DULUTH — A robot was parked among the humans waiting for an elevator during a tour of Essentia Health's new hospital earlier this week. Even before it arrived, the L-shaped machine, likened by staff to a Roomba vacuum cleaner, rolled itself forward and turned to face the elevator doors.

The bed of the robot, where it carries things such as fresh linens and garbage, was empty. It was just a practice run, but when the new facility opens to patients on July 30, there will be a staff of 24 Tug robots ready to perform chores autonomously throughout the buildings.

"That's all to maximize the time of our staff on the side of the patients," said Dr. Robert Erickson, the lead physician for the Vision Northland project. "So, we're really looking forward to that."

The robots are among the technological highlights of Essentia Health's new state-of-the-art 942,000-square-foot St. Mary's Medical Center.

This week has been a ceremonial one as the public gets its first look inside the horseshoe-shaped, largely glass structure that has drastically changed Duluth's cityscape. The four-year project cost $915 million — the largest private investment in the city's history — and the process will culminate when patients and their beds are rolled through the skyway and into their new rooms at the end of the month.

There is efficiency in its very shape, which is upward more than outward. There are are 18 floors serviced by 28 smart elevators. These lifts group riders according to their destination floor, so there are fewer stops in between.

"The design element is that vertical transport, and the transport of patients and material, is more efficient than horizontal," Erickson said.

The robots, too, are looped into the system. A food delivery run won't share space with a garbage collection.

There are navigation kiosks with touch screens that synch to a phone app, like at a mall.

Essentia Health ditched its designated visiting hours months ago; guests are free to come and go at will. The new rooms are single-occupancy and equipped with visitors in mind, with mini refrigerators and pull-out couches. Each has an entertainment system capable of running streaming services or ordering meals. Supply shelves are accessible from the hallway, so they can be refilled without disturbing a patient.

The rooms are standardized — everything is in the same place from unit to unit. And in the natural birthing unit, the space that is void of obvious medical equipment has medical gas hookups hidden behind framed art.

In the early phases of the project, 26 user groups went over the room designs to determine what should go where for the most efficient use of space. Since then, care teams have gone through the rooms with a "fine-toothed comb," to make sure they have everything they need, according to operations director Jill Cernohous. The equipment has been tested; preparations have been made for a variety of hiccups — such as a power outage.

When COVID-19 hit midway through the project, those behind Vision Northland were tasked with reconsidering how to adapt for the future. The oxygen pipes infrastructure was upsized, according to Dan Cebelinski, director of facilities. It is possible to bring in 100% outdoor air through the tower.

The new facility is described as a 50-plus-year building, designed with flexibility in mind so it can change with advancements in medicine.

The new emergency department is 25,800 square feet of space with 40 private beds. Many of the tools needed are within the room, including CT, X-ray and ultrasound machines. There is a high-speed elevator that will bring patients who arrive via helipad directly into the emergency department.

There is also room for growth. There are five floors of space on the Superior Street side that can be used for the "clinic of the future," Erickson said. There are two floors in the hospital that can be converted to an ICU in a pandemic.

After patients have moved from the old hospital, it will be cleared out and likely demolished by September 2024, according to Cebelinski. The future of that property has not yet been decided.