도서요약

Urban Mobility Takes Off

Suddenly, the 21st century world envisioned more than fifty years ago for the fictional Jetsons family seems closer than anyone imagined. While cost-effective service robots will probably be focused on eldercare and hazardous situations for the next twenty years, commuters could end up flying to and from their jobs much sooner.

According to a new NASA concept study, taking a ride in a vertical-takeoff-and-landing (VTOL) air taxi could become as cheap as taking an Uber ride, and get you where you’re going in less than one-third of the time.1

In fact, it’s the combination of an Uber-like ride-on-demand business model with state-of-the-art drone technology that just might provide the best model for making the economics work.

As Mark Moore, chief technologist for on-demand ?mobility at NASA’s Langley Research Center observed during a presentation at the recent SAE AeroTech Congress and Exhibition in Seattle, “Uber could provide a true door-to-door system. It’s hard to beat that economic model.”

Moore’s presentation was part of a status report on “flying cars,” also known as roadable aircraft, hybrid air systems, or air taxis.

Moore and his colleagues analyzed scenarios focused on Silicon Valley and extending from Oakland to San Jose. In this environment, air taxis could realistically match an Uber benchmark of $1.50 per mile traveled at an average ground-speed travel rate of 34 miles per hour for urban areas. While that still sounds slow, it equates to a 250 percent improvement over the average Silicon Valley rush-hour travel speed.

For longer trips, passengers will benefit from cruising at 120 to 200 miles per hour or more once the vehicle reaches an altitude of 2,500 to 5,500 feet.

How would this revolutionary system actually work? Here are seven key assumptions:

1. The study assumes the development of a new kind of vertical-takeoff-and-landing aircraft, powered by electrically driven propellers. This so-called “distributed electric propulsion” (DEP) technology is already being prototyped as part of NASA’s LEAPTech initiative. It’s also being explored by an assortment of commercial ventures.

2. To provide enough range, the study assumed the aircraft would use next-generation batteries with at least twice the energy density that’s currently commercially available - around 400 watt-hours per kilogram. In 2016, the British firm, OXIS, plans to start producing batteries based on lithium-sulphur technology, which are expected to meet this requirement at a very attractive price point.

3. There’d have to be a takeoff and landing infrastructure to support all those “Uber Air” flights. The NASA study suggests putting helipads on the roofs of urban buildings, in the middle of highway cloverleafs, or even on floating barges. Researchers estimate that there’s room for at least 200 cloverleaf pads in the Silicon Valley region targeted in the preliminary research.

4. The Federal Aviation Administration would have to sign off on regulations for all those added flights. NASA’s study confirmed that the helipads could be built to fit the FAA’s clearance restrictions.

5. To minimize costs, NASA’s model calls for aircraft capable of carrying a pilot and one passenger. That single passenger model describes more than 70 percent of the trips currently conducted by Uber, as well as about 80 percent of other commutes. But notably, the pilot is likely to be optional; UAV technology already exists for autonomous vehicles without pilots, and it’s technically much simpler than a self-driving automobile.

6. The Uber-style business model is key to making the economics work: NASA’s study assumes that each air taxi would be in the air 1,500 hours a year, or roughly thirty hours per week. That brings the cost down to $1.50 per mile at 34 miles per hour. This equates to a total ownership cost of $76,500 per year, which makes sense for a pilotless autonomous vehicle.

7. Moore said the noise factor is the “most severe constraint” for commuter air taxis. If those next-generation aircraft are as loud as present-day airplanes or helicopters, the idea literally won’t fly. However, NASA says the motors for an aircraft powered by distributed electric propulsion could be arranged to create acoustic interference, resulting in low noise levels. It’s the same concept that makes today’s noise-canceling headphones possible.

NASA is already developing and demonstrating DEP technology. However, commercializing the concept will be left to private ventures such as Joby Aviation and e-volo. Let’s consider the latest innovations from these two firms.

Joby Aviation’s S2 aircraft design embodies all the characteristics needed to realize the air taxi concept. Since the primary noise, safety, and energy issues arise during takeoff and landing, Joby has incorporated twelve retractable propellers into the S2’s design.2

The propellers are powered by electric motors for vertical takeoff and landing. Once at cruise altitude, the S2 uses just three pusher-props.

Rapid progress over the past decade in direct-drive electric motors and efficient motor controllers has resulted in light, powerful, and reliable motors that will provide the propulsion to make the dream of personal electric aircraft a reality.

According to Joby, redundant control systems and sensor technology developed for smart phones make it possible to build a robust electric VTOL aircraft capable of transporting people more safely than an automobile. At this point, Joby plans to use lithium nickel-cobalt manganese-oxide batteries.

Meanwhile, e-volo’s EC200 Volocopter is a revolutionary two-person air vehicle from Germany.3 It’s less sophisticated than Joby’s, resembling a scaled-up children’s toy.

But it has the advantage of already flying as a prototype. With eighteen independent electric rotors, the EC200 is safer, simpler, and cleaner than normal helicopters.

At an altitude of 6,600 feet, it reaches a cruising speed of 100 kilometers per hour and has a range of over 100 kilometers. Future versions of the Volocopter are expected to achieve higher speeds and longer ranges.

When it comes to the economic model for such air taxi services, Moore told Geekwire that British Columbia’s Helijet is already blazing a trail with its Vancouver-to-Victoria service. He said that, like Silicon Valley, the increasingly congested Seattle region is especially well suited for next-generation air taxis.4

Both areas have severe geographic water and ground constraints that are easily circumvented with aerial solutions, as well as lots of affluent consumers, high housing costs, and good weather.

Given this trend, we offer the following forecasts for your consideration:

First, the air taxi industry will come to symbolize the Digital Techno-Economic Revolution just as automobile taxis and commuter trains symbolized earlier revolutions.

This concept is only practical now because of the convergence of the sharing economy with lightweight materials, precision GPS, high-performance electric motors, noise-canceling technology, inexpensive sensors, and AI-based control systems.

Second, the emergence of the technologies needed for the air taxi industry demonstrates where government spending can provide maximum value to society.

NASA’s LEAPTech Direct Electric Propulsion initiative and Germany’s sponsorship of critical work on the Volocopter illustrate why research funding is a crucial activity that we can’t afford to eliminate even as we redefine the role of the federal government (as discussed in our first trend this month).

Third, while it appears that next-generation batteries will meet the needs of the air taxi industry, shortfalls in this area will not be showstoppers.

Fuel-cell technology with far better power-to-weight performance already exists, and both Honda and Toyota will be mass-producing such power plants, shortly. Hydrogen for this purpose could be stored as a liquid, compressed gas, or simply reformed on-board from methanol. From a clean energy perspective, new low-cost catalysts will soon make hydrogen generation from sunlight and water cost effective.

Fourth, cost-effective air taxi service will dramatically impact commuting for tens of millions of people in the OECD by 2030.

Each year, billions of frustrating person-hours will be transformed into productive work time as well as leisure. Increased highway congestion will be avoided. People will arrive at work more refreshed and ready to maximize their contributions.

http://www.businessinsider.com/nasa-study-says-air-taxis-uber-of-future-2015-9?pundits_only=0&get_all_comments=1&no_reply_filter=1

http://www.dailymail.co.uk/sciencetech/article-2618915/The-future-flight-Helicopter-plane-hybrid-battery-powered-doesnt-need-runway-takes-VERTICALLY.html

http://www.wired.com/2015/06/18-rotor-volocopter-like-flying-car-better/

http://www.geekwire.com/2015/nasa-study-flying-air-taxis-could-be-as-cheap-as-an-uber-ride-and-faster/