First responders on the ground at the Miami Beach-area condo that partially collapsed last week have used several tech tools to aid the treacherous search-and-rescue effort.

Rescuers deployed sonar and camera equipment early on as officials scoured the rubble for survivors. Heavy machinery was brought in to remove some bits of the pancaked building materials. Yet, nearly 150 people remain unaccounted for. And officials still have a tedious mission ahead as teams try to avoid falling debris and other unforeseen obstacles.

Does that mean it is time to send in the robots? It depends. Scouting robots might not be as susceptible to smoke inhalation and can snake through tight corridors in deadly conditions. But they also pose technical challenges, and are not always as helpful as they are designed to be when navigating complex environments at a moment’s notice, experts say.

The Miami-Dade Fire Department has at least two robots in its arsenal that the Massachusetts-based robotics company Teledyne Flir overnighted to assist with the Surfside, Fla., rescue effort. The gadgets are designed to operate where it is nearly impossible for humans to go.

“They can also go where humans shouldn’t go,” said Tom Frost, Teledyne Flir’s vice president of unmanned ground systems. “In a collapse situation like this, the pile is structurally unsound and constantly vulnerable to shifting. It’s much safer to have a robot crawl deeper into a void than to have a person crawling into that void.”

It is unclear if first responders have used the devices, however.

Teledyne Flir’s machines have some features that could come in handy as rescuers search through a mound of collapsed concrete. One of its microrobots can be tossed onto unstable rubble and will then roll into crevices humans cannot see or fit into. The company also sent a 50-pound automated machine with an arm to pick up and move around objects.

Teledyne Flir was formed last month after Teledyne Technologies, a $15 billion aerospace electronics firm, bought out Flir, a 42-year-old software company, in an $8 billion deal. The combined companies develop tech meant for deep sea, space and military missions.

The firm’s devices sent for use in the condo incident are equipped with thermal sensors, cameras and two-way radios built to aid during high-stakes missions. The tech was deployed at the World Trade Center collapse in 2001 and has since been used by law enforcement agencies during barricade situations.

The throwable “FirstLook” robot weighs about five pounds, is about the size of a brick and is built to withstand 16-foot drops onto concrete. It looks like a tiny military tank, sits on track wheels and has two arms to climb small obstacles. The arms also enable it to turn itself upright when flipped over, according to the company.

“You can take this robot and throw through a window or throw it on a roof, and get to really hard to access places,” Frost said.

The larger robot, “PackBot,” is about the size of a suitcase. It is designed to roll over rubble, navigate narrow passages and tote loads under about 40-pounds. They are both built to run semi-autonomously, which means some features are automated, while others require a teleoperator.

Tossable robots are not exactly new. The scouting and surveillance tools have been used by law enforcement and military personnel for years. Still, there are limitations.

Radio signals might not be able to penetrate deeply into the rubble. There might not be any useful places on-site for the robots to go. And robots can get stuck, causing yet another problem.

That is what happened in 2010 when rescuers in New Zealand tried finding 29 miners trapped inside a coal mine. The nation’s defense force sent in a camera-equipped robot to search for signs of human life, and it ended up short-circuiting and holding back the mission.

“You don’t want a robot to fail in the one spot that would block any other robot or person from getting in,” said Robin Murphy, a professor of computer science and engineering at Texas A&M. She worked on robotics-related recovery missions during 9/11, Hurricane Harvey and various other disasters. “We’ve got to make sure the robots are actually helping.”