Robot’s camera is a diver’s friend

By Ty Lim

Before human divers enter Metro Vancouver’s City sewers to conduct repairs, their robotic ally, known as a camera crawler, must go down to inspect the damage.

A camera crawler is a robot equipped with a camera that human operators can control from the surface.

Bill Cameron owns Dougness Holdings inc., a company that inspects Metro Vancouver’s sewers using camera crawlers. 

Cameron’s semi-trailer vacuum truck will first flush the sewer with enough water to fill a small swimming pool at high pressure, then a cutter robot is lowered down by his crew and driven through the pipe to clear any roots that would block the crawler’s path.

Cameron said roots grow between openings in the sewer pipe’s joints when they are not installed properly.

Next, the crawler is lowered into the manhole by its tethered power source. A human operator like Brandon Maynard can then remotely drive the crawler through the sewer, using a screen and control panel linked to the crawler’s camera.

Sewer divers feel for defects in pipes

But the process is not as simple as it sounds.

Sometimes, when cold air on the surface flows down through the warm dank air in the sewers, the crawler’s camera can fog up.

“You can’t see a thing, it’s just all fogged up,” said Maynard.

Maynard said it would be easier if  he could inspect the sewer walls with his own eyes rather than the hazy camera lens.

While sewer divers can see and feel for defects in sewer pipes that a crawler’s camera might not easily spot, they are fortunate that some obstacles in the sewer are seen by the crawler first, and not the human diver.

To Cameron, the most surprising obstacle he encountered was a live Raccoon.

“He backed up and got out,” he said. “He just took off,” Cameron said.