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PMR crossing a police line

Updated: Apr 11, 2023

2022 09 14 Bern Grush

Here is a video from Twitter that illustrates several issues regarding the regulation of public mobile robots (PMRs). In this sequence, the PMR happens to be a delivery robot, but it could have been a parking enforcement or street-sweeping robot. The tweet’s description of the event (“forces its way”) appears to be inaccurate, as explained below. (and confirmed in an addendum.)

A food delivery robot forces it’s way across a police crime scene.

In sequence…

See the scooter at 0:10, representing potential navigation barriers. This sidewalk happens to be quite wide, but that cannot always be the case, especially in my city, Toronto, a city with many narrow or missing sidewalks. A robot cannot move or step over such an obstacle (at least not yet, but that is coming). In Toronto, when I come upon an obstacle, usually a garbage can, I can move it aside or walk around it into the street if I need to. This happens several times daily for me, an avid walker.

See that the robot crossed the intersection on red at 0:45. There may be mitigating circumstances (for example traffic control may have been set to 4-way red), but I have seen other amateur videos of PMRs in which such mitigating circumstances were not present. This is an important issue, and since robots (or their teleoperators) are often programmed (or instructed) to wait until a fresh green signal or a fresh walk signal is available, I note this as a potential error and a critical concern.

While I cannot criticize this particular circumstance with certainty, I can point out that the matter of crossing intersections is probably the most critical aspect of public mobile robot (PMR) safety and is critically important in draft technical standard ISO 4448-16. The draft states that such devices shall wait for a fresh walk cycle when the crosswalk is signalized.

The nature of the police event makes this a good illustration of aspects of draft ISO 4448-16 that deal with arrest and seizure. That sounds dramatic, and this incident appears mostly innocent and merely clumsy on the part of the teleoperator (note the device also crossed a police line — an additional 'fault' that we will now add to the draft standard). Even (or especially) if the device was in "level 4" mode (rather than teleoperator, “level 2” mode) at the time of filming, this is exactly the reason for the several sub-paragraphs of draft ISO 4448-16 that deal with arrest, seizure and impounding. The events that are in this video should not happen regardless of teleoperation level — unless under specific police direction which I can neither ascertain nor rule out from the footage.

Caution: We cannot know the full story of this incident from this film alone. Why? If the device was under teleoperator control at the time of filming, the teleoperator has a speaker and mic and may have been speaking with the person who lifted the police tape. In other words, it may be the case that the proximate humans in the situation intended (even invited) the PMR to pass, and the bystander who was filming this did not hear or record that. Furthermore, while I suspect this particular robot was delivering food or groceries, in the future such devices may be in the service of police (or another emergency team) and could be bringing supplies of some sort to the team. However, as we see the robot simply continuing on, that is not the case here. ISO draft 4448 already considers the use of PMRs in police service.

Still, the film is extraordinarily instructive and useful for defending the cause of both safety and orchestration standardization, and I thank FilmThePoliceLA for their unwitting help.

The event in this film should not be seen as an “edge-case,” even though in these early days one might see it that way. When PMRs are operating at scale, happening upon any police, fire or EMS circumstances would be a daily affair — thousands per day, eventually. Standard procedures (jurisdictionally nuanced) must be followed, independent of the levels of automation of the device in question.

As the reader may now infer, the necessity for the ability of police to insist on re-routing or seizure is important regardless of the circumstances underlying this particular event.

Although flagged once at 0:10, note two more scooters at 1:00; this time exactly at the intersection curb. It is an egregious insult to pedestrian safety that the city being filmed permits this.

Lastly, note the disturbing dialogue captured at 1:25. The standard deals with hazardous goods (including explosives) through registration, ID, orchestration, and container security. These aspects of the standard must be understood and enforced by each jurisdiction to manage this aspect of PMR use.

Note: the current draft of ISO 4448-16 is available under Members Resources.

Addendum 2022 09 17

This TechCrunch story (Kristen Korosec, 09 16) explains a bit more about the subject video.

According to the article, the PMR… “approached the intersection and a human operator took over, per the company’s internal operating policy. Initially, the human operator paused at the yellow caution tape. But when bystanders raised the tape and apparently ‘waved it through,’ the human operator decided to proceed…”

The CEO of the company operating the PMR continued: “The robot wouldn’t have ever crossed (on its own) … there’s a lot of systems to ensure it would never cross until a human gives that go ahead.”

As I suspected, a teleoperator was in control and was indeed flagged through. The teleop procedure may be questioned, but this was in no way misbehaviour on the part of the robot, which during the video sequence had the same agency as does a poodle on a leash. The decision to proceed was an agreement between the bystander(s) and the teleoperator.

The CEO is further quoted as saying: “[r]egardless of the reason, [this] should not have happened. [Our company] ... is working on a new set of protocols for the human and the AI to prevent this in the future...”

In my opinion, this is an easy fix. A teleoperator, in addition to peering through the robot’s sensory systems, simply needs to be trained to take a detour around any form of emergency (EMR, fire, police) or other high-alert circumstance regardless of any offer from a bystander. (Police direction could be an exception.) An extra couple of blocks should make little difference to the operating company compared to any unintended consequences while passing through an uncertain, unmapped situation.

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