Patients and staff rarely see them.
Visitors to Forth Valley Royal Hospital - unless they happen to be HRH Prince Philip - will never come face to face with them.
However, if not for the dedicated team of 13 workers who cover vast distances in the tunnels below the hospital, patients would not get their meals delivered every day.
Like all of us, these workers need to take a break and recharge the old batteries at times - but in this case it does not mean a cup of tea and a hob nob.
These guys literally plug into a charging bay for an hour before setting off on their rounds.
Automated Guided Vehicles (AGV) may look like miniature forklifts, but they behave more like your average manual worker - as The Falkirk Herald discovered after spending an hour in their company.
After descending into the AGVs’ “lair” you are quickly greeted by the sight of the large rectangular objects, numbered one to 13, trundling to and fro like upright mobile fridge freezers.
You can hear them moving around the corridors, but the AGVs are mostly silent and never grumble as they get on with the daily grind.
Thankfully Gordon Reid, Forth Valley Royal IT manager, was on hand to speak up for these unassuming members of staff. He opened with what could be perceived as a chilling statement - especially by people familiar with ‘Terminator’-style science fiction predictions of robots enslaving humanity.
“The AGVs are not aware of us, unless we get in the range of their sensors. Then we become another object for them to avoid and then get on with their work.
“In the hospital there are only 120 staff members cleared to work in the tunnel system. Patients will never see an AGV - they travel and work in an environment removed from patients and visitors.
“There is also no manual requirement for outside control - the AGVs are programmed to do certain tasks and then carry them out. Prince Philip was here earlier in the year and he was quite impressed by them.
“The longest journey an AGV has to make takes 25 minutes. When the AGV reaches about 60 per cent power it heads for one of the charging bays spread throughout the tunnels.
“It can usually run for two hours before it needs to recharge.”
Gordon said there had been no accidents or incidents in the 13 months the AGVs have been working at the hospital. These robots - which travel at a walking pace of 1.2 metres per second - are not exactly reckless drivers.
Just like motor vehicles, AGVs have a set of indicators to show which direction they are about to travel. If the two lights are lit then they are going to keep going straight ahead, using their own laser sensors and sensors mounted on walls of the tunnel to help them navigate around.
“There are emergency stop buttons on the AGVs,” said Gordon. “If pressed, the robot will then cease to function. If an AGV is physically stopped by someone, then they have to be physically restarted again - they cannot start up again on their own.”
Far from stealing humans’ jobs, the AGVs actually allow flesh and blood workers to do what they do best - be human.
“The AGVs are designed to take on the heavy work,” said Gordon. “It frees up staff like porters and allows them to interact more with patients.”
Travelling down tunnels which stretch for as much as 600 metres, the AGVs push and haul food trolleys along them throughout the day for breakfast, lunch and dinner.
As well as making around 50 food deliveries in a 22-hour day, they also collect linen and general waste and have the ability to prioritise, making decisions based on the importance of the task they are carrying out - delivering food to patients is more important than dealing with general waste for instance.
There is no robot hierarchy operating here either, but it almost seemed like the AGVs were being polite or submissive when “Number 3” stopped dead and let “Number 6” go through the doorway first.
Gordon said: “They are all the same, there is not one who is above the other. That only happened because AGV 3 knows AGV 6 is doing something which has a higher priority.”
The current fleet of AGVs have an estimated life span of 10 years, but, like cars, it all depends on how well they are maintained.
Gordon said: “They have a set maintenance schedule just like any other vehicle. It’s based on the hours they work. They have a 500 hours service check and then major service checks every 3000 and 6000 hours worked.
“After a year the AGVs have just gone through 1000 hours worked.”
While their large size stops the AGVs being labelled as cute - even when schoolchildren land them with names like “Rupert” and “Betsy”, they do have a certain blue collar charm.
Just watching them for a short time is like a fascinating glimpse into the future - a future which is happening now in the lower levels of FVRH.
Gordon said: “See that one slow down as it comes to a doorway? That’s it making a decision on whether it is alright to proceed or not.”
It was a strange sight and something that, dare one say, made them seem a bit ... human.