Scientists at the University of Washington claim to have built a robot that can perform utility check ups on miles long high voltage power cable much like human workers, with the added advantage that it can find faults in the cables before they really show up.
“This is the first robot built that can inspect power cables autonomously looking for incipient failures. It can find cables that may need repair, before they cause problems,” says assistant professor of electrical engineering Alexander Mamishev.
Internal damages in a cable don't show up through the insulation very often. As such, even power company engineers find it difficult to know the weak points in the electrical grid, with the result that they function even after suffering the long-term effects of hurricanes, landslides or wind storms, until one fine day, when they completely break down.
But, now all that is about to change. The prototype robot, developed by Mamishev and his team over the past five years has been successfully tested on underground power lines at New Orleans.
According to Mamishev, New Orleans was chosen for the field test because of the widespread damage to the city's power system. More than a year after Hurricane Katrina, conditions in New Orleans still remain unsafe, Mamishev adds.
According to him, the robot's unique ability lies in pinpointing problem spots by using information from the surface of the cable to assess the condition of what's inside. The robot can negotiate tight curves and ride along the insulated distribution cable scanning for internal damage.
It looks like an insect and uses three sensors, a heat sensor that detects heat dissipation; an acoustic sensor that listens for partial electrical discharge; and a sensor that detects ‘water trees’, filaments of water that have seeped into the insulation, the robot looks for faults.
"Engineers can monitor the robot via wireless connection and watch the robot's surroundings through a front-mounted video camera," Mamishev adds.
According to the research team, the robot is ideally suited for checking underground or buried cables, as sending a person to monitor miles of cable by hand is not only tedious and costly but also impractical.