The need for companies to change their ways

XVI.1 January + February 2009
Page: 48
Digital Citation


Eli Blevis

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If you are at all concerned about the environment or even just worried about the rising cost of gasoline, you've probably wondered about the realities and promises of electric, hybrid electric, ethanol, biodiesel, propane (LPG), natural gas (CNG), hydrogen, even compressed air, and other alternative vehicle power technologies. There's another pair of alternatives you may or may not have considered—human-powered vehicles (HPV) and hybrid electric-assist human-powered vehicles. An HPV or perhaps an electric-assisted HPV—the other hybrid—may be in your future.

back to top  Forms of Human-Powered Vehicles

HPV might seem like a fancy term for a bicycle, and it is. Nevertheless, there are a lot of HPVs that appear to be coming into their own, ones that go well beyond what you might think of as the upright two-wheeled form of the common bicycle.

Recumbent bikes. A bike is recumbent if you ride it in a seated position, legs forward rather than beneath you. Recumbent bikes are a bit odd looking, but they are more comfortable and more aerodynamically efficient than upright bikes. The recumbent design is in no way new, but there is a renewed interest in recumbent bikes.

Delta trikes. A delta trike has three wheels, one in front and two behind the rider, who takes a seated position. You probably associate delta trikes with small children, but there are some very sophisticated—and expensive—designs now available that would make wonderful commuting vehicles, notably the Kettwiesel line from Hase ( Like recumbents, delta trikes are very comfortable and have the added advantage of stability. Also, the rider does not have to remove her or his feet from the pedals when stopping.

Tadpole trikes. A tadpole trike also has three wheels, but two in front and one behind the seated rider. Tadpole trikes are generally lower to the ground than delta trikes and more aerodynamically efficient as a result. On the downside, they are much less easily visible to cars, and their proximity to the ground may make them more difficult for older riders to "mount" and "dismount."

Fairings. A fairing is a partial enclosure mounted commonly to the front of an HPV, which offers protection as a windscreen from adverse weather conditions, as well as offering oftentimes substantial improvements to aerodynamic efficiency

Velomobiles. Fully enclosed HPVs are velomobiles, which are usually based on tadpole trikes and are often available with electric-assist motors. These machines can be very sleek—the go-one ( and the aerorider ( are some "sweet ride" examples. A comprehensive list of these machines appears at The stability of a trike, the weatherproofing of full enclosure, and the benefits of exercise are among the most attractive elements of velomobiles. As for downsides, they include the expense of being an early adopter and the safety issues of being in a vehicle that is low to the ground and barely visible to cars.

If you are lucky enough to live in a city that already embraces bicycles, much of this is probably not news to you; you may have already seen all of these HPVs. If you don't live in such a city, these HPVs may be part of the recipe for changing the place you call home into an HPV-friendly and environmentally friendly area. It's possible that one of these alternatives could make commuting under your own power a more attractive option. When enough people find an option attractive, city governments will hopefully react accordingly.

If you think that HPVs are just too slow, you might find it interesting that HPVs and their riders can reach land speeds of more than 50 mph (judged from a standing start over a one-hour duration), according to the U.S. Human Powered Vehicle Association (HPVA; and the International Human Powered Vehicle Association (IHPVA; Of course, your own results may vary.

back to top  Electric-Assist Systems

You don't need to be an athlete to consider commuting by HPV. Many forms of HPV now come with optional electric-assist "hub motors," which can be used "full throttle" or as an assist when riding uphill and from standing starts. Such systems let you balance the benefits of exercise with commuting via HPV and the need to arrive at work in dry clothes.

The 100-year-old-plus Heinzmann company offers complete electric-assist bicycles and kits that can be used to convert existing bikes to electric-assist configurations ( The BionX system also offers electric-assist kits that include digital display controllers, varying rider-selected levels of assist programs, and the ability to regenerate power while coasting and braking ( There are many other such systems available, including some that are designed to work in industrial and commercial light electric and HPV applications (for example,

back to top  Issues and Opportunities for Interaction Designers

In a perfect world, one could just switch infrastructures to accommodate changing needs and new, greener technologies. Sadly, this isn't a perfect world. HPVs need to be integrated into existing transportation and social infrastructures. There is a role for interaction designers in creating this integration.

First, interaction designers can design interactivity to motivate ordinary people to adopt environmentally friendly alternatives like HPVs. This may be accomplished through the myriad social channels afforded by present information technologies and others that are yet to be imagined. For example, someone in our community could design a carbon-footprint calculator that helps people see the benefits of changing to HPV commuting, plan HPV-friendly routes, and understand the financial benefits as well as the environmental benefits of such a change. The health benefits that accrue from increased exercise are another issue, one that is an important but much less emphasized aspect of sustainable ways of being.

The use of computers on bikes appears to be mostly limited to measurement tools for athletes. Much more could be done to make HPVs more attractive to commuters and others. You can mount a GPS device to your HPV—GPS devices with settings for bicycles are available—use Bluetooth to enable hands-free speakerphone functions, and have embedded mp3 players. Our community has studied such devices for cars somewhat extensively, especially with respect to issues of cognitive overload, but the issue of how such devices create benefits and problems in the HPV context needs to be studied. Moreover, we could be the designers who call for making HPV systems that integrate gauge, controller, and battery systems into single integrated systems—from the assist motors to lighting systems to HPV-specific GPS devices to mobile communications that work in the wind. Some systemic thinking must take place to make HPVs practical for ordinary folks.

Some other issues to which interaction designers may wish to direct attention include understanding the relation of weather to HPVs. What constitutes "safe" weather for HPVs? How can interactive technologies be used to make riders aware of weather limits, and can such technologies be employed in a personal and mobile way? Yet another issue is the ways in which HPVs interact with public transportation systems. How can interactive technologies be used to manage such interactions? Is there a future in which you will be able to ride your velomobile to the train station or airport? Will you be able to take your velomobile along? There is an opportunity to design interactive systems to help with HPV-specific parking location and safe route planning while on the road.

One of the most important issues is safety. Wide adoption of various forms of HPVs implies a wider variety of vehicle sizes and types and nominal visibility, speed, and braking capabilities sharing the same pathways than ever before. Perhaps there is a role for interaction designers in understanding and reshaping social attitudes between drivers, riders, and pedestrians in a manner that motivates safe and courteous behaviors.

A detailed example follows.

back to top  Safety and Signals

Let's take a look at one of these issues and opportunities in a little detail. Suppose you're riding your velomobile to work and you arrive at an intersection with a red traffic light. Furthermore, suppose that four cars are lined up at the intersection. Also, assume that there is oncoming traffic, which may turn left when the light turns green. Finally, assume that you are in a country where cars drive on the right side of the road. Do you:

  • A. Go onto the sidewalk to pass the stopped cars?
  • B. Pass the cars to the right staying on the road?
  • C. Pass the cars on the left?
  • D. Stop behind the last of the stopped cars, close to the curb?
  • E. Stop behind the last of the stopped cars, centered behind the last one?

If you choose A, the problem is that you become a menace to pedestrians, and furthermore, you run the risk of being hit by a car turning right at the intersection since drivers aren't used to paying attention to things that move fast on sidewalks.

If you choose option B, you run the risk of being hit by a car that attempts to park, or turn right, or is too close to the curb. On an upright bicycle, the car may see you in its passenger-side mirror. On a recumbent, there is much less chance of a car noticing your approach from behind, especially on a tadpole trike or velomobile.

If you choose option C, I'm really worried about you.

If you choose option D, you run the lesser but almost certainly lethal risk of being squashed if the last of the cars decides to back up for any reason. If you are on a tadpole trike or velomobile, there is little chance that the last of the cars knows you are there.

If you choose option E, you increase the possibility that the last car will notice you only by a little, but you make it easier for a car approaching from behind to notice you and respect your position in the line of stopped vehicles. Option E is often advised for upright bikes, but on an HPV that's low to the ground, you have the added problem that even if all of the stopped cars have noticed you, the cars approaching the intersection from the other direction cannot see you at all. If a car at the intersection travelling in the opposite direction is waiting for the car ahead of you to pass through the intersection before turning left, it is unlikely to notice or wait for you to go through the intersection before it does so.

There are no good options, and that is a problem.

The interaction design problem that emerges is one of figuring out how to make the various commuters aware of one another's locations and intentions in an infrastructure shared by vehicles of various sizes and degrees of insulation from the environment. With a fresh infrastructure, the problem is easier—simply have three lanes and three types of traffic signals, one each for regular vehicles, one for HPVs, and one for pedestrians. Such infrastructure exists in some cities—Eindhoven in the Netherlands is a good example. More commonly, where such infrastructure does not exist and in the presence of our three or more classes of travelers, there needs to be a system of signaling that works in the shared space. Such a system might incorporate mechanisms of augmentation for hand gestures and eye contact, LED lights, RFID tags and sensors, sensors that connect to in-vehicle displays, and other mechanisms of awareness. The design of such systems—my mellow velo friends—is an opportunity for interaction designers to help save the day, and perhaps the planet.

back to top  Author

Eli Blevis serves on the faculty in the Human-Computer Interaction Design program of the School of Informatics at Indiana University, Bloomington. Dr. Blevis's primary area of research, and the one for which he is best known, is sustainable interaction design. This area of research and Dr. Blevis's core expertise are situated within the confluence of human computer interaction as it relates to the computing and cognitive sciences, and design as it relates to the reflection of design criticism and the practice of critical design. Dr. Blevis has published more than 40 articles and papers and has given several invited colloquia internationally on sustainable interaction design and the larger context of notions of design.

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back to top  Figures

UF1Figure. Image provided by Go-One LLC.

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