This 400-pound, sidewalk-roaming security robot just got fired

A five-foot tall, 400-pound robot with four surveillance cameras just got fired from its security job. Right before Christmas.

The San Francisco animal welfare non-profit, SF SPCA, rented the 'bot to roam its parking lot and grounds, ostensibly in response to a recent burglary. But to the dismay of neighbors, the SPCA also let the robot patrol the public sidewalk outside the property.

Now, after being sent a deluge of threats, Ars Technica reports the SPCA has pulled the plug on its robot... for now.

The SPCA rented its robot from Knightscope, the security startup that made headlines earlier this year when one of its robots drowned itself in a pool at Washing D.C. mall. While private businesses are certainly free to deploy security robots on private property, these surveillance machines generally aren't allowed to patrol public spaces -- like the local sidewalks in San Francisco's Mission district.

The city had already warned the SPCA to keep its security robot off of neighborhood sidewalks.

According to a letter obtained by the San Francisco Business Times, last week the city's Department of Public Works (DFW) told the SF SPCA to keep its robot off of the sidewalks "without a proper approval."

Still, it seems the Knightscope robot could return to its wandering ways if the DFW grants the animal welfare organization a permit to monitor these public walkways. Mashable has contacted the DFW about what conditions a business -- or anyone, really -- would be allowed to deploy a security robot in a public space, and will update this story upon hearing back.

According to the San Francisco Business Times, the SPCA used the robot to deter a homeless encampment from setting up tents on the sidewalks adjacent to the building and parking lot, where discarded needles and bikes made it all the more difficult to walk. In response, apparently some members of the encampment covered the Knightscope robot in a tarp and lathered its sensors with barbecue sauce.

Knightscope offers four different security models that vary in their mobility, but each contains sound sensors and cameras. The SPCA specifically rented KnightScope's "K5" model, which is "best suited for securing large outdoor spaces," according to the KnightScope website. The K5 is just over five feet tall, weighs in at 400 pounds, and has four cameras.

These relatively new robots are still learning their way, so folks can certainly be wary of the slow-moving, though rather imposing robots. In 2016, a KnightScope K5 robot ran over and injured a toddler at a mall in California.