Technology Innovation
InfoSense’s solution suite is based on a common technology developed over the past five years. Our early investigations
into detecting blockages led to a two year feasibility study for using acoustics to detect blockages ensued. Extensive field
measurements were conducted with the assistance of partnering utility engineers. Based on this early work and through an
NSF SBIR grant to InfoSense, Dr. Howitt developed signal processing algorithms for assessing the condition of sewer line
segments based on acoustic measurements, and proved their effectiveness.
Our novel technology is based on measuring the signal received from an active acoustic transmission within a sewer line
segment. From the received signal an acoustic profile is obtained. The acoustic profile represents the sound energy a pipe
transmits in a given state of operation. Commonly encountered sanitary sewer defects, such as roots, grease and
breakages naturally absorb or reflect acoustic energy; this changes the pipeline’s acoustic properties and produces a
measurable impact on the acoustic profile. Our algorithm exploits these variations to provide a real time evaluation of the
pipeline segment’s blockage condition.
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Unique Technology
Current sewer inspection tools were not designed to determine where cleaning resources should be deployed and are not a
viable solution. The SL-RAT has been shown to be an effective cleaning diagnostic tool at 1/10th the cost of cleaning. This
finding is independently reported in Charlotte Mecklenburg Utilities 2011 Annual Report . The SL-RAT can revolutionize
cleaning operations, moving the industry to a more efficient proactive blockage maintenance program which reduces SSOs
without increasing cost.
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Key Features
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Easy to operate and to economically justify – CONTACT US for more detail
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Works in long pipe segments as well as smaller 6-8” diameter feeder lines
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No contact with waste flow
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No confined space entry required
No need to clean pipes prior to inspection
Products
Sewer Line Rapid Assessment Tool (SL-RAT™) InfoSense’s Revolutionary Acoustic Inspection Tool for
Wastewater Collection System Assessment
Sewer Line – Rapid Assessment Tool or SL-RAT TM
FOCUS CLEANING EFFORT – REDUCE CLEANING BY OVER 50%
PRE-MAINTENANCE INSPECTION – PERFORM LOW COST BASIN ASSESSMENTS
ELIMINATE REPEAT AND DOWNSTREAM OVERFLOWS
POST CLEANING – QUALITY ASSURANCE
THINK SL-RAT FOR RAPID BLOCKAGE ASSESSMENT
The SL-RAT is our highly portable onsite assessment tool that provides a sewer line blockage assessment in less than 3
minutes. The SL-RAT is composed of two components – the Transmitter (or TX unit) and the Receiver (or RX unit). Each
SL-RAT device is sold or leased as a uniquely configured “pair” – with the TX providing the active acoustic transmission
through the pipe (think of the TX as “yelling” down the pipe) and the RX providing the microphone and signal processing
capabilities to listen and interpret the received acoustic signal (think of the RX as the brain “listening” for the blockage and
processing the blockage assessment result). Additionally, each SL-RAT component is equipped with GPS and the ability to
communicate between the TX and RX via RF – thus providing your organization with world class data labeling, data
registration, and test validation capabilities.
Have additional questions concerning the SL-RAT Operations & Capabilities – take a look at the SL-RAT FAQ or CONTACT
US.
SL-RAT FAQ
InfoSense SL-RATTM Acoustic Pipe Inspector – FAQ’s
Q:
How does the SL-RAT acoustic inspection technology work?
A:
Our technology relies on the fact that sound traveling thru air mimics the flow of water thru a pipe. We use an
active transmitter – think of it as the part “yelling” down the pipe, coupled with a receiver – the “brain” that uses sophisticated
algorithms and a patented process to interpret blockages based on what it “hears” coming thru the pipe.
Q:
What are the benefits of this new technology over existing pipe inspection methods?
A:
Because the acoustic method takes advantage of the fact that air and water flow similarly thru a pipe, the SL-RAT
can provide a blockage assessment up to 10X faster than CCTV, for less than 1/10 th the cost per foot, and without the need
for pre-cleaning or contact with the waste flow. Need we say more?
Q:
How long does it take to do a measurement?
A:
An assessment of pipe blockage for a sewer line segment is typically attained in less than 5 minutes after the
manhole covers are popped. A typical two man crew can inspect 8-10,000 feet of pipe per day independently, and without
the need of a cleaning crew for support.
Q:
What kind of pipe does the SL-RAT work in, and does pipe geometry matter?
A:
The SL-RAT is typically tuned for use in 6”-12” diameter unpressurized collection pipe with a flow-level capacity at
measurement that is below 90% of capacity. The algorithms can be tuned to larger pipes if needed. Since the SL-RAT uses
sound energy to detect blockages, it can go around turns and flow over obstacles – unlike CCTV. The type of pipe does not
matter –although clay pipe with significant joint offsets will typically show as “dirtier” relative to other types of pipe such as
cast iron and PVC.
Q:
What is the maximum segment length the SL-RAT can reliably measure across?
A:
Depending on ambient noise levels, our customers have obtained measurements reliably from up to 800 foot
distances. We anticipate the device can go even further than that depending on the situation.
Q:
What is the cost to operate the device?
A:
We have found the device costs less than $0.10/foot for inspection – including a two man crew and a service
vehicle.
Q:
How could we incorporate the SL-RAT into our maintenance and cleaning program?
A:
Our customers typically use a dedicated 2 man SL-RAT crew to quickly assess a subdivision or basin for dirty
segments and blockages. The assessments can then be used to focus on the specific “problem” segments for further
detailed CCTV inspection, repair, or cleaning. We have found that the SL-RAT tool can reduce your miles cleaned by 4060% while not degrading SSO performance.
Q:
What are the output results and how are they stored?
A:
The results are available to the user at the time of testing. Additional data such as time stamp, user ID, and GPS
location are stored in an encrypted format on the device that can be uploaded for archiving and further analysis to our cloud
based Sewer Line Data Organizer via USB connection to a PC.
1.
Q:
If I wanted to acquire an SL-RAT, what are my options?
A:
We offer three programs –
A field trial which includes one month of device use and 4 days training and coaching from an experienced InfoSense
representative
2.
An operating lease for up to 3 years
3.
Outright purchase
All programs include a one year limited warranty and the option to subscribe to our SL-DOG data organizing software
package
Q:
Does the depth of the manhole affect the measurement?
A:
No. We have run tests to depths of 30 feet and found no appreciable loss in measurement quality
Q:
Can multiple SL-RAT receivers (RX devices) be connected to one SL-RAT transmitter (TX device)?
A:
Yes this is technically possible. In practice, most of our customers have found very few practical field situations
where it would make sense to use multiple receivers with one transmitter.
Q:
Can your device pinpoint where a blockage is and what it is?
A:
The SL-RAT is a rapid assessment tool that is designed to quickly identify “problem” segments. Once a blockage
is detected with the SL-RAT, a more detailed method such as CCTV can be focused to learn more details about the
problem.
Q:
What exactly does the device measure?
A:
It measures the dissipation of sound energy thru the airspace within the pipe between the sewage flow and the pipe
wall. The more aggregate obstructions within the pipe – such as roots, grease, debris, joint offsets, hammered lateral
connections, cross bores, etc – the more the sound energy is blocked. Our device measures this “energy gap” and then
develops a blockage assessment. The assessment uses a proprietary algorithm based on a statistical model of sound
behavior in conduit that was developed thru several years of empirical research on sewage lines.
Q:
Do we need to shutdown or reduce the flow thru a pipe prior to using the SL-RAT?
A:
There is no need to modify the flow when making measurements. In other words, the SL-RAT does not impact
normal collection system operations.
Q:
If it is measuring blockage in the “free space” above the flow of water in the pipe, how does the algorithm deal with
pipes that are at >75% of capacity?
A:
As the free space in the pipe becomes more constricted by the water flow so will the acoustic signal used to
measure the available excess capacity within the pipe. Simply put, as the water level increases above 75%, the blockage
assessment will tend to decrease until at full pipe the assessment is zero.
Q:
And, can it detect debris under the water flow?
A:
The blockage assessment is primarily based on the air gap above the flow. The assessment can be impacted by
debris under the flow, if the debris causes a “bump” in the flow or in the case of sediment if it causes a rippling effect in the
water.
Q:
How repeatable are the measurements?
A:
The blockage assessment resolution (0 to 10 scale) has been well matched to the measurement repeatability and
accuracy.
Q:
What is the likelihood of getting a false positive – i.e., what is the likelihood the device will say a pipe is clean when
it is in fact blocked?
A:
The measurement algorithm has been designed to be conservative, i.e., if it errors, it will declare a pipe to be more
obstructed than it actually is. This has been proven to be the case in current head to head comparison studies with CCTV
and the SL-RAT acoustic inspection. The beauty of the design is that obstruction that block water flow also block sound.
Sewer Line Data Organizer or SL-DOG TM
KNOWLEDGE = POWER
CONVERT ASSESSMENT DATA TO ACTIONABLE SAVINGS OPPORTUNITIES
BETTER SCHEDULE CLEANING ACTIVITIES
BETTER MANAGE INSPECTION ACTIVITIES
MAXIMIZE YOUR PIPE CLEANING EFFECTIVENESS
SL-DOG MAKES ADDED SENSE OF YOUR ACOUSTIC SENSOR DATA
Our Sewer Line Data Organizer, or SL-DOG™, software-as-a-service (SaaS) application uploads your SL-RAT blockage
assessment data to a secure online environment from any properly configured web-enabled computer. Once uploaded to
the SL-DOG, your field operations data is at your command for making intelligent choices such as:
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What pipe segments can be skipped in our cleaning schedule?
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What pipe segments need further investigation or remediation?
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Which individual segments are blocked or largely blocked?
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How are my inspection crews performing?
How does a “before” and “after” view look?
The data is available for online download – in customizable views – to a user-base that is defined by your organization’s
requirements. Your data can be output in a Windows compatible format or in a custom format that can be integrated with
your existing Quality Control, Asset Management, and GIS systems among others.
As part of your annual subscription to the SL-DOG environment, InfoSense can also provide updates to the SL-RAT device
– such as new blockage-detection algorithm advances as well as providing your organization with the latest acoustic
inspection support services that you demand to optimize cleaning crew performance.
Sound interesting?
Down load SL-DOG Spec Sheet – InfoSense SL-DOG System Specs and Requirements 3-29-13.pdf
See an example of the types of reports you can create in minutes with SL-DOG – GLENWATER BASIN REPORT (402 kB)
Would you like to customize or automate the export of data from SL-DOG to your applications – such as a GIS or EAM
application?
To inquire about our integration services – please Contact Us!