X-Serie S_705.pdf - 第48页

48 Vision sensor technology PCB position recognition Bad board recognition Ink spot criteria Methods • Synthetic fiducial recogn ition method • Mean gray scale value • Histogram method • Template matching Shapes and size…

Vision sensor technology

PCB position recognition

Description

The optimum fiducial shapes

vary according to the condi-

tion of the surface. When

using bare copper surfaces

with low oxidation, it is advis-

able to take the single cross,

as the high amount of infor-

mation provided helps

achieve the greatest

accuracy. Rectangle, square

and circle are less "informa-

tive" but save space and can

even be used when oxidation

is at an advanced stage. Cir-

cle or square are advisable

for tin-plated structures as

the ratio of the fiducial

dimensions to the presolder

thickness is particularly

favorable.

Fiducial criteria

Locate 2 fiducials

Locate 3 fiducials

X-/Y-position, rotation angle, mean PCB distortion

additional: shearing, distortion separately in X and Y direc-

tion

Fiducial shapes Synthetic fiducials: circle, cross, square, rectangle, dia-

mond, circular, square and rectangular contours, double

cross, pattern: any

Fiducial surface

Copper

Tin

Without oxidation and solder resist

Warpage of fiducial  1/10 of structure width, both with good

contrast to environment

Dimensions of patterns

min. size

max. size

0.5 mm

3 mm

Fiducial environment Clearance around reference fiducial not necessary if there

is no similar fiducial structure in the search area

Dimensions of synthetic fiducials

Min. X/Y size for circle and rectangle 0.25 mm

Min. X/Y size for annulus and rectangle 0.3 mm

Min. X/Y size for cross 0.3 mm

Min. X/Y size for double cross 0.5 mm

Min. X/Y size for diamond 0.35 mm

Min. frame width for annulus and rectangle 0.1 mm

Min. bar width / bar distance for cross, double-cross 0.1 mm

Max. X/Y size for all fiducial shapes 3 mm

Max. bar width for cross/double-cross 1.5 mm

Minimum tolerances generally 2% of nominal dimension

Max. tolerances generally 20% of nominal dimension

Vision sensor technology

PCB position recognition

Bad board recognition

Ink spot criteria

Methods • Synthetic fiducial recognition method

• Mean gray scale value

• Histogram method

• Template matching

Shapes and sizes of fiducials/structures for

synthetic fiducials

other methods

For dimensions of synthetic fiducials, see page

min. 0.3 mm

max. 5 mm

Masking material Good coverage

Recognition time Depends on the method: 20 ms - 200ms

Description

In the cluster technology

each subpanel is assigned

an inkspot. If this is present

during the measurement via

the PCB vision module, the

corresponding subpanel is

populated. This function

helps prevent unnecessary

costs caused by placement

of defective panels.

Technical data for PCB position detection

PCB fiducials

Local fiducials

Library of bad panel recognition

Up to 3 (subpanels and multiple panels)

Up to 6 for the long board option (optional PCB fiducials

are output by the optimization.)

Up to 2 per PCB (may be of different type)

Up to 255 fiducial types per subpanel

Image analysis Edge detection method (singular feature) based on gray

scale values

Illumination type Front lighting

Fiducial recognition time 0.1 s

Field of vision 5.78 mm x 5.78 mm

Virtual inkspot handler (option)

The virtual inkspot handler allows you to scan in inkspots from an external system. These ink-

spots can then be allocated to the relevant board.

03015/01005 Placement

In its standard version, the

SIPLACE X-Series is

designed for placement of

03015 (0.3 mm x 0.15 mm)

and 01005 components (0.4

mm x 0.2 mm).

The SIPLACE component

library already contains the

contours and dimensions of

03015 or 01005 compo-

nents. Specially developed

component nozzles of type

1005 are also available for

the SIPLACE X-Series.

These are adjusted to the

shape and size of the 03015

or 01005 components and

have - as with all other

SIPLACE nozzles - a highly

wear-proof ceramic tip and

flexible nozzle seat. This

guarantees maximum preci-

sion and process reliability.

Optimized pickup is guaran-

teed by the ideal feeding

conditions in the SIPLACE X

feeder module. The smaller

the elements to be picked up,

the more accurate the pickup

needs to be.

Pickup is performed contact-

free to compensate minor

inaccuracies e.g. from com-

ponent or pocket tolerances

and to prevent mechanical

damage to the components.

The design of the SIPLACE

X feeder modules takes this

problem into account: new

motors and the reduced use

of fine mechanics help. Small

components can be placed

without performance loss

with minimum pitch and irre-

spective of the larger compo-

nents which are next to the

03015 or 01005 component.

This equates to

true 03015 or 01005 capa-

bility. As a rule with 03015 or

01005 placement, a finely

tuned overall process is the

basic requirement if you want

to achieve excellent results.

All the process parameters

must be optimized. The

SIPLACE team will be

pleased to advise you on

how to do this.

03015/01005 measurement

results and ambient condi-

tions

As the dpm values and

pickup rates for 03015 or

01005 placement depend

greatly on the respective

measuring conditions, it is

not advisable to specify

these without considering the

corresponding ambient con-

ditions.

The following table shows typical values for 01005 placement,

which can be achieved with a SIPLACE X4i S, provided the

relevant underlying conditions are fulfilled:

Machine type SIPLACE X4i S

Placement head SpeedStar with component camera

type 23

MultiStar with component camera

type 30

Nozzle type 4008 (SpeedStar)

2005 (MultiStar)

Feeder module type 4mm SIPLACE X feeder module

8mm SIPLACE X feeder module

2x8mm SIPLACE X feeder module

Station software From 707.1

SIPLACE Pro From 11.2

Pickup rate 99,97%

Dpm rate 5

Pad width 200 µm

Pitch 100 µm

Components (L x W x H) 400 µm x 200 µm x 200 µm (±20 µm)

Number of pixels for a

01005 component

275

Solder paste type 5

Te m

late thickness 60