New transformer

(3 phase 2kW)


Axor

drive
Masterspeed

MTS
-
200
-
14/28 and transformer TT2000/200
-
300


Matched to wheelhead motor SEM MT40
-
P4


Equivalent to Control Techniques Maxi
-
Maestro DCD 200 25/50

A

wheel power monitor

Motion Control Interfacing

Problem :

to integrate a new Motion card with the existing machine wiring.


Original ISA bus Motion card


4 axes on 2 boards:


Conn 1

15W D


Axis 0 encoder inputs


Conn 2

15W D


Axis 1 encoder inputs


Conn 3

9W D


Axis 0 , 1 servo outputs


Conn 4

15W D


Axis 3 encoder inputs


Conn 5

15W D


Axis 4 encoder inputs


Conn 6

9W D


Axis 2 , 3 servo outputs


New PCI bus Motion card


4 axes on 1 board + flyer cables:


Conn 1

15W D


Axis 0 encoder inputs / limit signals


Conn 2

15W D


Axis 1 encoder inputs / limit signals


Conn 3

15W D


Axis 2 encoder inputs / limit signals


Conn 4

15W D


Axis 3 encoder inputs / limit signals


IO2


25W D



Axis 0, 1, 2 , 3 servo outputs

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Digital I/O Interfacing

Problem:

To integrate a new Digital IO card with the existing machine.


Original ISA bus I/O card


48 opto
-
isolated signals on 50W D connector:


Conn 1

50W D


24 inputs, 24 Outputs, 2 x common


New PCI bus Motion card


48 opto
-
isolated signals on 2 flyer cables:


IO1


25W D




12 inputs, 9 Outputs, 2 x common, 1 x
WDog



IO2


25W D




4 inputs, 3 Outputs, 2 x common


Machine requirements:



16 Inputs, 7 Outputs, 1 x
WDog


Connection:



To terminal rails in electrical cabinet






To auxiliary control equipment

A Low
-
Cost, Expandable, Open
-
Architecture Grinding Machine Control System

Signal Interface Unit

To convert one set of signal configurations to be compatible with the machine wiring

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Servo 0, 1, 2, 3

Machine

Interface

Control PC

Servo 0 , 1

Servo 2 , 3

Outputs 0..11

Encoder 0

IO1 Inputs, Outputs

IO2 Inputs, Outputs

Encoder 1

Encoder 2

Encoder 3

Inputs 0..15

Encoder 0

Encoder 1

Encoder 2

Encoder 3

Additional

Additional

Signal Interface Unit cont...

Implemented as 2U high 19” rack enclosure

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Rack assembly with
connecting cables

Electrical cabinet :
-

I/O

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

I/O terminals

Fuses

Relay board

Control PC hardware

IEI Kino 945 GSE


Industrial Mini ITX board with Intel Atom
1.6GHz CPU (
Fanless
)


1 x PCI expansion slot


1 x 200pin DDR2 SODIMM slot


2 x SATA connectors, 1 x IDE


2 x RS232 ports on rear I/O


1 x RS232 port (internal)


1 x RS232/422/485 port (internal)


8
-
bit digital I/O

Further equipment


2U 19” rack PC case with PSU


Operating system Windows XP



8.4” LCD
Touchscreen

(VGA, RS232)



Deva 004 Motion card (4 axis + I/O)



2U 19” rack for signal interfacing


Blank 19” rack panels

Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Control PC hardware cont...

Front of 19” control console:



VM20 unit 3U (balance / touch)



Blank panel 1U



PC rack unit 2U



Signal Interface unit 2U

Inside of control console:



Axis cabling



I/O cabling



Cross connections

An Introduction to Grinding Machine Control Systems

Software panel


main screen

Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Main user interface

Z axis status
and Jog

X axis status
and Jog

Manual axis
control

Cycle start / stop
and status

Grinding mode
and program
control

Machine
functions
control

Software panel


program screen

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Cycle programming
-

Traverse

Common grinding cycles

Dressing


Single point “diamond” dressing:



Wheel rotating (surface speed
v
c

)



Wheel traverses past diamond tip (crossfeed velocity
v
f
)



Wheel
infeeds

an increment (infeed amount a
d
)



Repeat until wheel surface fully dressed

Plunge grinding

Workpiece

/ table positioned relative to wheel



Wheel and workpiece rotating (
v
c

and
v
w
)



Wheel infeed at Rapid speed to start position (
dia
)



Wheel infeed at Coarse feed to Fine Feed start position (
dia
)



Wheel infeed at Fine feed to Final Size position (
dia
)



Sparkout

or Dwell with no infeed

Traverse grinding

Workpiece / table set to oscillate across wheel



Wheel and workpiece rotating (
v
c

and
v
w
)



Wheel infeed at Rapid speed to start position (
dia
)



Wheel infeed by Coarse increments to Fine Feed start position (
dia
)



Wheel infeed at Fine feed to Final Size position (
dia
)



Sparkout

passes of wheel with no infeed


A
Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System


Automatic Plunge Cycle

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Cycle parameters

PlungeCoarseInfeed

As Double

PlungeFineInfeed

As Double

PlungeFineDia

As Double

PlungeStartDia

As Double

PlungeSizeDia

As Double

PlungeDwell

As Double

Motion parameters

dblXMovespeed

As Double


dblXRapid

As Double


dblXCoarseFeed

As Double

dblXFineFeed

As Double

dblXInfeed

As Double

dblXInfeedRate

As Double

intXDwell

as Integer


dblXStartPosition

As Double

dblXFinePosition

As Double

dblXSizePosition

As Double


dblZReversePositionL

As Double

dblZReversePositionR

As Double

dblZStartPosition

As Double


intFROSetting

As Integer

blnFeedHold

As Boolean

Cycle State Machine

Auxiliary variables

WheelSpeed

As Double

WorkSpeed

As Double

WheelheadOn

As Boolean

WorkheadOn

As Boolean

CoolantOn

As Boolean

Interfacing of Peripherals 1

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

RS232:

Com 1,

9600 Baud,

No Parity

Connect to 1300X Operator Panel

via RS232:


Read Data String
:

FRO value, button values, checksum


Write Data String:

Axis position displays,
Workspeed

display, LED values, checksum

Interfacing of Peripherals 2

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

RS232:

Com 2,

38400
Baud,

No Parity

Connect to Balance Systems VM9 TD

via RS232:


Read Data String
:

Signal values, Parameter values, checksum


Write Data String:

Operating commands, Parameter settings, checksum


OOD

(
O
bject
O
riented
D
esign) models software as people
would describe the objects in the world.


OOD

takes advantage of
class relationships

where objects of a certain
class (e.g. a class of
Vehicle
) have the
same characteristics
.
(e.g. a
Car
, a
Truck
, a
Bus
).


OOD

also takes advantage of
inheritance relationships

where a
new
class

of objects is
derived

by absorbing characteristics of an
existing
class

of objects and adding unique characteristics of its own.


An object of class
Convertible

has the characteristics of class
Car
, but
additionally, has a convertible roof.

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System


An Object has
attributes

. . .


i.e. size, shape, colour & weight.


. . . and exhibits
behaviours
.


i.e. a ball rolls, bounces, inflates & deflates.



A Class has
Properties

. . .


that describe its state and features


. . . and
Methods



that allow it to perform and experience actions

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

A fundamental object could be of type
Parameter
,

with various Attributes and Operations

(i.e. Properties and Methods)


Class:



Parameter


Derived classes:

CycleParameter








AxisParameter








VM9 Parameter








….

Properties:

Data Type


Methods:


ReadValue




Decimal places



WriteValue




Group




FormatValue




Level




ResetValue




Value




GetAddress




Min Value




….




Max Value




….

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Some System Parameters

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Axis Configuration

XAxisChannel


As
AxisParameter

XAxisPitch



As
AxisParameter

XAxisCount



As
AxisParameter

XAxisKV



As
AxisParameter

XAxisMaxSpeed


As
AxisParameter

XAxisMaxVolt


As
AxisParameter

Traverse Cycle

XCoarseInc



As
CycleParameter

XFineInc



As
CycleParameter

TraverseZFeed


As
CycleParameter

TraverseStartDia


As
CycleParameter

TraverseFineDia


As
CycleParameter

TraverseSizeDia


As
CycleParameter

Z0Dwell


As
CycleParameter

ZRevDwell



As
CycleParameter

TraversePasses


As
CycleParameter

VM20 Balancer Function

MinimumTolerance


As
BalanceParameter

MaximumTolerance



As
BalanceParameter

MaximumUnbalance



As
BalanceParameter

NominalSpeed



As
BalanceParameter

UnbalanceMeasuringUnit

As
BalanceParameter

BalancingCycleTimeout


As
BalanceParameter

CollectorType


As
BalanceParameter

BalancingHeadType


As
BalanceParameter

OptionRPMOutput



As
BalanceParameter

RS232 Configuration

Port


As RS232Parameter

Baudrate



As RS232Parameter

ParityChecking

As RS232Parameter

Handshaking


As RS232Parameter

InBufferSize


As RS232Parameter

OutBufferSize


As RS232Parameter

. . .
?

U
niversal
M
odelling
L
anguage


The UML
Class

diagram allows us to
m
odel

the
classes

in the system
and their
relationships
.

Class

diagrams :


model a
class as

a
rectangle
.


The
top

zone displays the
class name
.


The
middle

zone contains the
class attributes
.


The
bottom

zone contains the
class operations
.

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Progress

So far.....


Reactivation of machine tool

Electrical modifications, new workhead drive


Initial software with old hardware

Development software with new hardware


Axis configuration and movement

Familiarity with motion control package


Implementation of simple cycles


Design and build of control unit, IO conversion


Developed basic interface design


Communication with external equipment


Next steps....


Formal definition of software structure


Integration of
Touchscreen

Connection with VM20 unit (RS232/Profibus)


Axis movement via MPGs: Improved driver


A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System

Issues....


Machine removed for workshop

rebuild since

August 2011


New workshop with machines available

during

April 2012 ?????


VM9 Touch Detector unit with Hydrophone ?



And finally...

Any Questions ???

A Low
-
Cost, Expandable Open
-
Architecture Grinding Machine Control System


Thank you for your attention.....