On the morning of March 21, a white Austin police bomb squad truck pulled out of an obscure city facility near Austin-Bergstrom International Airport and rolled north, toward Pflugerville.
The truck had been used a handful times in the previous weeks as a serial package bomber spread fear through Central Texas, with five bombs that killed two people while injuring others, and a sixth bomb that was intercepted by officials.
Inside the truck was one of the bomb squad's most high-tech weapons: a squat, steel robot. Its mission: to search the Pflugerville home of the bomber, 23-year-old Mark Anthony Conditt, who hours earlier had blown himself up in Round Rock as law enforcement officials closed in on him. After Conditt's death, the robot was used to explore his house to make sure it was safe for investigators to enter.
"I don't know that we could have gained entry into (Conditt's) home safely without putting the robot in there first," said Austin police Lt. Courtney Renfro of the bomb squad. "I would be hesitant to send my officers into one of these situations without the robot. I probably wouldn't have in this situation."
As of last week, Austin police had received about 2,500 calls concerning suspicious packages since the bombings began March 2, Renfro said. The bomb squad was dispatched on more than 300 of those calls—and on seven of those calls, the robots were deployed.
Even with that small number of deployments, the robots were a crucial resource during the bombings, Austin police officials say. The robots are only used when officers believe the highest risk exists, such as when searching Conditt's home for explosives, said Jeff Joseph, one of the police bomb technicians.
The Austin police bomb squad has four robots, though only its two newer models were used during the recent bombings.
The robots are Andros HD-2 models from the Remotec division of tech company Northrop Grumman. They are roughly 4 feet long, 2 feet wide and 2 feet tall. Moving around on four tracked wheels, they can travel about 3.5 miles per hour. The robots are equipped with an extension arm that has a clamp for grabbing and searching items, a rotating surveillance camera and front and rear articulators, or short legs, that allow it to climb stairs. The HD-2 models are lighter—260 pounds—than their older counterparts.
The bomb squad received its first robot, which was a fraction of the size of its current models, about two decades ago. The squad is in the process of acquiring two new robots from Remotec. The new devices are Andros FX models, which cost roughly $300,000 each. One of those new models is expected to be delivered this week, Joseph said. The Andros FX has a number of upgrades, including eight tracked wheels that allow it to be more agile, along with a more versatile arm and camera.
More than robots
Founded in the 1970s, the Austin police bomb squad consists of seven bomb technicians. The squad has three options when responding to a call about a suspicious item, Joseph said. The team can investigate using one of its technicians, who wear formidable protective gear suit when handling suspicious items, it can deploy a rope device or it can dispatch a robot, Joseph said.
"For every incident we respond to, the first question we roll out is, 'Do we need to do it remotely?'" Joseph said. "It could just be because we did the last two or three incidents a different way, I want to change my response time, or just in case somebody were monitoring how we are doing it. And it helps eliminate some complacency."
But the robots aren't the department's only important technology. As calls of suspicious packages flooded in, many of the items were examined using mobile X-ray devices from tech firm Nex-Ray. The devices include a roughly foot-long X-ray machine that takes an image of whatever is inside a package and mirrors it on a tablet.
"These were invaluable," Renfro said. "They were used in just about every single one of the (suspicious package) calls. They saved hours and hours of these (officers) going out to calls where they would have waited for a response from one of these big trucks."
'A larger question'
While law enforcement officials point to the benefits of using robots in a variety of scenarios, some in the community have questioned how the devices are used, said Luis Sentis, a University of Texas robotics professor who has worked as a NASA contractor.
One of the main worries, Sentis said, is that advances in automation will one day make the robots police use too powerful. A highly publicized example of this concern came after Dallas police in July 2016 used a robot to deliver and detonate a bomb next to a shooter who had killed five police officers. While a grand jury ultimately ruled that the decision was justified, it raised questions about police use of technology.
"This is part of a larger question about should we eventually let robots (operate) without the supervision of a person," Sentis said. "We are engineers. We develop the technology with the hope that behavioral scientists, policymakers, etc. - they are going to create tunnels and decisions that will drive the engineering community the right way. Communities decide what is ethical or not. Regulators decide that."
Police robots shouldn't ever be used without a human controlling their moves, Joseph said. But he disputed the notion that the devices are too powerful.
"Our robots are pretty much remote-control cars. They don't do anything automatically," Joseph said. "I would have been really unhappy to approach one of those packages myself without a remote capability.
"Every single time we roll that thing out of the door, we're thankful we have it."
Even with Conditt dead, the threat of bombs is not over.
Last Thursday, more than a week after the serial bombings came to an end, three additional suspicious packages were reported to police.
The bomb squad was on guard again, with the robots ready to roll if needed.
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