Authors: Bern Grush, Lee St. James
January 29, 2024
Automated vehicle technology being developed for cars and delivery robots is finding its way into shared-utility wheelchairs and single person autonomous mobility pods. Today such robotic wheelchairs are increasingly being deployed in airports and hospitals and are likely to find a role in entertainment parks, shopping malls and museums to help people who struggle to walk long distances within these public environments.
Owing to an aging population and sedentary lifestyles, an increasing number of individuals face challenges walking long distances in places like airports and shopping centers. Leveraging insights from mobile robots in factories, automated vehicles, and delivery robots, integrating these innovations into wheelchairs offers impactful solutions to the growing demand for occasional and place-specific mobility assistance.
Wheelchair Assistance in Airports
The 1986 U.S. Air Carrier Access Act (ACAA) requires airlines to provide free wheelchair service to any traveler who asks for it, without requiring a description or documentation for that need. Passengers often face long wait times for wheelchair assistance as airlines are having trouble keeping up with demand. Airport labour shortages are exacerbated by rapid increases in requests for mobility support.
Special Service Request (SSR) codes are used to identify the type of assistance travelers require, with the WCHR code representing the largest subset. A WCHR request involves assisting the passenger from ticket gate to departure gate, including through security. A WCHR passenger is someone who requires a wheelchair to and from the aircraft but can walk up/down stairs and can manage in the cabin unaided. A robotic wheelchair can be used to satisfy the requests for WCHR passengers.
According to accessible air travel expert, Roberto Castiglioni, the global rate for assistance requests stands at an average of 1.2%, varying by location, with some large EU airports exceeding 2%. This means that, on average, 1.2% of passengers are requesting wheelchair assistance. According to Airports Council International's (ACI) September 2023 industry outlook, global airline passenger traffic is expected to reach 9.4 billion in 2024.
The U.K. Civil Aviation Authority reported over 1.7 million WCHR requests, reflecting 54% of the total 3.2 million assistance requests in 2018, the latest year for which figures are available. Applying the 54% WHCR portion to the 1.2% assistance request rate and ACI’s estimated 9.4 billion air passengers in 2024, suggests a potential 61 million WCHR requests worldwide in just one year — a considerable market opportunity for wheelchair robots.
According to Tres Izzard, President of WHILL Mobility Services North America, air traffic is increasing 3-5% per year, while wheelchair requests have been increasing between 15-25% per year. He points out, for example, that Miami International Airport regularly receives over 4,000 daily wheelchair assistance requests. Addressing this demand, his company provides autonomous wheelchairs for many of these requests.
Hubs of large airlines routinely run wheelchair operations up to 21 hours a day, amounting to 147 hours per week. Considering full-time wheelchair pushers working a 37.5-hour week, four wheelchair pushers could cover 150 hours in a week. So, one autonomous chair, with its human overseer/teleoperator/handler, can effectively do the work of roughly four wheelchair pushers.
Factors driving assistance requests include disability, long walking distances, help with bags, and wayfinding difficulties. And requests are growing. The demand for mobility assistance is heightened in countries with aging populations, extending beyond air travel to hospitals, museums, and shopping malls.
UPDATES: 1) Our readers might find this article of interest (published Feb 12, 2024): https://www.airport-technology.com/comment/senior-travellers-are-back-and-airports-need-to-be-ready-for-them/
2) Cyberworks Robotics reported on their successful pilot at Gerald R Ford International Airport: https://www.linkedin.com/posts/cyberworks-robotics-inc_autonomousmobilerobots-cleaningrobot-autonomousrobots-activity-7177306148742606848-PBor (March 23, 2024)
Hospital Trials
Vivek Burhanpurkar, CEO of Cyberworks Robotics recently completed a three-year trial at the Toronto General Hospital, designed for moving patients through a multi-stage diagnostic process. The pilot project was designed to ensure that hospital staff knows where the patient is, and the patient finds their way to the next station—a form of workflow.
Autonomous wheelchairs for hospitals and other public spaces like airports pose a unique challenge — there is no margin for failure or what are known as "edge-case" challenges. A single navigation failure could be catastrophic for the vulnerable passenger of such a chair.
To address this challenge, according to Burhanpurkar, Cyberworks Robotics spent nearly a decade in stealth development to create a host of 'aviation grade' safety features including a black-box recorder, an automatic self-recovery technology for non-fatal transient hardware anomalies, and, most importantly, a radically new redundant autonomous navigation framework with an interesting advantage over outdoor navigation: “Our navigation system, SkyLane, use features in the ceiling as a redundant source of landmarks. This greatly facilitates Cyberworks navigation confidence.”
How they work
There are three predominant methods to move a robotic mobility device from one point to another in a large but bounded space such as from a hospital admission desk to a specific medical department on a distant wing:
Teleoperation. A remote human operator using the cameras and sensors on the wheelchair or pod can navigate the device using a joystick or similar control.
Path memorization. A digital map provides a number of pathways for a mobility pod or wheelchair to proceed while following the rules to give way to other users of the pathway and to be able to independently divert slightly from the pathway in the event of an obstacle (let’s say someone left their luggage standing on the pathway).
Self-navigation between waypoints. Specific points are marked on a pathway and a wheelchair or mobility pod moves through a sequence of such points while working out its own pathway between them. This is somewhat analogous to a delivery robot that can find its own pathway along a sidewalk as it moves from one intersection to another (the specific waypoints), but reorients itself or may even need help at an intersection.
Both WHILL and Cyberworks rely predominantly on the latter two methods, using teleoperation from a 'command centre' as an oversight and backup. For large indoor applications this makes most sense – the number of possible pathways is bounded and the pathways remain relatively constant.
Public-area mobile robots
Unlike advanced wheelchairs such as the iBot from Mobius Mobility, which is owner-operated, robotic wheelchairs are classified as a public-area mobile robots (PMR) when they are used in a service to transport a human passenger within a public environment. In these use cases, robotic wheelchairs provide greater access, independence and assured navigation to people in unfamiliar environments.
Two of their primary application domains are airports and hospitals, but these robots will also find applications in retirement homes, on school and work campuses, at workplaces or transportation hubs, in museums, or in entertainment parks such as zoos, and historical sites.
“I see the technology as impacting anyone who is confined in their motions, so I see it applied in hospitals, in retirement communities, and in assisted-living communities,” says Daniela Rus, Professor of EE&CS, MIT (2017 video clip at https://www.wired.com/video/watch/autonomous-wheelchair)
A current limitation is that these robots are preprogrammed with a set of user-selectable “trips.” For example, it would know its way from the airport ticket gate to each departure lounge, or from a hospital admissions desk to each waiting area in each of its wings. For the all the types of applications listed, a limited set of such journeys — say many tens — would provide considerable value within these limited, structured environments.
And that is changing such that the menu of available trips, the flexibility during a trip—for example to take a detour to purchase food, to use a washroom, or to change the order in which a museum or zoo visitor wishes to visit exhibits —will continue to be enhanced as the interfaces mature from touchscreen to natural language.
Robotic Wheelchairs are in a unique category
Robotic wheelchairs are of particular interest to the Urban Robotics Foundation in our mission to maximize the social value and acceptability of public-area mobile robots. There are several reasons these devices are distinct amongst all of its PMR cousins such as delivery, security, and maintenance robots.
Demand will grow due to demographic change. Assisting seniors and people with mobility impairments to move within large, public facilities is growing increasingly important for two key reasons. First, ageing populations, common worldwide, mean that more people need assistance. Second, ageing populations mean that there are declining labour pools to provide that assistance.
Automating wheel chairs for indoor navigation in public facilities will usually be more difficult than navigation in warehouse or factory applications but will often be more easily achieved than for many outdoor delivery, security or maintenance applications.
Socially, autonomous wheelchairs are more naturally inclusive than the popular delivery robot, which may sometimes experience lower acceptance among the disability community. Such robotic wheelchairs will experience little or no social pushback compared to other forms of PMRs.
The need for wheelchair robots is virtually unquestionable, especially in airport and hospital environments. In larger facilities, the distance that must be travelled within those facilities can be taxing for a senior or a disabled user. Equally important, when a user is experiencing a facility for the first time, the challenge of navigation can be reduced by using an automated wheelchair loaded with a pre-planned route.
Robotic wheelchairs have a very low labour displacement index compared to perceptions about other forms of PMRs. There are already labour shortages even as demand increases.
Robotic wheelchairs address critical mobility issues for its user population giving them highly positive ethical attributes.
Robotic wheelchairs have a lower demand for teleoperation, compared to many delivery, security, or maintenance robots. This means lower risk from teleoperator variability and lower operating costs which in turn means more access for users who need the service.
Taken together, the social value of robotic wheelchairs may be as high or higher than the social value of any other form of PMR. What this implies is that anyone experiencing the benefits of these robots would be more inclined to see them as accessible and robotic wheelchairs will contribute to the social acceptability of the entire PMR category.
NEXT STEPS
For information about various use cases of public-area mobile robots and how to prepare for deployment in your city or public facility, the Urban Robotics Foundation offers a series of guides and workshops. Our complimentary 2024 Executive Guide to PMRs is now available for download from: https://www.urbanroboticsfoundation.org/guidebooks
References
1. Baltazar, A., Petry, M., Silva, M., and Moreira, A. (2021) Autonomous wheelchair for patient’s transportation on healthcare institutions.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7898257/
3. MIT (SMART; hospitals) https://www.youtube.com/watch?v=pRo8FnS2XfY
4. Whill robot (airports) https://www.youtube.com/watch?v=pkx8PoUZWo8
5. E-wheelchairs: https://www.youtube.com/watch?v=ZSEI0Fdf6y8
6. 10 E-wheelchairs: https://www.youtube.com/watch?v=Ulw-osYVuMk
7. Whill at JFK: https://www.youtube.com/watch?v=_MB6y-2X2Qs
8. Drove (Control Bionics): https://www.youtube.com/watch?v=XaSuMlTb4H0
10. Cyberworks: https://www.youtube.com/watch?v=FOJSZaVM7xg
11. Cyberworks UHN: https://www.canhealth.com/2023/10/31/smart-wheelchairs-to-take-patients-to-imaging-suites-being-tested/
16. https://aci.aero/wp-content/uploads/2023/01/2.-Incheon-Airport-Autonomous-People-Movers_final.pdf