Inspection By Robot

The Solo robotic inspection system from RedZone Robotics helps communities achieve substantial increases in productivity in the field phase of studies

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Contractors and municipalities are constantly alert for ways to make the process of inspecting underground pipes less time- and labor-intensive, especially in the field.


That explains the interest in side-scanning devices that quickly record panoramic images of the entire pipe circumference for later review in an office setting. That technology greatly reduces data-gathering time in the field.


The Solo robotic pipe inspection system from RedZone Robotics Inc. has a similar benefit. The system includes a fully autonomous robotic crawler, camera platform, image capture, and data-storage device. Available only as a leased unit, it eliminates capital investment in inspection equipment and the need for highly trained field inspection technicians and dedicated, specialized support vehicles.


Because the lease includes data archiving, interpretation, comprehensive condition reports and access to interactive online asset management tools, owners of even small infrastructure networks can get the benefit of top-of-the-line inspection and analysis technology.


The Solo system enables a single, modestly trained field technician to investigate and document multiple runs of 8- to 12-inch pipe simultaneously. The only limit to the number of simultaneous investigations is the number of camera units on hand and the technician’s agility at sequential deployments and retrievals. The manufacturer says a technician typically can keep four units busy.


RedZone Robotics personnel demonstrated the technology in the City of Pittsburgh, Pa. On hand were project manager Chris Atwood, marketing director Phil Johns, Solo technician Doug Soxman, reporting technician Jennifer Costello, and lead reporting technician Martin Breit.



The Solo unit, with or without attached cameras, appears symmetrical. Prominent on both ends of the cameras are LED light arrays that encircle the lenses, which in turn are protected by a transparent, field-replaceable plastic bubble. Cameras have a 360-degree field of view.


On close observation, the aft end is distinguishable by a back plate, from which emerges a small-diameter, Kevlar-like cord with its end tied in a loop. The cord is part of the control mechanism. Other points of asymmetry are the green start button, a data port, and the product nameplate, all on only one side. Data capture is totally ­symmetrical: As the device moves forward, it captures images from fore- and aft-facing cameras.


The most noticeable and colorful components are the pair of 2-inch-wide orange treads that resemble those of a military tank. One component of conventional inspection camera-crawler platforms is missing: There is no control or umbilical cable. From the moment the operator deploys the crawler and starts a traverse until he retrieves it, there is no direct human interaction. Deployment requires three other devices:

• A traditional telescoping deployment pole with hook, used to place the crawler into the flow channel in the manhole.

• A telescoping, compression-secured hanger bar installed at the top of the insertion manhole (the short cord is clipped to this bar).

• An armored laptop computer with WiFi communications capabilities that transmits location and pipe information to the crawler and is used to send it on its way.


Protected in the pressurized crawler body are rechargeable batteries, an onboard computer, and sensors that keep the crawler centered in the pipe’s channel and let it discern when it emerges from the pipe at the next manhole. Hidden in the back of the body, a reel maintains slight tension on the cord as part of the condition-sensing system.


At the end of a day’s field deployment, at a jobsite trailer, workshop or the user’s office, battery chargers and a redundant mass data-storage unit known as the Vault support the robot’s work. The Vault automatically downloads the day’s collected data and image files from up to eight robots using Ethernet cable connections.


A palm-sized hard drive is used to transport the data from the Vault to the RedZone Robotics offices in Pittsburgh. Data is sent by UPS or similar service on a weekly basis. Resident in RedZone headquarters are an array of data-storage devices and a computer system that enables highly trained reporting technicians to perform condition assessments and manage users’ information.


The system provides 16 GB of onboard data-storage capacity, enough for about 10,000 linear feet of inspections. Battery life in the crawler is adequate for two typical 400- to 500-foot traverses. Traverse speed is up to 30 feet per minute.



The equipment package demon-strated included four Solo robots, vault, extra batteries, a battery charging system and all related hardware. It also included the armored laptop, data analysis and reporting, and limited use of ICOM3 survey software.


The first part of the demonstration took place next to the RedZone office in the Lawrenceville neighborhood of Pittsburgh, in an 8-inch sewer pipe owned by Pittsburgh Sewer and Water. Soxman and Johns demonstrated the system in the field.


In the office, Costello and Breit demonstrated image interpretation and report preparation using NASSCO PACP standards. Atwood was present throughout, detailing the continuity that bridges individual tasks.


For the field demonstration, traffic cones were positioned around the SUV deployment vehicle parked beside the entry manhole. (In routine use, because the manhole would be open for only a short time, state Department of Transportation Work Zone Traffic Control regulations would not require “work zone” signage.)


With cones in place and the manhole cover removed, Soxman positioned the telescoping hanger bar at the top of the manhole, just below the lid-supporting lip, so that the lid could be replaced without disturbing the hanger bar. The tension-secured bar is a firm reference point (benchmark), from which the Solo unit measures its surroundings and interprets its situation.


Before insertion of the crawler, the end of the cord is slipped through a lightweight anti-chafing guide (tiger tail). The end is then secured to the hanger bar using an aluminum snap clip. The crawler is then lowered using the hook.


After a lights check to verify that the unit was properly responding to inputs from the laptop, Soxman sent it on its way. Additional robots could be deployed in each of any other pipes that enter or leave the same manhole. After all units are deployed, the manhole cover is replaced, and the operator moves on to the next manhole.


When it began to emerge from the pipe and enter the next manhole, the robot sensed the absence of a confining pipe, continued for a few feet, and stopped. This allowed the cameras to capture images of the manhole chimney.


After validating the sensor information three times, the device returned to the insertion manhole. This same sensing capability prevents it from falling into the abyss of a wet well. The robot would also return to the insertion manhole if it had met an obstacle that prevented forward movement.


When the crawler returned to the insertion manhole, the treads disengaged, and using the cord, it hoisted itself to a point just below the hanger bar, where it waited for retrieval, which required the same limited traffic safety as for insertion.


Before and after each traverse, to assure that all of the systems were performing as intended, the technician used the laptop and reviewed the camera views and captured images. After retrieval, the robot was cleaned using a garden-type sprayer supplied with the package. RedZone also specifies a degreaser. This addresses health and sanitation issues — important because the field technician typically replaces the rechargable batteries after two traverses.


The RedZone headquarters in Pittsburgh is both a data-interpretation facility and an engineering lab. When the portable storage device arrived at the office, it was taken to the main data download and storage facility, where redundant copies were archived.


Once stored, a report technician reviewed the collected images, adding condition notes using NASSCO’s Pipeline Assessment and Certification program (PACP) standards. Although the report writer perceived a movie-like display as the robot moved through the pipe, the images were actually a series of still photos stitched together by an automated movie-making software tool. The images enabled the technician to view panned, tilted and zoomed views through a full 360-degree field of view.


The report writer inserted electronic bookmarks into the data stream whenever he noted a defect, lateral connection or other feature. These allow future viewers to move from issue to issue without fast-forwarding. Each bookmark contains condition data saved to a database file.

Databases from multiple traverses are aggregated, enabling systemwide insights and planning. The file can be searched for defects of a specific type. This feature also enables tabular data presentation. In a similar manner, a start-to-finish, issue-by-issue report can be generated.


After the report was completed, a technician ran it through a quality assurance-quality control process. The electronic database and visual data file of each pipe segment were then burned to a DVD. Large data files may be saved to a small transportable hard drive. The storage device and hard-copy reports then can be mailed to the client.


With the data in hand, clients can use RedZone’s ICOM3 online asset management software. Infrastructure owners can plan maintenance and management programs, estimate materials needs, create project budgets, set work priorities, and do for themselves tasks usually reserved for engineers. Draft plans can be reviewed and verified by the owner’s in-house engineer or sent to a consultant.


Observer comments

Deployment vehicles can be parked near, but need not be directly next to, the insertion manhole. On busy streets, the absence of a parked vehicle at the manhole could reduce operator safety, but this could be overcome with a safety flagger.


As long as the technician can carry the 22-pound Solo unit to the manhole, the pipes entering the manhole can be inspected. Considering the nature of the work environment, cleanup and disinfection for worker safety are essential. This becomes a greater concern when a client uses a personal SUV or van as the deployment vehicle.


Manufacturer comments

“We have never had to dig up a Solo,” says Johns. Atwood adds, “There is no feeling like dropping four robots, eating lunch and retrieving complete inspection data on 1,200 feet of pipe.”


The unit is pressurized to prevent liquid intrusion. Its external components are resistant to high- and low-pH environments. “On average, clients are inspecting 3,000 to 5,000 linear feet of sewer per day,” says Atwood. “Operators experienced in traditional CCTV inspection can increase their productivity 300 to 400 percent.”


Johns observes, “The lease package provides everything an infrastructure owner needs except a deployment vehicle and traffic safety cones.”


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