Date post: | 13-Apr-2017 |
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Engineering |
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Dimensioning, Weighing & ScanningHOW TO SELECT DWS SYSTEM FOR YOU?
Vineet Govani | Project Analyst
2Main Components of a DWS
07-Feb-2017
Vineet Govani | Project Analyst
3Typical Uses of a DWS
Verification of customer-declared weight and size data Check data against profile in customer database Compliance with Weights and Measures regulations Track and trace of shipments Check for missing parts in a shipment
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Vineet Govani | Project Analyst
4What Does a DWS Provide
Identification (ID)
Capture item ID for correct sorting, tracking and allocation of weight & size data
Weight Verify weight data for invoicing and load planning
Dimensions Verify measurement data for invoicing and load planning
Dimensional Weight
Divide volume by a dimensional factor to determine an objects dimensional weight
Billable Weight
Compare dimensional weight with actual weight to determine the billable weight
ShapeRecord shape data to reject an item that is too large to be sorted or that require a surcharge because it is un-stackable.
Image Take a picture of items measured for proof of correct invoicing and package condition
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Vineet Govani | Project Analyst
5
Determining Which Solution to Use
THINGS TO CONSIDER
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Vineet Govani | Project Analyst
6Ask yourself the following questions
What type of objects are handled (parcels, pallets, etc.)? How many items are proccessed daily? How many items are procecessed during peak hours? What shape are the items that pass through the facility? What is the current level of automation? What is the speed of your sorting equipment? Where is there the possibility to further automate processes?
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Vineet Govani | Project Analyst
7Static DWS vs dynamic DWS
Static DWS
Dynamic DWS
Without Manual Intervention
Can be configured to stop if parcel missing vital info
Can send signal to sorter to divert package for manual check or re-sort
Require Manual Operation
Lower cost, simple processing
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Vineet Govani | Project Analyst
8Singulated flow and Mass flow
Singulated FlowRequires a certain
distance between objects
Suitable for Parcels
Mass flowObjects are not evenly
spaced
Objects often side by side or touching
Not possible to capture weight data
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Vineet Govani | Project Analyst
9Conveyable vs Non-conveyable Objects
Easily handled by one personConveyable• Easily placed on conveyor belt, table or into a vehicle • Usually solid in shape• Ride smoothly on a conveyor
Inconvenient for one person to handleNon-conveyable• Examples include heavy boxes, tires, chests, bicycles or cans
Placed on a pallet or a skidPalletized• Size, shape, weight or quantity make it impossible for• one person to handle
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Vineet Govani | Project Analyst
10Regular vs. Irregular Dimensioning
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Vineet Govani | Project Analyst
11Measuring Surface
A measuring solution should provide sufficient accuracy on all surfaces Some technologies struggle to provide accurate measurement of items
that are wrapped in shiny, reflective plastic, or that have a surface color that blends into the measuring background
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Vineet Govani | Project Analyst
12Throughput
Throughput and conveyor speed are usually inversely proportional to weighing accuracy.
Sometimes a compromise has to be made between accuracy and conveyor speed/throughput.
In order to maintain high weighing accuracy at high throughput, a solution is to divide the line over multiple scales or to implement a dual-scale solution. Dividing the line reduces the throughput over each weigh cell, while
maintaining constant throughput for the system.
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Vineet Govani | Project Analyst
13
Building a DWS Solution
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Vineet Govani | Project Analyst
14
Dimensioning OPTIONS TO CONSIDER
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Vineet Govani | Project Analyst
15Dimensioning Considerations
Shape of the goods Number of measurement points Use of technology : Shadowing or reflective
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Vineet Govani | Project Analyst
16Measurement Points
The more points a device generates, the more precisely it can determine the dimensions of an object
More Points
More Precisio
n
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Vineet Govani | Project Analyst
17Positioning of Measurement Points
Parallel light beams Parallel beams see a more
representative view of an object’s characteristics
Angled beams Angled beams can easily be
shadowed by the edges of an object and the beam may be blocked from seeing important details.
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Vineet Govani | Project Analyst
18Shadowing vs. Reflective Technology
Shadowing Technology The object interrupts a light path and
a shadow profile is observed by the device
This method works with all objects regardless of object surface
Reflective Technology Reflective devices use a type of
radiation that is reflected back from the object
There are materials and surfaces that absorb or reflect too much or too little radiation to allow good measurements
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Vineet Govani | Project Analyst
19Light Curtain Technology
Definition: A shadow parallel beam technology that uses hundreds of
measuring points on the top and the sides of an object. Advantage:
Very small precision ranges can be obtained with this technology.
Construction: Light curtains consist of arrays of infrared emitters and
receivers. Infrared transmitters are placed on one side and transmit
their radiation to the receiver on the other side. Working:
One transmitter and the corresponding receiver are active simultaneously.
As the object is moved through the device on conveyors, the silhouettes are stored in a computer.
07-Feb-2017
Vineet Govani | Project Analyst
20Parallel Infrared Laser Rangefinder (PILAR) Technology
Definition: PILAR is a reflective parallel-beam technology, using modulated infrared light that measures thousands of points
looking at the object from the top Benefit:
A very small precision range can be obtained with this technology. Working:
Laser range-finders measure time of flight of light. The range-finder light path is scanned across the package with a polygon and a mirror arrangement. The light path is precisely parallel down to the package enabling it to recognise all details of the item being
measured. A complete three-dimensional picture is formed.
Limitation: Because this technology is reflective, some objects will not be measured. The technology is capable of determining whether an object reflects enough light to give correct results.
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Vineet Govani | Project Analyst
21Recommendations
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Vineet Govani | Project Analyst
22
Weighing OPTIONS TO CONSIDER
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Vineet Govani | Project Analyst
23Considerations
Speed and throughput Weighing resolution Maximum weight
Accuracy Inversely depends on
Speed/throughput Accuracy increases as conveyor
speeds and line throughput decrease Proportionally to Stability of object
The more stable an item is during weighing, the higher the accuracy
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Vineet Govani | Project Analyst
24Weighing Technology
Strain-Gauge Load Cell Electromagnetic Force Restoration (EMFR)
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Vineet Govani | Project Analyst
25Weighing Technology
Strain-Gauge Load Cell Suitable for non-legal-for-trade
applications
Electromagnetic Force Restoration (EMFR) Suitable for legal-for-trade
applications where high accuracy is required at high speed
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Vineet Govani | Project Analyst
26Recommendations
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Vineet Govani | Project Analyst
27
Scanning OPTIONS TO CONSIDER
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Vineet Govani | Project Analyst
28Scanning Considerations
Required minimum barcode resolution Height and length ratio of barcodes Placement of barcodes on a parcel or pallet Level of automation and possibility for manual intervention
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Vineet Govani | Project Analyst
29Resolutions
Resolution: Minimum Width of line in barcode or minimum spacing 0.25mm 0.30 mm 0.38 mm
The wider the spacing and thickness of the lines, the higher the minimum resolution should be.
0.25 mmLow resolution
Ability to read less dense barcode
Smaller reading areaMore readers
required to cover more area
Otherwise Need to choose higher
resolution0.30 mm
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Vineet Govani | Project Analyst
30Laser Based Barcode Scanner
- Easy to set up, connect and aim - Read codes fast enough to accommodate high speeds- Achieve a large scanning area and working range.
Limitation of read rate. It requires..• Code quality ANSI grade B or higher• Made of paper and not displayed in a plastic case• Limited variation of the code skew and pitch angle (+/- 20°)• Clear of straps or other objects• Undamaged
07-Feb-2017
Vineet Govani | Project Analyst
31Image-Based Barcode Readers
- Higher read rate than laser scanners- Able to read codes degraded by damage, orientation or distortion- Analysis software reconstructs the data from any legible portion of the image
- Cost
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Vineet Govani | Project Analyst
322D Barcodes
Immerging Technology Ability to stop product counterfeiting More information coding ability Examples
QR Code Data Matrix PDF417
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Vineet Govani | Project Analyst
33Scanning Configuration
Overhead barcode reader Barcode reading tunnel
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Vineet Govani | Project Analyst
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Vineet Govani | Project Analyst
35
If you cannot measure it, you cannot manage it
- PETER DRUCKER
Vineet Govani | Project Analyst | /VineetGovani
07-Feb-2017