Apparatus and method for dimensional weighing utilizing a laser scanner or sensor

The invention is a method and apparatus for measuring the dimensions of a parcel. The method comprises a series of steps utilizing the apparatus for determining each of the relevant dimensions of the parcel. The steps begin with the placing of a parcel on a flat surface in a field of measurement; the flat surface can be the weighing surface of a scale for calculating the parcel weight. A laser scanner is positioned and then rotated within its position so as to locate the lead and trail edges of the parcel, the left and right sides, and the top and bottom edges. The positioning data is then transmitted to a data processor which calculates the length, width, and height of the parcel. A conveyor belt for transporting the parcel to the measurement field can be utilized. A laser beam is transmitted toward a mirror so that the parcel must pass the mirror while the parcel is on the conveyor belt. The mirror is further positioned so that the laser beam is deflected toward an encoder bar located on the surface of the conveyor belt. During the transmission of the laser beam, a count is established which corresponds to a predetermined measurement scale. The count is continued until the transmission of the laser beam to the encoder bar is broken by passage of the parcel across the laser beam; the count continues when the beam is no longer blocked. The length and height of the parcel can then be determined.

RELATED APPLICATIONS 
Reference is made to application Ser. No. 08/775,672 (Attorney Docket No. 
E-377), entitled METHOD FOR DIMENSIONAL WEIGHING UTILIZING POINT 
DETERMINATION, assigned to the assignee of this application and filed on 
even date herewith. 
Reference is made to application Ser. No. 08/775,673 (Attorney Docket No. 
E-378), entitled METHOD FOR DIMENSIONAL WEIGHING UTILIZING SED LINE 
PROJECTION, assigned to the assignee of this application and filed on even 
date herewith. 
Reference is made to application Ser. No. 08/775,671 (Attorney Docket No. 
E-379), entitled METHOD FOR DIMENSIONAL WEIGHING WITH OPTICS, assigned to 
the assignee of this application and filed on even date herewith. 
Reference is made to application Ser. No. 08/775,549 (Attorney Docket No. 
E-383), entitled LOW COST DIMENSIONAL DETERMINING SYSTEM, assigned to the 
assignee of this application and filed on even date herewith. 
Reference is made to application Ser. No. 08/775,851 (Attorney Docket No. 
E-384), entitled COARSE VOLUME MEASUREMENT WITH INTERLOCK, assigned to the 
assignee of this application and filed on even date herewith. 
Reference is made to application Ser. No. 08/775,675 (Attorney Docket No. 
E-385), entitled AUTOMATIC DIMENSIONAL WEIGHING, assigned to the assignee 
of this application and filed on even date herewith. 
Reference is made to application Ser. No. 08/775,550 (Attorney Docket No. 
E-386), entitled DIMENSIONAL WEIGHING UTILIZING A FOLLOWING ARM MECHANISM, 
assigned to the assignee of this application and filed on even date 
herewith. 
Reference is made to application Ser. No. 08/775,214 (Attorney Docket No. 
E-387), entitled DIMENSIONAL WEIGHING UTILIZING A LINEAR DISPLACEMENT 
TRANSDUCER, assigned to the assignee of this application and filed on even 
date herewith. 
Reference is made to application Ser. No. 08/775,213 (Attorney Docket No. 
E-422), entitled APATUS AND METHOD FOR DIMENSIONAL WEIGHING UTILIZING A 
ROTATING SENSOR, assigned to the assignee of this application and filed on 
even date herewith. 
Reference is made to application Ser. No. 08/775,674 (Attorney Docket No. 
E-430), entitled APATUS AND METHOD FOR DIMENSIONAL WEIGHING UTILIZING A 
MIRROR AND/OR PRISM, assigned to the assignee of this application and 
filed on even date herewith. 
BACKGROUND OF THE INVENTION 
The shipping of goods from point A to point B has been a continual 
challenge to commerce. In recent years, with the development of certain 
efficiencies of transport and materials handling, carriers have been able 
to offer shippers mixed modes of transport, overnight delivery, better 
tracking of parcel movement, and discount rates in return for the 
utilization of labor and cost saving measures such as: bar coding; bulk 
delivery; and pre-sorting. 
One of the efficiencies of operation is the use of dimensional 
determination. Carriers have a need to accurately determine the amount of 
capacity required to meet shipping demands. By determining dimensions 
other than, or in addition to, weight, then shippers can pack goods more 
efficiently (i.e., build a pallet according to the needs of the transport 
mode) and carriers can fill a shipping container (ship, rail, truck, air) 
more efficiently. 
Carrier rates based on dimensional determination generally reward shippers 
for labeling parcels with dimensional characteristics or for separating 
out those parcels not meeting certain dimensional prerequisites. The 
technology associated with dimensional determination has proliferated as 
the requirements have grown. However, the essential movement of packages 
at a shipper site have remained the same; packages must still move through 
a prep area where identification labels of varied type are applied to the 
parcel, and where manifests can be assembled even if they are downloaded 
elsewhere. Package movement through the prep area is facilitated by 
chutes, conveyors, rollers, or simply through human intervention with the 
occasional platform for weighing, measuring, or marking. 
Dimensional determination is employed in various manners. U.S. Pat. No. 
5,004,929 for an OPTICAL SYSTEM FOR DETECTING THREE-DIMENSIONAL SHAPE; 
issued Apr. 2, 1991 to Kakinoki et al. (Kakinoki) is an example of 
dimensional determination designed to fit a specific need. In the case of 
Kakinoki, for instance, laser optics is employed to detect and measure a 
three dimensional shape. Kakinoki is important in its use of light power 
to compare images of items so that quality production can be maintained 
over a series of measured objects. If the images match, then the quality 
is maintained. Dimensional determination for shipping, however, is based 
on comparison of each object to be measured with a pre-existing but 
separate measuring standard. Kakinoki, on the other hand, compares each 
object being detected with other objects of its type, to determine a 
deviation. 
U.S. Pat. No. 5,331,118 for a KAGE DIMENSIONAL VOLUME AND WEIGHT 
DETERMINATION SYSTEM FOR CONVEYORS, was issued Jul. 19, 1994 to Soren 
Jensen (Jensen). Jensen discloses a system for determining the dimensions 
of a parcel moving on a conveyor belt. The parcel passes over a strip with 
indicia indicating units of incremental measure to determine a width, and 
alongside a similar strip to determine height. The length of the parcel is 
determined by interrupting the path of a photo-electric eye. Weight is 
determined by using a weigh-in-motion conveyor scale. The Jensen 
disclosure provides a good example of how parcel handling is enhanced 
through the use of simple techniques that do not require a profusion of 
new hardware or cause parcel movement to be inefficient. 
There is a need however, to reduce the great profusion of reader arrays by 
utilizing a single beam source for detecting measurement points; and, if a 
conveyor belt is being utilized, a system that provides a qualifying 
measurement to determine whether package movement along the production 
line can be pre-empted to remove or re-direct non-qualifying parcels would 
create an efficiency without driving up cost. 
The ability to continuously monitor a field to be measured is known in the 
art; consider U.S. Pat. No. 5,325,178 for a METHOD OF MEASURING THE 
DIMENSIONS OF MOVING OBJECTS, issued on Jun. 28, 1994 to Louis et al. 
(Louis). Louis teaches that the length, width, and height of objects on a 
conveyor belt can be determined by utilizing fixed position CCD cameras to 
measure along predefined axes. The disadvantage to Louis is that the 
measuring devices (i.e., the CCD cameras) are siting along fixed lines, 
and therefore, objects of varied dimension can not be accurately measured. 
Thus, an object of the present invention is to provide a cost effective 
means for determining the dimensions of a parcel. The ability of the 
shipper to enjoy reductions in rates from carriers by implementing certain 
efficiencies in operation, and to do so without slowing work flow or 
driving up costs, is a distinct advantage to be gained by the system user. 
SUMMARY OF THE INVENTION 
According to the invention, the object is achieved and the disadvantages of 
the prior art are overcome by a method and apparatus for measuring the 
dimensions of a parcel. The invention method comprises a series of steps 
for determining each of the relevant dimensions of the parcel. 
The steps begin with the placing of a parcel on a flat surface in a field 
of measurement; the flat surface upon which the parcel is placed can be 
the weighing surface of a scale capable of calculating the weight of the 
parcel. A laser scanner is positioned either above or below the surface 
position of the parcel and is further positioned behind the parcel. 
The laser scanner is rotated within its position so as to locate the lead 
and trail edges of the parcel; the positioning data is then transmitted to 
a data processor which calculates the length of the parcel by calculating 
the distance from the lead edge to the trail edge. The laser scanner is 
then rotated within its position so as to locate the left side and then 
the right side of the parcel. The positioning data for the left and right 
sides is transmitted to the data processor for calculating the width of 
the parcel. Finally, the laser scanner is rotated within its position so 
as to locate the top edge and the bottom edge of the parcel; transmitting 
the position points to the data processor and them calculating the height 
of the parcel by calculating the distance from the parcel top edge to the 
parcel bottom edge. 
As is apparent to those skilled in the art, the sequence of determining the 
length, width, and height of the parcel can be varied depending upon the 
needs of the system or its users. 
The calculated length, width and height of the parcel can then be displayed 
on a monitor and/or transmitted to a parcel processing system. 
Additionally, if the flat surface of the measuring field upon which the 
parcel was placed is the weighing surface or platter of a weighing scale, 
then the calculated weight can be displayed on the monitor as well and/or 
transmitted to a parcel processing system. 
The method utilizes a minimum of required hardware while leaving open the 
possibilities for optional hardware and processing capability. The 
apparatus for measuring the dimensions of the parcel include means for 
supporting the parcel for measurement; this supporting means can be any 
flat surface capable of meeting the rigors of parcel handling. A preferred 
embodiment of the invention, however, utilizes the weighing surface or 
platter of a weighing scale as the flat surface. The use of a scale allows 
the system to calculate the weight of the placed parcel. 
The apparatus further includes a laser scanner means for rotatably scanning 
a predetermined field for measurement data wherein the measurement data is 
representative of the parcel's length, width, and/or height. A calculator 
means is provided for calculating the parcel's length, width, and/or 
height from the measurement data. And, additionally, a data processing 
means is provided. The data processing means: controls the rotating 
movement of the laser scanner; receives and processes the measurement data 
from the laser scanner; transmits the measurement data to the calculator 
means for determining the actual measurements of the parcel based upon a 
pre-selected measurement scale; receives the calculated measurements from 
the calculator means; and then transmits the calculated measurements to a 
monitor and/or or to a parcel processing system. The monitor will display 
the calculated dimensions of the parcel for the use of the system 
operator, while the use of a parcel processing system allows the parcel 
dimensions to be further utilized for shipping and carrier processing. 
In an alternative embodiment of the present invention, a conveyor belt for 
transporting a parcel to the measurement field can be utilized. The parcel 
can be pre-qualified as a candidate for dimensional weighing by 
determining the parcel's length and height while being transported by the 
conveyor belt. 
To accomplish the limited measurement of a parcel while in transit, the 
parcel is placed onto a conveyor belt; to be transported into the field of 
measurement. A laser beam is transmitted from a transmitter located 
directly above and along the axis of the conveyor belt movement toward a 
mirror where the height of the parcel is predetermined. The mirror is 
located along the axis of the conveyor belt so that the parcel must pass 
the mirror while the parcel is on the conveyor belt. The mirror is further 
positioned at approximately a 45.degree. angle relative to the laser beam 
so that the laser beam is deflected downward at an angle of approximately 
45 onto the axis of the conveyor belt and toward an encoder bar located on 
the surface of the conveyor belt. 
The laser beam is returned from the encoder bar to the mirror and then to a 
receiver co-located with the laser beam transmitter. During the 
transmission of the laser beam, a count is established which corresponds 
to a predetermined measurement scale. The count is continued until the 
transmission of the laser beam to the encoder bar is broken by passage of 
the parcel across the laser beam as the parcel passes the mirror. The 
count is restarted when the parcel has passed the mirror and transmission 
of the laser beam is no longer broken. 
The length and height of the parcel are determined by calculating the 
period of time that the laser beam transmission was broken relative to the 
count while the laser beam transmission was not broken and then 
calculating an angle between laser bean and parcel at which the break 
occurred. The calculated length and height can then be displayed on a 
monitor and/or transmitted to a parcel processing system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Turning to FIG. 1, there is shown parcel P.sub.1 placed within a measuring 
field. System 10 comprises the measuring field. 
System 10 includes platform 12 which can be a simple rectangular platform, 
or can be of any shape that will effectively accommodate a parcel or 
package (hereinafter collectively referred to as "parcels") to be 
measured. In a preferred embodiment of the invention, platform 12 is a 
weighing scale capable of weighing the parcels placed upon the weighing 
scale. The weight of the parcel is calculated and the data transmitted 
from the weighing scale, via interface cable 18b, to central processing 
unit or data processing device 16 (hereinafter "CPU 16"). 
The surface of platform 12 is marked in such a way that the parcel will be 
placed thereupon in the best location for being scanned for its 
dimensions. The markings form a right angle on the surface of the platform 
such that the 0, 0 (x and y axis respectively) coordinate point is 
directly opposite the closest corner of the platform that is bisected by 
the neutral position of the beam being emitted by laser scanner 14. The 
placing of the corner of the parcel in the 0, 0 position will form three 
baselines 20, 22, and 24. 
The beam being emitted by laser scanner 14 bisects the closest corner of 
platform 12 while laser scanner 14 is in its neutral position. The 
movement of laser scanner 14 from its neutral position through one cycle 
of motion is continuous and at a constant rate. A full cycle of movement 
comprises three subcycles D.sub.1, D.sub.2, and D.sub.3. 
D.sub.1 comprises a movement from the neutral position to the right through 
an angle of 45.degree. while maintaining a position parallel to the 
surface below laser scanner 14, and thus along baseline 20; and 
additionally, a movement directly back to the neutral position along 
baseline 20. D.sub.2 comprises a movement from the neutral position to the 
left through an angle of 45.degree. while maintaining a position parallel 
to the surface below laser scanner 14, and thus along baseline 24; a 
movement directly back to the neutral position along baseline 24. D.sub.3 
comprises a movement from the neutral position up vertically through an 
angle of 90.degree. and thus along baseline 22; then, a movement directly 
back to the neutral position along baseline 22. Laser scanner 14 is under 
the control of CPU 16 and the data that moves therebetween does so along 
interface cable 18a. 
Laser scanner 14 emits a beam that has been calibrated so that laser 
scanner 14 will always return to the neutral position. The neutral 
position is known by CPU 16 such that an application program within CPU 16 
will use the neutral position to begin to determine the linear dimensions 
of a parcel such as P.sub.1. As laser scanner 14 begins movement D.sub.1, 
it emits a beam that is directed along baseline 20 at the known starting 
point. Laser scanner 14 essentially simultaneously emits a beam of steady 
pulse as it receives reflections back from its path along baseline 20. The 
reflections back from baseline 20 are measured in terms of the signal 
strength, and relative angle of projection, in order to determine the 
length of the parcel that is along baseline 20. When the measurement of 
the signal strength no longer matches the expected signal strength, then 
the end of the parcel has been obtained and the linear measurement of the 
parcel lying along baseline 20 can be determined. 
As laser scanner 14 begins movement D.sub.2, it emits a beam that is 
directed along baseline 24 beginning at the known starting point 0,0. 
Laser scanner 14 essentially simultaneously emits a beam of steady pulse 
as it receives reflections back from its path along baseline 24. The 
reflections back from baseline 24 are measured in terms of the signal 
strength, and relative angle of projection, in order to determine the 
length of the parcel that is along baseline 24. When the measurement of 
the signal strength no longer matches the expected signal strength, then 
the end of the parcel has been obtained and the linear measurement of the 
parcel lying along baseline 24 can be determined. 
As laser scanner 14 begins movement D.sub.3, it emits a beam that is 
directed along baseline 22 beginning at the known starting point 0,0. 
Laser scanner 14 essentially simultaneously emits a beam of steady pulse 
as it receives reflections back from its path along baseline 22. The 
reflections back from baseline 22 are measured in terms of the signal 
strength, and relative angle of projection, in order to determine the 
length of the parcel that is along baseline 22. When the measurement of 
the signal strength no longer matches the expected signal strength, then 
the end of the parcel has been obtained and the linear measurement of the 
parcel lying along baseline 22 can be determined. 
Turning to FIG. 2, there is shown an alternative embodiment of the present 
invention wherein representative parcel P.sub.2 is fed into the measuring 
field. System 30 comprises the measuring field. 
System 30 includes intake belts 32 being driven by rollers 34 such that a 
parcel as represented by parcel P.sub.2 is fed onto platform 36 which can 
be a simple rectangular platform, or can be of any shape that will 
effectively accommodate a parcel or package (hereinafter collectively 
referred to as "parcels") to be measured. The driving force of rollers 34 
can be provided by motor means (not shown) or by the force of belts 32 
being driven by motor means further up the conveyor (not shown). The 
driving action of conveyors is well known and need not be discussed herein 
for an understanding of the present invention. 
In a preferred embodiment of the invention, platform 36 is a roller-top 
weighing scale capable of weighing the parcels being passed over a 
plurality of rollers 37 of the weighing scale. The weight of the parcel is 
calculated and the data transmitted from the weighing scale, via interface 
cable 56e, to central processing unit or data processing device 54 
(hereinafter "CPU 54"). 
Parcel P.sub.2 is fed from the surface of platform 36 by the movement of 
rollers 37 to outbound belts 40 driven by rollers 38. There is a gap 
between belts 40; the purpose of which is to allow laser scanner 42 to be 
placed in the feed path of parcel P.sub.2. Slightly below laser scanner 
42, and also in the feed path, is polygonal mirror 44 driven by motor 
means 46 under control of CPU 54 via interface cable 56b. 
Laser scanner 42 and polygonal mirror 44 are located such that the beam 
being emitted by laser scanner 42 and reflected off of polygonal mirror 44 
bisects the closest edge of platform 36 when laser scanner 42 is in its 
neutral position. The movement of laser scanner 42 from its neutral 
position through one cycle of motion is continuous and at a constant rate. 
A full cycle of movement comprises D.sub.4. 
D.sub.4 comprises a movement from the neutral position up vertically 
through an angle of 90.degree.; then, a movement directly back to the 
neutral position. The signal from laser scanner 42 is reflected back from 
reflective apparatus 58 that forms a bridge over the feed path. Reflective 
apparatus 58 comprises two upright legs 59. Half the width of upright legs 
59 extend beyond platform 36, while the other half of the width of upright 
legs 59 is parallel to the sides of platform 36. Reflective apparatus 58 
can be made of a substantially rigid material and is coated on its inside 
surface with a reflective coating. The reflective coating can be applied 
in any one of a number of ways that are well known in the art and need not 
be discussed here for an understanding of the present invention. 
Laser scanner 42 is under the control of CPU 54 and the data that moves 
therebetween does so along interface cable 56a. Laser scanner 42 emits a 
beam that has been calibrated so that laser scanner 42 will always return 
to the neutral position. The neutral position is known by CPU 54 such that 
an application program within CPU 54 will use the neutral position to 
begin to determine the linear dimensions of a parcel such as P.sub.2. As 
laser scanner 42 begins movement D.sub.4, it emits a beam that is measured 
along a baseline beginning at the known starting point 0,0. Laser scanner 
42 essentially simultaneously emits a beam of steady pulse as it receives 
reflections back from reflective apparatus 58 and traces its path along 
the baseline. The reflections back to laser scanner 42 are measured in 
terms of the signal strength, and relative angle of projection, in order 
to determine the length of the parcel moving through the parcel feed path. 
As representative parcel P.sub.2 absorbs part of the beam of laser scanner 
42 when parcel P.sub.2 passes known starting point 0,0, the upward 
movement of the beam during D.sub.4 sends back a steady stream of 
reflected signals that are reduced in strength relative to signals that 
are reflected from reflective apparatus 58. When the measurement of the 
signal strength no longer matches the expected signal strength, then the 
end of the parcel has been reached and the linear measurement of the 
height of the parcel passing through the feed path can be obtained. When 
the signal strength returns to the expected level, then the linear 
measurement of the length of the parcel can be obtained by factoring the 
angle of the laser beam projection together with the length of time of the 
reduced reflection and the speed of the belts 32 and 40. 
The measurement of the width of the parcel passing through the feed path is 
obtained by measuring the signal strength transmitted by laser scanner 52 
which is located to one side of the feed path of the advancing parcel. The 
beam emitted by laser scanner 52 is reflected off of rotating polygonal 
mirror 48 located within the gap of the parcel feed path and between 
platform 36 and rotating polygonal mirror 44. Rotating polygonal mirror 48 
is driven by motor means 50 under control of CPU 54 via interface cable 
56d. 
Laser scanner 52 and polygonal mirror 48 are located such that the beam 
being emitted by laser scanner 52 and reflected off of polygonal mirror 48 
can move across the reflective apparatus 58 from the neutral 0, 0 position 
to the bottom of one upright leg 59 of reflective apparatus 58, back 
through the neutral position, to the bottom of the other upright leg 59 
and then back to the neutral position . The movement of laser scanner 52 
from its neutral position through one cycle of motion is continuous and at 
a constant rate. A full cycle of movement comprises D.sub.5. 
Laser scanner 52 is under the control of CPU 54 and the data that moves 
therebetween does so along interface cable 56c. Laser scanner 52 emits a 
beam that has been calibrated so that laser scanner 52 will always return 
to the neutral position. The neutral position is known by CPU 54 such that 
an application program within CPU 54 will use the neutral position to 
begin to determine the linear dimensions of a parcel such as P.sub.2. As 
laser scanner 52 begins movement D.sub.5, it emits a beam that is measured 
along a baseline bisected by the known starting point 0,0. Laser scanner 
52 essentially simultaneously emits a beam of steady pulse as it receives 
reflections back from reflective apparatus 58 and traces its path along 
the baseline, first to one side of the starting point 0, 0, then to the 
other side. The reflections back to laser scanner 52 are measured in terms 
of the signal strength, and relative angle of projection, in order to 
determine the width of the parcel moving through the parcel feed path. As 
representative parcel P.sub.2 absorbs part of the beam of laser scanner 52 
when parcel P.sub.2 passes known starting point 0,0, the upward movement 
of the beam during D.sub.5 sends back a steady stream of reflected signals 
that are reduced in strength relative to signals that are reflected from 
reflective apparatus 58. When the measurement of the signal strength no 
longer matches the expected signal strength, then the end of the parcel 
has been reached and the linear measurement of the width of the parcel 
passing through the feed path can be obtained. 
There is a lower cost embodiment of the invention contemplated in which 
scanner 52, rotating polygonal mirror 48, and motor means 50, together 
with their applicable data interface cables 56c and 56d are eliminated 
from the embodiment shown in FIG. 2. This embodiment would eliminate the 
width calculation of the parcel being measured, but would provide a 
threshold measurement for determining if certain parcels should not be 
processed for shipping under dimensional weighing guidelines. 
The processing steps of the embodiment described in FIG. 1 are shown in the 
flowchart of FIGS. 3A and 3B. 
Turning to FIG. 3A, the method begins at step 100 when the parcel to be 
measured is placed on top of a platform within the field of measurement. 
From step 100, the method advances essentially simultaneously to steps 102 
and 104. If the platform upon which the parcel has been placed is the 
surface of a weighing scale, then the weighing scale will determine the 
weight of the parcel at step 102 before advancing to step 116 where the 
weight data is stored in a memory of a data processing system. If the 
platform upon which the parcel has been placed is not the surface of a 
weighing scale, then the method will not perform step 102. 
As the parcel is being weighed at step 102, or if the platform is not the 
surface of a weighing scale, the method performs step 104 where a laser 
scanner located at one comer of the field of measurement establishes three 
baselines at a corner of the parcel to be measured where such corner is in 
contact with the surface of the platform. The corner from which the 
baselines diverge is designated position 0, 0 in a coordinate field and 
will be referred to hereinafter as the "neutral position." 
The laser scanner emits a beam that has been calibrated so that the laser 
scanner will always return to the neutral position upon completion of a 
measuring movement. The neutral position is known by the CPU that 
processes the data being received by the laser scanner such that an 
application program within the CPU will use the neutral position to begin 
to determine the linear dimensions of a parcel placed within the field of 
measurement. 
The beam being emitted by the laser scanner bisects the closest corner of 
the platform upon which the parcel has been placed while the laser scanner 
is in its neutral position. The movement of the laser scanner from its 
neutral position through one cycle of motion is continuous and at a 
constant rate. A full cycle of movement comprises three subcycles D.sub.1, 
D.sub.2, and D.sub.3. 
Step 104 corresponds to movement D.sub.1. D.sub.1 comprises a movement from 
the neutral position to the right through an angle of 45.degree. while 
maintaining a position parallel to the surface below the laser scanner, 
and thus along the baseline; and additionally, a movement directly back to 
the neutral position along the same baseline. 
From step 104, the method advances to step 106 where the length of the 
parcel is calculated. The calculation is derived from a measurement of the 
intensity of a beam emitted by the laser scanner. The neutral position is 
known by the CPU that processes the data being received by the laser 
scanner such that an application program within the CPU will use the 
neutral position to begin to determine the linear dimensions of a parcel 
placed within the field of measurement. The reflections back from the 
baseline are measured in terms of the signal strength, and relative angle 
of projection, in order to determine the linear dimension of the parcel 
that is along the baseline. When the measurement of the signal strength no 
longer matches the expected signal strength, then the end of the parcel 
has been reached and the linear measurement of the parcel lying along that 
baseline can be determined. 
From step 106 the method advances to step 108 where the laser scanner is 
rotated to measure along a baseline that is determinative of a linear 
measurement corresponding to the parcel's width. Step 108 corresponds to 
movement D.sub.2. D.sub.2 comprises a movement from the neutral position 
to the left through an angle of 45.degree. while maintaining a position 
parallel to the surface below the laser scanner, and thus along the 
baseline; and additionally, a movement directly back to the neutral 
position along the same baseline. Step 108 advances to step 110 where the 
linear dimension corresponding to the parcel width is calculated in the 
same manner as the parcel length was calculated. 
From step 110 the method advances to step 112 where the laser scanner is 
rotated to measure along a baseline that is determinative of a linear 
measurement corresponding to the parcel's height. Step 112 corresponds to 
movement D.sub.3. D.sub.3 comprises a movement from the neutral position 
up vertically through an angle of 90.degree. and thus along the baseline; 
then, a movement directly back to the neutral position along the same 
baseline. Step 112 advances to step 114 where the linear dimension 
corresponding to the parcel height is calculated in the same manner as the 
parcel's length and width were calculated. 
The method advances from step 114 to step 116 where the calculations 
derived from the measurement of the parcel's length, width, height, and 
weight are stored within a memory of the CPU for subsequent use in a 
parcel processing application program. From step 116, the method advances 
to step 118 where the stored data is distributed, under control of the 
CPU's application program, to those applications requiring the data as 
input. 
From step 118, the method advances along path A to re-enter the method flow 
at step 120 as shown in FIG. 3B. At step 120, the system displays the 
calculated dimensions and weight of the parcel to be processed. 
Essentially simultaneously to step 120, the calculations are input to a 
parcel processing program within the CPU at step 122 which applies the 
data against a look-up table of values that correspond to a shipping 
charge as determined by a carrier's dimensional weighing guidelines. From 
step 122, the method advances to a query at step 124 which asks whether or 
not the calculated dimensions of the parcel exceed a predetermined 
threshold value. The threshold value is determined by the carrier based 
upon a number of factors which include: class of service, mode of 
carriage; ease of handling; and, dimension. 
If the response to the query at step 124 is "YES," then the method advances 
to a query at step 128 which asks if there are special handling 
instructions associated with a parcel corresponding to the measurements of 
the subject parcel. If the response to the query is "NO," then the method 
advances to step 126. If the response to the query at step 128 is "YES," 
however, then the method advances directly to step 136 where the parcel is 
further handled according to pre-determined criteria which may include: 
rejection of the parcel by the carrier; alternate means of carriage; 
application of a different table of values for determining carriage 
charges; or, application of a service charge. 
Returning to step 124, if the response to the query at step 124 is "NO," 
however, then the method advances to step 126 where shipping charges are 
determined in respect of the parcel's dimensions and any other criteria 
established within the application program's data table values. From step 
126 the method advances to step 130 where the system prepares shipping 
documentation which might comprise: shipping labels; waybills; and 
appropriate barcoding. The method then prepares a carrier manifest, at 
step 132, indicative of parcels prepared for shipping. The method then 
advances to step 134 where the parcel is placed into its proper shipping 
channel. 
The processing steps of the embodiment described in FIG. 2 are shown in the 
flowchart of FIGS. 4A and 4B. 
Turning to FIG. 4A, the method begins at step 200 when the parcel to be 
measured is transported into the field of measurement by a conveyor or 
similar apparatus. From step 200, the method advances essentially 
simultaneously to steps 202 and 204. If the platform upon which the parcel 
has been placed is the surface of a weighing scale, then the weighing 
scale will determine the weight of the parcel at step 202 before advancing 
to step 216 where the weight data is stored in a memory of a data 
processing system. If the platform upon which the parcel has been placed 
is not the surface of a weighing scale, then the method will not perform 
step 202. 
As the parcel is being weighed at step 202, or if the platform is not the 
surface of a weighing scale, the method performs step 204. At step 204, 
the parcel is fed from the surface of the platform by the movement of 
rollers to outbound conveyor belts. There is a gap between the belts to 
allow a first laser scanner to be placed in the feed path of the parcel. 
Slightly below the first laser scanner, and also in the feed path, is a 
first polygonal mirror driven by motor means under the control of the CPU. 
The first laser scanner and the first polygonal mirror are located such 
that the beam being emitted by the first laser scanner is reflected off of 
the first polygonal mirror, bisecting the closest edge of the platform 
when the first laser scanner is in its neutral position. The movement of 
the first laser scanner from its neutral position through one cycle of 
motion is continuous and at a constant rate. A full cycle of movement 
comprises D.sub.4. 
Step 204 corresponds to movement D.sub.4. D.sub.4 comprises a movement from 
the neutral position up vertically through an angle of 90.degree.; then, a 
movement directly back to the neutral position. The signal from the first 
laser scanner is reflected back from a reflective apparatus that forms a 
bridge over the feed path. 
The first laser scanner is under the control of the CPU and the data that 
moves therebetween does so along an interface cable. The first laser 
scanner emits a beam that has been calibrated so that the first laser 
scanner will always return to the neutral position. 
When the linear dimension, corresponding to the height of the parcel has 
been scanned by the first laser scanner then the method advances from step 
204 to step 206. At step 206, the neutral position of the first laser 
scanner is known by the CPU such that an application program within the 
CPU will use the neutral position to begin to determine the linear 
dimensions of a parcel placed within the field of measurement. From step 
206, the method advances to step 208. 
At step 208, the parcel is fed from the surface of the platform, by the 
movement of rollers along its surface, to the outbound conveyor belts. 
There is a gap between the belts to allow a second laser scanner and a 
second polygonal mirror to be located such that the beam being emitted by 
the second laser scanner and reflected off of the second polygonal mirror 
can move across the reflective apparatus from a neutral position to the 
bottom of one upright leg of the reflective apparatus, back through the 
neutral position, to the bottom of the other upright leg and then back to 
the neutral position. The movement of the second laser scanner from its 
neutral position through one cycle of motion is continuous and at a 
constant rate. A full cycle of movement comprises D.sub.5. 
As the second laser scanner begins movement D.sub.5, it emits a beam that 
is measured along a baseline bisected by the point represented by the 
neutral position. The second laser scanner essentially simultaneously 
emits a beam of steady pulse as it receives reflections back from the 
reflective apparatus, under which the parcel is passing, and traces its 
path along the baseline, first to one side of the neutral position, then 
to the other side. The reflections back to the second laser scanner are 
measured in terms of the signal strength, and relative angle of 
projection, in order to determine the width of the parcel moving through 
the parcel feed path. As the parcel absorbs part of the beam of the second 
laser scanner when the parcel passes the neutral position, the upward 
movement of the beam during D.sub.5 sends back a steady stream of 
reflected signals that are reduced in strength relative to signals that 
are reflected from the reflective apparatus. When the measurement of the 
signal strength no longer matches the expected signal strength, then the 
end of the parcel has been reached and the linear measurement of the width 
of the parcel passing through the feed path can be obtained. 
From step 208, the method advances to step 210 where the measurement of the 
width of the parcel passing through the feed path is obtained by measuring 
the signal strength transmitted by the second laser scanner. 
The laser scanner emits a beam that has been calibrated so that the laser 
scanner will always return to the neutral position upon completion of a 
measuring movement. The neutral position is known by the CPU that 
processes the data being received by the laser scanner such that an 
application program within the CPU will use the neutral position to begin 
to determine the linear dimension corresponding to the width of the parcel 
placed within the field of measurement. 
From step 210 the method advances to step 212 where the parcel passes 
beyond the ability of the first laser scanner to project a beam upon the 
parcel. The method then advances to step 212 where the system calculates 
the length of the parcel. By calculating the known time that the parcel 
was within the emission/reception field of the first laser scanner, 
relative to the speed of the parcel's movement, the length of the parcel 
can be determined. The determination is well known in the art and need not 
be discussed herein for an understanding of the subject invention. 
The method advances from step 214 to step 216 where the calculations 
derived from the measurement of the parcel's length, width, height, and 
weight are stored within a memory of the CPU for subsequent use in a 
parcel processing application program. From step 216, the method advances 
to step 218 where the stored data is distributed, under control of the 
CPU's application program, to those applications requiring the data as 
input. 
From step 218, the method advances along path A to re-enter the method flow 
at step 220 as shown in FIG. 4B. At step 220, the system displays the 
calculated dimensions and weight of the parcel to be processed. 
Essentially simultaneously to step 220, the calculations are input to a 
parcel processing program within the CPU at step 222 which applies the 
data against a look-up table of values that correspond to a shipping 
charge as determined by a carrier's dimensional weighing guidelines. From 
step 222, the method advances to a query at step 224 which asks whether or 
not the calculated dimensions of the parcel exceed a predetermined 
threshold value. The threshold value is determined by the carrier based 
upon a number of factors which include: class of service, mode of 
carriage; ease of handling; and, dimension. 
If the response to the query at step 224 is "YES," then the method advances 
to a query at step 228 which asks if there are special handling 
instructions associated with a parcel corresponding to the measurements of 
the subject parcel. If the response to the query is "NO," then the method 
advances to step 226. If the response to the query at step 228 is "YES," 
however, then the method advances directly to step 236 where the parcel is 
further handled according to pre-determined criteria which may include: 
rejection of the parcel by the carrier; alternate means of carriage; 
application of a different table of values for determining carriage 
charges; or, application of a service charge. 
Returning to step 224, if the response to the query at step 224 is "NO," 
however, then the method advances to step 226 where shipping charges are 
determined in respect of the parcel's dimensions and any other criteria 
established within the application program's data table values. From step 
226 the method advances to step 230 where the system prepares shipping 
documentation which might comprise: shipping labels; waybills; and 
appropriate barcoding. The method then prepares a carrier manifest, at 
step 232, indicative of parcels prepared for shipping. The method then 
advances to step 234 where the parcel is placed into its proper shipping 
channel. 
As can be appreciated by those skilled in the art, a number of variations 
of the subject invention are possible. These variations include, but are 
not limited to: the ability of the system to select the order in which the 
baselines will be scanned to determine the linear measurements of the 
parcel; the use of a weighing scale as the platform within the field of 
measurement; the speed and characteristics of the conveyor apparatus 
utilized to transport parcels to and from the measurement field; and, the 
general abilities of the shipping system application utilized by the CPU. 
Additional variations that are contemplated, include, but are not limited 
to: the shape or configuration of the platform for supporting the parcel 
or package to be measured; the sequence of laser scanner moves that 
comprise a cycle; the means for supporting the laser scanners; whether or 
not the system is a standalone system or a node within a network; and, the 
number of surfaces which the rotating mirrors possess. 
It is to be understood that the present invention is not to be considered 
as limited to the specific embodiment described above and shown in the 
accompanying drawings, which merely illustrates the best mode presently 
contemplated for carrying out the invention and which is susceptible to 
such changes as may be obvious to one skilled in the art, but rather that 
the invention is intended to cover all such variations, modifications and 
equivalents thereof as may be deemed to be within the scope of the claims 
appended hereto.