APM Automation Solutions Ltd. Technology Overview Physics And Mathematics Avishai Bartov, VP R&D.

APM Automation Solutions Ltd.

Technology Overview

Physics And Mathematics

Avishai Bartov, VP R&D

Agenda

Introduction video – 3DLevelScanner Acoustic mapping technology

Inherent tradeoffs in Acoustics Level measurement – Narrow beam solutions Surface mapping with a wide angle beam

Gathering multiple echoes from the surface Calculate distance and direction of arrival 3D Surface reconstruction

Advance Radar Signal Processing Multi beams, multi frequency, Challenges Volume accuracy Self Cleaning Product Line Technology summary R&D Roadmap

May 2011 APM Annual International Partners Conference 2

Inherent Tradeoffs in Acoustics

Beam angle vs. Frequency θ - Beam opening angle λ - Wavelength D - Antenna size

D

D

Low frequency => Wide BeamMay 2011 APM Annual International Partners Conference 3

Beam Angle vs. Frequency

F = 2.5KHzλ = 13cm θ = 108⁰

D = 7.5cm



F = 4.5KHzλ = 7.5cm θ = 60⁰

D = 7.5cm



F = 10KHzλ = 3.4cm θ = 27⁰

D = 7.5cm



F = 20KHzλ = 1.7cm θ = 13⁰

D = 7.5cm

Narrow beam requires Ultrasonic Frequency


Inherent Tradeoffs in Acoustics

Sound is a pressure wave Dust particles and humidity in the air attenuate

the wave energy Attenuation grows sharply over 5KHz

Animation courtesy of Dr. Dan Russell, Kettering University

Low freq. => Effective dust penetrationMay 2011 APM Annual International Partners Conference 8

Signal Attenuation due to Dust/Moisture concentration in air

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Very high attenuation at ultrasonic frequencies

Acoustic Wave Attenuation


Signal Attenuation due to Dust/Moisture concentration in air

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Effective penetration at lower frequencies

Acoustic Wave Attenuation


Level Measurement With Narrow Beam

Goal: Measure the distance to a single, well defined point on the top surface Point measurement requires narrow beam Narrow =>Ultrasonic => poor dust

penetration

Distance measurement Traveling twice the distance C~340 Meter per Second Measuring the time of flight


Surface Mapping - Wide Angle Beam

Goal: Multipoint (X,Y,Z) measurement of the surface Large coverage => Transmit a wide angle pulse Wide beam=>Low freq.=> Effective dust penetration

Multiple reflected echo coming from Large surfaces and Extremum points Material / Silo Wall interface Silo Walls – False echo to be filtered

Separated by Time of Arrival


Direction Of Arrival (DOA) - Array Processing

• Example: 1D Array processing• Plan wave from angle - θ• Speed of sound - C• Array spacing - d• Time Of Arrival (TOA) is different

– Wave Path difference between Mic’s is

ΔP=d*Cos θ– Therefore, time of arrival difference:

ΔT =ΔP/C= d*Cosθ/C

Path difference => TOA difference => θ May 2011 APM Annual International Partners Conference 13

Multiple Antennas Enables Mapping

R3,θ3

R1,θ1

R2,θ2

R2R1 R3

Single antenna device

Multiple antennas device

Distance and direction

Distance measurement


3 Dimensional Surface Reconstruction

2 Dimensional Array of 3 Antenna Distance (R) Azimuth (Ф) and elevation (Θ) angles Convert R, Ф, Θ to Silo X,Y,Z coordinates

Optimal 3D surface reconstruction Extremum and boundary points Assume maximal material slope

Surface integral is VolumeMay 2011 APM Annual International Partners Conference 15

Advance Radar Signal Processing Range resolution: Key figure - The minimal distance

between two echo sources that are still separable

Signal to Noise Ratio (SNR): Required for the detection of small echo.

Long pulse => higher energy => better SNR It is a challenge to create pulses that excel in both range

resolution and SNR. A very active research topic for military radars


Advance Radar Signal Processing (2)

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Long pulse (7M ) - modulated sine wave, rectangular envelope

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After match filter -Very poor range resolution - limited to 7M!



State of the art - Chen and Cantrell 2002

After match filter - 50cm resolution, 1/13 side lobes

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APM Propriety – Patent pending

After detection: Significantly improved resolution, virtually no side lobes!

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3 targets: The importance of resolution and low side lobs

More points => Better mapping

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State of the art APM



APM proprietary scheme combines The resolution in detection of a short pulse The energy of a long pulse Using relatively small bandwidth, optimized for the

application Virtually no side lobes Applicable for the entire scanning range

Maintain constant resolution across the scanning range The longer the distance – the higher the pulse energy

Very efficient numerical implementation


Beam Steering Technology Beam direction can be tilted by modifying the signal phase in

the antennas

Significantly improve false echo separation and the investigation of complex surfaces by Looking at the same point through several beam tilts to

solve symmetry problems (i.e. dual echo at +10 and -10 degrees)

Pointing null to suspicious point to verify null reception Allowing high SNR at much larger sphere


Multi Frequency Technology Gather information from different perspectives Beam angle - Interaction with silos wall Interaction with material, specular vs. scattering reflections

• Different multipath trajectories• Different dust penetration capabilities • Improved robustness to acoustic noise sources


Directional False Echo Filtering

• Automatic mapping of false echo from silo structure• Multipath between the walls and ceiling of the silo

and the topography of the material• Filtering analysis based on

– Distance and Direction measurement– Information from other frequencies – Information from other beams– Silo geometry


Self Cleaning

Self Cleaning due to acoustic energy vibration


Volume Accuracy• Accuracy is < 3%• Accuracy estimation considerations

– Surface topography scenarios - typically, a complex surface yields more points!

– Direction of arrival accuracy

– Distance measurement accuracy

– Silo geometry

– Beams coverage – MVL for very large silos


Product Line

• 3DLevelScanner M/MV– 3DLevelScanner M

• Wide beam, Mapping capabilities• Min, Max and average level values

– 3DLevelScanner MV• Surface mapping visualization

• 3DLevelScanner MVL Series– For large silos and open bins– An integrated solutions of multiple scanner and a dedicated controller

• 3DMultiVision Software– Multi-site inventory monitoring system

• 3DLinkPro– Remote communication solution


Device types M/MV

3DLevelScanner M

• 70º opening beam angle - covers wide surface area• Real-time, accurate volume measurement• Suitable for big silos that require high accuracy and

inventory control• Provides minimum/maximum and average distance• Provides average volume at 4..20 mA output.• 3D Mapping – detects mapping points of the surface

area• Visualization of 3D mapping - disabled


Device types M/MV

3DLevelScanner MV

• 70º opening beam angle - covers wide surface area• Real-time, accurate volume measurement• Suitable for big silos that require high accuracy and

inventory control• Provides minimum/maximum and average distance• Provides average volume at 4..20 mA output• 3D Mapping – detects mapping points of the surface

area• Visualization of 3D mapping is enabled


3DLevelScanner MVL Series• Multiple scanners

– Large Silos, Warehouses, and Open bins– Number of scanners is application

dependant

• Integrated solution – Scanners synchronization– Merges reading into a unified surface– Min, Max and average level values– Visualization of the Measured Surface – Client server architecture


3D MultiVision software • Inventory monitoring S/W

– Real time tracking of multiple silos

– Monitoring bulk solid inventories in the entire site

– Multiple sites via remote connection

• Client / Server architecture• Server / scanners RS485 or

TCP/IP to M/MV/MVL Products• Multiple remote clients

connection • Provides

• Min / Max levels Volume and Mass

• 3D Visualization


Technology Summary• Low operating frequencies provides both effective penetration and

wide angle coverage

• 3D surface mapping based on digital array processing – Measure angle and distance to multiple echoes from the surface– Surface integral is volume

• Key technologies (Patent pending)– Advance RADAR signal processing

• Excellent Range resolution compared to known state of the art technology

• High energy via long pulses for long range measurements

– Multi beam technology – phase array based beam tilting– Multi frequency – Directional False echo filtering

• Self Cleaning due to acoustic energy vibration

• Volume accuracy is better than 3%

• Multi Scanner product addresses a new market of very large silos, warehouses and open bins


R&D Roadmap


R&D Roadmap main drivers - Accuracy (1)

• Superior accuracy is APM’s key value proposition• The new MVL product is targeting the lucrative high

end market of huge inventory silos, domes and open beans

• In the inventory market, measurement accuracy is translated to return on investment

• There is a growing demand for differential measurement that requires more than the current 3% spec

• Special bins and domes, never served before, are challenging


R&D Roadmap main drivers: (2)

Ease of use for traditional industry personnel

• APM’s products, especially supporting the high end MVL product is a challenge

• Today, most high end applications must go through customer support for approval, many of them must be approved by R&D.

• This is very inefficient cycle that delay the closing of lucrative sales.

• There is an urgent need for an expert system to support– Analyse the expected measurement accuracy– Recommend the required number of scanners– Determine the optimal installation positions taking into

account the application constrains– Recommend the optimal parameters configuration– Assist with connectivity to enterprise management S/W


R&D Roadmap main drivers: (3)

Applications for new markets

• Example – foam over liquid thickness measurement– Important problem in several industries such as Beer, Mining

and Oil.– Thick layer of foam on top of the liquid. – The challenge is to measure both liquid level and the level of

the foam above. – This new application represents for APM a huge potential

market that could not be served in the past


Wideband And Multiband Signals Based DOA Algorithm

• Goals– Significantly improve angular resolution – the ability to

separate two echoes of the same range– Achieve (~x2) range resolution improvement– Resolve the fundamental problem of spatial aliasing, when

wavelength is significantly smaller than the distance between the antennas

– Improve gain for single path reflections

2/mind

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Multi Antenna Array Architecture(1)

• The current 3 antennas architecture is the minimal required for locating the DOA of a reflected echo in 3 dimensions.

• A new design of between 7 to 10 elements will provide the following benefit:– An order of magnitude improvement in angular resolution

– Significant improvement of beam steering directivity

– Improved SNR

• The R&D effort will include:– Brand new algorithm, able to take advantage of the multi-element array

and provide a very significant improvement of angular resolution.

– Mechanical redesign of the antenna case

– Electronic board modifications to support a large transducers array


Multi Antenna Array Architecture(2)


Virtual Sparse Antenna Array By Synchronized Scanners In Real-time

• Real-Time synchronization of several scanners – H/W synchronization: echo in response to a pulse from one of the

scanners will be received by others.

– Located at some optimal positions

– Create a virtual (sparse) antenna

• Advantages– SNR improvement, significantly higher probability to receive a

specular (mirror) echo

– Significantly improved direction estimation

– Improved SNR (Linear)

• Main tasks– Project continuation from last year

– Waiting for the final Electronic board


Protective Cover Against Very Sticky Materials (1)

• APM scanners self clean due to the vibration of the relatively low frequency acoustic signal.

• It is a competitive advantage of APM, especially in the market segment of the more sticky materials

• The thin Radum is always clean for all materials.• Some very sticky materials accumulate inside the

horn, eventually blocking the acoustic signal• Currently there is no solution in the market for this

problem• Radars will be fully covered within few days• APM is in the best position to solve this customer

problem.May 2011 APM Annual International Partners Conference 41

Protective Cover Against Very Sticky Materials (2)

• The goal is to develop an add-on cover, to be installed at the very end of the horns

• The protective cover will be made of a Radum that will stay clean due to the acoustic vibrations

• The design should be done in a way that will not damage the acoustic path


Backup


Remote Communication3DLinkPro

The 3DLinkPro is used for remote assistance and tracking the measurements.

SIM card with SMS (Text) and GPRS enabled is required.

Automatic power reset when losing cellular signal.

Enable upgrading the 3DLevelScanner remotely to the various product types (M/MV).

Enable performing firmware updates remotely.


APM Automation Solutions Ltd. Technology Overview Physics And Mathematics Avishai Bartov, VP R&D.

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