A number of four-legged robot dogs have been deployed in the workforce for applications like inspections, security and public safety among others. At their core, these four-legged robots are mobility platforms that can be equipped with different payloads depending on the type of information that companies want to gather. 

Competition in the four-legged robot market is heating up. In the U.S., Boston Dynamics has been developing its 70-pound Spot robot for about 10 years. Nearby, MIT has also been working on a smaller four-legged bot it calls "mini cheetah." Ghost Robotics in Philadelphia is making robots geared toward military applications, while abroad, Swiss-based Anybotics is making a four-legged robot it calls Anymal for industrial customers. And Chinese companies like Deep Robotics, Weilan and Unitree Robotics are all building their own versions, though these last two companies seem to be at least partially focusing on the personal robotics market.

According to Allied Market Research, the global inspection robots market generated $940 million in 2020 and is expected to reach close to $14 billion by 2030. Take for example National Grid, an electric and gas utility company that serves customers in Massachusetts, New York, and Rhode Island. The company has been using two robots made by Massachusetts-based Boston Dynamics to do routine inspections. The robots are equipped with LIDAR to help them navigate, as well visual and thermal cameras to take detailed photos and thermal images of the equipment in the substation. Prior to using Spot, most inspections at National Grid's substations were done by people. In some cases, operation of the substation would have to be temporarily shut down, because it would not have been safe for humans to do the inspections while the equipment was still on. 

"We consider the investment in the robot to be a prudent investment because it improves the safety operating conditions for our employees," says Dean Berlin, lead engineer of robotics technology at National Grid. "The robot also presents an advantage in that it's very repeatable. It collects the images from the same angle, from the same vantage every single time, which is very useful because it allows us to compare images collected at different times to each other to be able to see any trends or changes in behavior."

Others who've used Boston Dynamics' robot dog, Spot, include pharmaceutical group Merck and BP, which is using the robot to autonomously read gauges, monitor corrosion and measure methane on some of its oil rigs in the Gulf of Mexico. Malaysian oil and gas company, Petronas, is using robot dogs made by Anybotics to inspect its offshore platforms. Brazilian mining corporation, Vale, is another early adopter of Anybotics' Anymal. Having completed initial testing, Vale is now in the process of purchasing a robot to do inspections and gather data about the condition of equipment in one of its mines. Vale says having Anymal help with inspections saves its staff from having to go into potentially dangerous spaces, which are often filled with dust, noise and rotating equipment parts. BASF, a German-based chemical company is also testing Anymal at one of its chemical plants, where the robot is gathering visual, thermal and acoustic data of BASF equipment. Both Spot and Anymal have also been deployed on construction sites, and in the case of Anymal, at train yards to perform train inspections.

"These companies typically need to send out their teams of educated people to collect data about the state of their plant. And so their vision is with these types of robots, such as Anymal, to automate some of these tasks making sure that their people are safe and can save on some of the costs associated with actually transporting people on site," says Péter Fankhauser, CEO and co-founder of Anybotics.

Other use cases for quadruped robots are just starting to catch on. One of the most controversial has been using these robots for defense. In May of 2021, the New York City Police Department said that it would stop testing of one of Boston Dynamics' Spot robots earlier than planned because of fierce public backlash. 

"Spot's role in public safety is one of keeping people out of harm's way. The NYPD was trying to use Spot in exactly that fashion where Spot was going to be the point of communication to a potentially barricaded and armed suspect who had hostages. That's a good use case for a robot, " Boston Dynamics CEO Robert Playter told CNBC.

Though the robot in the NYPD incident was not armed and was being remotely controlled by a police officer, concerns over fully autonomous robots being weaponized has led to the formation of an initiative known as the "Campaign to Stop Killer Robots." The coalition aims to ban the development, production and use of fully autonomous weapons. Among its supporters are Tesla CEO Elon Musk, the late Stephen Hawking and hundreds of A.I. experts.

For Ghost Robotics, the defense market is the company's bread and butter. The Philadelphia-based company says that out of its 20 plus customers, 90% are U.S. and allied foreign governments. One of those customers is the U.S. Air Force, which is using Ghost Robotics' Vision 60 robot to do security patrols around several bases. The Air Force says the robots can operate in a wide range of temperatures and are equipped with 14 sensors to help provide situational awareness. Ghost Robotics has also inked a deal with Singapore's Defense Science and Technology Agency. The agency says it will test and develop use cases for four-legged robots for security, defense and humanitarian applications.

Other use cases for robotic dogs are just starting to catch on. So far, Spot has been deployed to check the vital signs of Covid-19 patients in hospitals, take radiation measurements at nuclear power plants like Chernobyl, and remind people to maintain social distance amid the pandemic. NASA has also been sending teams of Boston Dynamics' robotic dogs into caves to see if they can one day be used to search for life on other planets. Farmers Insurance also said that the company will deploy Spot alongside its claims personnel to assess damage caused by hurricanes, tornadoes and other climate events.

Experts predict the insurance industry alone will spend $1.7 billion on robotics systems in 2025. And other industries may follow suit. Amid the pandemic, a tight job market is forcing many companies to turn to automation. A survey done in December of 2020 by McKinsey, showed that 51 percent of respondents in North America and Europe said they had increased investment in new technologies during 2020, not including remote-work technologies.

"As a company, we're really pushing towards having this artificial workforce being adopted, where humans and robots work shoulder to shoulder to solve difficult problems," says Fankhauser. "And our vision is that people shouldn't do work which is dangerous in places they shouldn't really be. So our vision within the [next] 10 years that it becomes standard to hire either a person or a robot to do a certain job."

But they don't come cheap. Anybotics' Anymal costs $150,000, but the company says this includes the full autonomy platform, which comes with LIDAR and a docking station. Ghost Robotics' Vision 60 robot also costs around $150,000. Boston Dynamic's entry-level "explorer" Spot robot starts at $75,000, but does not include a self-charging dock and is more limited in its autonomous capabilities when compared to the company's more expensive "enterprise model." The payloads are also not included in the price tag. Take National Grid's robot for example. Although National Grid would not share with CNBC how much it paid for the robot, just the thermal cameras and LIDAR it uses alone cost upwards of $57,000. Boston Dynamics says that it has sold several hundred Spot robots so far, while Anybotics has sold fewer than 100 robots.

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