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Ryan Chin and his colleagues are building the car of the future—a stackable, electric, shared two-passenger city vehicle that rethinks urban mobility. This work, in collaboration with General Motors, takes[…]

A conversation with the PhD student at MIT Media Lab.

Question: What is the CityCar?

Ryan Chin: CityCar is an electric two-passenger car that’s designed for shared use, meaning that it is not owned by any particular person. It’s a kind of community vehicle, so when you need this city car you swipe a credit card and it unlocks the door for these electric cars. When you’re done with the vehicle you just drop it off at another drop-off point. The CityCar itself is designed specifically for this use case in cities where there is not a lot of parking, a lot of congestion, so the goal of the CityCar is to reduce the number of private automobiles that are on the road. The CityCar itself is designed to fit this need, but also to be very compact, so when it’s being used it doesn’t take very much energy to move it around. It’s very lightweight. It uses in-wheel electric motors meaning that it’s very energy efficient. Each wheel has an electric motor. Each wheel has been given full freedom of 120 degrees of rotation, which means that the vehicle can turn on its own axis. It can part sideways into a parking space, all of the functions and features that you would need in a dense urban environment. The other thing about the city car too is that it can be compacted. It can be folded. It’s designed to be fit into a very small amount of space, so when the car is folded it only takes one-third of the space of a regular parking space, which dramatically changes the need for parking, but also changes the need for servicing and also where the locations are available to place this vehicle, so this vehicle is very, very different both in its use, but also in its design and its sort of layout.

Question: How is the CityCar a total departure from the traditional car?

Ryan Chin: The CityCar is very different than the traditional car. It’s much more lightweight. It only weighs about 1,000 pounds. A traditional car weighs about 3,000 pounds or even more. It uses an electric motor in each wheel. Most vehicles have a gasoline-powered engine. If it’s an electric vehicle it’s usually one electric motor that’s geared to all the wheels. In our case we have direct drive to each wheel, which provides us tremendous energy efficiencies. You don’t have to have a traditional gear box transmission for example and because of that we’re able to then create a new architecture, which allows us to fold and collapse the car. You don’t have to deal with the traditional driveline in the middle of the vehicle anymore. You have direct drive to each of the wheels, which then allows us to change the whole architecture of the vehicle and because of the folding we’re now able to get out through the front instead of the side of the car. Before there was a gasoline-powered engine, you don’t have that in the way anymore, so you get out through the front. When you have that then you have to start thinking about how you get in and out of the vehicle. You know do the seats articulate, which in our case they do. They help you to get out of the vehicle. Do have to have a steering wheel? No, we don’t necessarily have to have a steering wheel. When we’re looking at an omnidirectional vehicle that can go in any direction perhaps a joystick or other kinds of controllers are more useful. The in-wheel drive motors are driven by what we call drive by wire technology, which means that there is no mechanical connection between the steering wheel and the wheels themselves, so you can have by wire or remote control of the wheels themselves, which means that you can look at alternative ways of controlling the vehicle. No steering wheel, no pedals, no buttons, just joystick controls, which allows the freedom to make a very minimal interior. The vehicle now can be very, very compact in its use of components therefore, because the vehicle is very small you can actually have a lot of space because you’re not using those traditional elements, so the vehicle itself has all of these new technologies and in a secondary level you can imagine that the interior perhaps doesn’t even have traditional displays anymore, traditional analogue displays that provide speed and RPMs. It’s something that may not be necessary in cities. You know if you’re in the city you don’t care what your top speed is necessarily. You’re going to be in a traffic jam anyway, so that may not be important to you. The charge level may be more important to you or finding a parking space may be more important to you or finding a friend in an unfamiliar neighborhood may be more important to you. So the display of information will also be very different for the interior and possibly exterior. There are a lot of very interesting new technologies in displays where you can imagine the whole exterior of the vehicle being completely programmable, not only in a superfluous way where you say I want a pink car today and a blue car tomorrow, but perhaps in a very functional pragmatic way where you say it’s a very hot day out, perhaps the car should be white today and tomorrow when it’s very cold perhaps the car should be darker. I think the idea of making the vehicle very personalizable, even though it’s a shared use situation if you can personalize it electronically you’re going to make the car feel, not only feel and look, but also be driven in a way that is very personal to you.

The tires themselves for the city car are an integral part of the wheel unit. The wheel units we’re calling wheel robots, which encapsulate drive motor, suspension, braking, steering all inside the wheel and if you increase the envelope to include the tire you have a complete unit that snaps on and off the vehicle. Just imagine the wheel robot to be almost like a USB stick where you have power and data and some kind of connection to the body of the vehicle. If you can make that a modular unit you can service the vehicle very easily and in fact, we’re even looking at different types of tires that don’t require air and so we can create a completely dry wheel robot that doesn’t need to be serviced with all these fluids that you would see, for cooling perhaps or for braking. We can use the motor for braking. We can use the tires for even suspension. There is new interesting technologies developed in industry today that don’t require any air in the tire, so by removing all that burden of maintaining these elements you can have a very serviceable, maintainable wheel unit, almost like how you would build a computer. You would have all these different units that snap on and snap off for both upgradeability and also for serviceability and over time you can imagine that there could be even a whole economy based on these in-wheel motor units that different manufacturers would produce that can be driven down in price, but driven up in performance based on competition, so it will really change the way you may manufacture vehicles in the future as well.

Question: How safe is the CityCar?

Ryan Chin: The first thing to realize is that we all live already in a society where everyone mixes. You’ll have people walking on the street, people riding bicycles, an 18-wheeler, a kid with a soccer ball all on the street all at the same time, so that… You know we already live in a society where this is lots of different vehicle choices to be made and they’re mixing together. The second thing is that we can design a vehicle that is very safe even though it is smaller and the way to do that is in the architecture of the vehicle itself. The vehicle uses its in-wheel motors, which changes the whole architecture of the vehicle. It shifts a lot of the complexity to the corners of the car, which then means that we have freedom now to design a safety cage around the vehicle in a very different way, meaning that side impact can be taken care of in a much better way because now we don’t have side doors. We get out through the front of the car, so the apertures don’t exist anymore. We can design a safety cage that takes into account different kinds of crumple zones in the front of the vehicle because now there is no engine in the front. Now you can build a safety cage in a much different way. Our car folds, which means that you can utilize the folding as a dampening device during a front and rear collision as well and we’ve started to look at some crash safety simulations of the city car under those conditions and it turns out that when a rigid body crashes often a rigid body like a regular automobile when it crashes it also crumples in a folded manner, so we should utilize the folding to our benefit, not only as a way of compressing the car, but also decelerating the passengers in the cabin itself. So I think there is lots of sort of architectural moves in the design of the vehicle that allow much more safety, but that’s of course actual safety. 

There is also perceived safety, which is you know how do people feel about this vehicle? What are the features of the car that make it feel like it’s safe? Part of that of course is the look and feel. The other part of course is active safety, meaning putting sensors into the vehicle, making sure that you avoid and accident and not just you know make the vehicle survivable during an accident. So lane sensing, crash avoidance, active cruise control, all these technologies are being developed currently today. The third factor is the fact that this vehicle is a low speed vehicle. We are living in a sort of very dense and urban world now and this car is designed for metropolitan areas where the speeds are very, very low. In Shanghai today the average speed is nine miles per hour, nine to eleven miles per hour. It’s very, very slow, so that is another thing that you know to put into consideration is that this is not a high-speed vehicle. It’s not a top speed vehicle.

Question: What other transportation vehicles are you working on in the Media Lab?

Ryan Chin: We’ve also developed two other vehicles. One is called the RoboScooter. It’s an electric folding scooter. We did that with SYM, which is a scooter manufacturer in Taiwan. That vehicle, like the city car uses in-wheel electric motors and it’s very lightweight. It uses just one-tenth of the parts of a traditional gasoline powered scooter. It weighs half the weight of a traditional scooter. It’s about 90 pounds and again, it can be used in mobility on demand systems. You can imagine a mobility on demand network of these vehicles at charging stations where you can pick up and drop off the scooter. What we’ve also noticed in doing these studies is that in many places, particularly in Asia the pickup and drop off points may be different than they are in the West and in Europe. For example, in Taiwan they have the highest density of convenience stores in the world. 7/11’s are on every block, so you can imagine placing you know almost a scooter vending machine outside of every 7/11 and when you go to 7/11 you pick up a scooter or every convenience store that you go to or every donut shop that you go to here in Massachusetts. There are lots of donut shops. If you can imagine going to every one of these stations and picking up and dropping off that way. So what we’re trying to do is create a network that is looking for landing points in the city that are fairly ubiquitous, bus stops, convenience stores, schools. In Europe you know the Piazza is a great common gathering place. So I think that the scooter fits in very well because it’s very compact and it can fit into very narrow streets.

The scooter itself is something that we’ve been working on for a little bit of time now, about a year, year and a half and it’s quickly moving into production. In fact, we’re looking at production of scooters for the Chinese market pretty soon and we think that the key to the development of mobility on demand is to get the different vehicle types out there as quickly as possible. Each vehicle will have its different level of complexity in getting it out there as a product, so we’ve developed essentially an ecosystem. You have the car, which is the most complex vehicle. It has the greatest carrying capacity. We have the scooter, which is in the middle and then the last one is the bicycle that we’ve designed. The bicycle is called the Green Wheel Bicycle, Green Wheel Electric Bicycle. It’s an electric assist bicycle and so the idea is we’ve placed the in-wheel motor inside the hub of the wheel, just like we have for the other vehicles, but for a bicycle and the bicycle, the Green Wheel is an electric assist, so when you come to a hill you hit a button or a throttle control and provides electric power to the rear wheel, so it can help you to overcome the hill and it basically allows you to extend the range of someone that’s traditionally you know riding a bicycle, so you can overcome hills and go further distances. And the other key thing is that the Green Wheel is very modular, so it can fit in any standard bicycle, so you can take a regular bike, remove the rear wheel, put this new wheel unit in it and then now you have an electric bike. The controls are either on the handlebar or on the pedals of the bike and so that’s how you activate the wheel to be powered up and interesting thing about this is that it should open up the demographic of people riding bicycles, not just able bodied young people, but now seniors can ride. A couple that is a little bit older and one is… one of the couples is… has a hard time catching up, you can give that person an electric boost to be more social and to ride together. So I think that there opens up the whole demographic. Again, the Green Wheel like the RoboScooter and the city car can be used in mobility on demand systems and in fact, a lot of the existing bike sharing programs that exist today can be retrofit with the Green Wheel, so that you have some traditional bicycles and some that are electric. In fact, I think that’s going to open up so many more people to bicycling, which is one of the greatest inventions of all time is just the bicycle itself, a very energy efficient way of getting around in cities.

Question: Why are other countries already invested in electric bikes?

Ryan Chin: Electric bikes are very, very popular in China. They’re not being used in mobility on demand bike sharing programs. They’re just private use. In fact, China has already produced almost 100 million electric bikes in the last 10 years, so every year they’re producing 10 to 20 million electric bikes over 50% of which are for the domestic market, for the Chinese market, so that’s really you know taking off. In Europe electric bikes are very popular. In France, in Italy and also in Germany and in Holland you know almost 100,000 bikes being sold in… for the Dutch. So it’s really blowing up. In the US the market is small, but I think most people think of electric bikes as recreational and not basic transportation in the US, but I think that’s going to change dramatically, especially with these bike-sharing programs coming into play. Gas prices have changed a lot of behavior of consumers and at the same time there is a lot of gentrification of city centers now too, especially in the South. Louisville, Kentucky for example has a lot of people moving back into the center, reclaiming a lot of the sort of old warehouses in the city. There has been a big turnaround. Charlotte, North Carolina the same sort of behavior too, so I see the gentrification along with this movement and I think that there is actually a general too and you can see this in Japan where a lot of young people aren’t interested in owning cars anymore. It’s not cool to own a car anymore. It’s a burden to own a vehicle. I want to be more of a cool, hip young urbanite instead and that’s been a big trend as well. And of course those empty nesters are starting to move back into the city as well. This is a very common thing where you know kids have gone to college and we don’t need a big suburban home anymore. People are starting to look to move back into the city as well, so I think that’s a general trend. That’s a very Western trend. I think in the East and in Asia the urban densification is because of economic opportunity. That’s happening in Africa as well. Those two continents will be for the next 20 to 30 years where most of the growth will be in terms of population growth and the majority of that will be in cities, in dense urban areas and that’s primarily because of the economic opportunity there. 

Question: What will urban transportation look like in 50 years?

Ryan Chin: I think in the East Coast transportation will be pretty much the same. It will be very, very similar, primarily because we have lots of legacy costs and constraints because of legacy. I think the technologies will change. We’ll be electrified, much more electrified, but the road network won’t be very much different. The high-speed train, the apparent high speed train won’t be super high speed because of again legacy issues of being able to find straight shots from New York to Boston for example, but we will see the general electrification of vehicle transport. Public transit networks will probably be the same, very much so. They may have improvements, but most of the shift will be moving into hybrid and into electric charging technologies, especially for electric vehicles. What we envision in the Smart Cities group is eventually all parking spaces, not just garage parking spaces, but street parking spaces are charging stations, so whenever you stop the vehicle you’re picking up electric charge and the benefit of doing that is that you don’t to think about charging anymore. If you can just not have to go to a gas station or not go to a charging station, every time you stop the vehicle you’re charging the vehicle itself then you can reduce the overall burden of having batteries onboard. You can reduce that because then the range of the vehicle can be very short because most urban trips are very short and if you can pick up charge along the way that will be key.

In the far future you can even imagine wireless power transmission to the vehicle while it’s being moved, which is a very interesting concept that some people have already started to look at. Now I think it’s a little bit further out, but once you have that in place then the whole idea of having a place where you stop and charge doesn’t even need to exist anymore, you just pickup along the way and it doesn’t even have to be continuous. If you have some battery capacity onboard you can island hop, essentially go from one charged street to one that’s not and you know just have to make sure that the redundancy is there. That along with the emergence of autonomous driving and the combination of electrification will be the biggest change I see and one of the big challenges for autonomous driving is to scale down the size of all the computers that you see on some of these autonomous vehicles to something more reasonable and that’s one of the big things that I think will be the challenge for autonomous driving, but if that comes into play you can imagine that we probably will live in a very different world, although some of the structures will still be the same. If you think about Washington D.C. you know 50 years ago, it’s basically the plan is the same. You know there are a few minor alterations, but the technology has changed around it. Cities take a long time to change. Big Dig in Boston took 20 years to build. Just to submerge a tunnel underneath the ground, but changing the technologies I think can go much faster.

Question: What is the most difficult challenge Smart Cities is going to have to overcome?

Ryan Chin: I think the biggest challenge for our vision for Smart Cities is cultural, getting this thing out there and proving it to people and getting them to adopt these technologies. The burden of doing that will be in us being able to demonstrate this in reality, meaning building the vehicle itself, testing them out both in an individual vehicle, but also deploying pilot programs where you can try this out at small scale. I think once you have that in place that’s going to be the challenge. I think it’s the same challenge for most of the automakers too, which is doing these kinds of implementations. One of the fights that most of electric vehicle companies are having or automobile companies in general is they’re trying to make the car act like a traditional automobile. You’re taking a gasoline powered automobile, retrofitting it with an electric, so you’re basically replacing that and when you do that it’s very hard for battery technology to compare to the energy density of gasoline power and I don’t think that’s the strategy that we’re trying to deploy. We’re trying to reshape, rethink the way in which people use vehicles and then design it to be convenient to that and I think one of the challenges is when you design a vehicle. Today’s vehicle can be driven 300 miles, but most people don’t ride 300 miles. The average American drives maybe 40 miles. 80 percent of Americans drive less than 40 miles, so if you design a vehicle that is 80 miles in range that’s all you would need, so you’re carrying all this extra stuff around, so that’s the sort of traditional model. I think we’re getting around that problem and the bigger problem will be not the technology itself, but the adoption of these technologies and making sure that the technologies themselves are simple to use. That will be one of the key things. You don’t want to have a very complex new system where people can’t figure out how to use it and that you can prove by piloting these programs in cities in which you can get great impact, but also are progressive enough to adopt these new programs.

Question: What role will aesthetics play in the future of car design?

Ryan Chin: I think aesthetics are key. You really need to have a good eye for these types of things. A good example is the iPod. iPod is an MP3 player just like any other MP3 player and it was designed with design in mind, aesthetics in mind. It’s a very simple design. Most people find it attractive as a device and it’s no longer thought of as an MP3 player. It’s thought of the iPod and so we have to approach this design of the vehicle in the same way. When someone is using a car in the city it’s not just to get from A to B. It’s to look good. It’s to feel good. It’s to be stylish as well. So these vehicles have to be designed with aesthetics in mind and part of that is to blend into the city correctly as well. If you take a photograph of our design in a city and it doesn’t feel like it fits it’s probably not going to be accepted at all and I think philosophically this is also where I disagree with a lot of the bike sharing programs today. A lot of the bike sharing programs design very heavy, ugly bikes primarily because they don’t want people to vandalize them, but that’s one of the reasons why not many people are adopting them because they’re ugly and heavy. If you make a very beautiful bike or a very beautiful car perhaps you mitigate some of the vandalism, perhaps you will have more people adopt it because it’s very cool to be in one of these vehicles.

Question: How will you take into account varying climates?

Ryan Chin: Yes. I think it’s going to be important to be able to customize the vehicle for different climate situations and different terrain situations. The vehicle itself should work very well in winter climates because it’s all wheel drive vehicle, has 360 degree steering, so it has very torque at low end as well, so I think the driving performance should be fine in those situations. In colder climates the battery will not perform as well as warmer climates, so that’s one thing to consider. Rain, sleet, snow is another key area. These vehicles should be air conditioned as well and one of the ideas that we’re experimenting with now is to be able to preheat and pre-cool the city car, meaning that if it’s very hot out you should walking into the vehicle and it’s already at ambient temperature and one of the problems is if it’s very warm out and you get into a car that’s very hot you instantly blast the a/c to get it cool or in an opposite situation, when it’s very cold out you put the heater on. That drains the battery a tremendous amount, so with mobility on demand you have the capability of preheating and pre-cooling at the station because you already have placed the infrastructure there for charging, so if you’re plugging in the vehicle anyway you might as well control the temperature inside and that I think is a plus just from a comfort level point of view. So I think that there is going to be a lot of consideration on the climate based on those types of philosophies.

At the same time manufacturing the vehicle should really be regionalized as well, so the wheel robots can be mass produced, optimized for those different conditions and you know to drive the cost down, but at the same time you can then assemble the vehicle in different ways where you have regional manufacture of some of the key components other than the wheels themselves, so the interior, the exterior cladding for the vehicle. There may be different crash regulations in different parts of the world, especially Europe and Asia and so you want to be able to regionally manufacture those and not waste transportation costs and then snap them all together, so you can imagine a whole network of sub manufacturers that do this assembly in a very local, regional way and that meets the needs of that particular region and then you have this sort of mass producer that produces the standardized components of the vehicle that can either be shipped or can even made regionally as well. So I think the responsiveness should be there.

Question: Which cities could emerge as early adopters when it comes to Mobility on Demand systems?

Ryan Chin: The city of Paris, the city of London have already adopted very progressive policies when it comes to energy efficiency and sustainability. They have also road regulations as well. The city of Singapore has one of the best transportation networks in the world. In fact, they want to look aggressively at new technologies because they actually consult other cities on how to layout their transportation network, so I think Singapore is a great case. Some of the East Coast cities and West Coast cities of the United States where you have a lot of the innovation and you have a lot of young people, a lot of colleges where early adopters can join in can also be great sites for this and that could be New York, Boston, Chicago or even San Francisco, cities like that. Especially San Francisco where there is a desire to be green. City or Portland is another great city. There are a number of smaller cities that could also do it too. I think of Boulder, Colorado as a very progressive city, which already has a smart grid as well, so can identify cities that already have sort of invested in this, but again, the need for both business and political will has to be there to adopt these systems, to get them out there, to acquire the land to put the mobility on demand systems in place. Cities that already have both public transit networks, basic ones, but also local pollution is also a big driver too, so if you see the smog everyday you probably will want to change it more than the city that doesn’t have it. A good example here is in Boston. You know we do have local pollution, but it’s all swept out into the ocean, but in L.A. it’s in the basin and so you see it every day and you want to change it and there is a lot of cities like that as well. One particular city that has one of the greatest pollution problems is Kaohsiung, Taiwan, which is the most southern city in Taiwan. It’s the second largest city in Taiwan. They are the most polluted city in Asia and that is because most of the heavy industry of Taiwan is based there and they’ve just recently adopted a bike-sharing program themselves and they’re looking at these other programs to really compete with the other cities in Asia. So I think that the cities that may adopt this come in all different sizes and are all different places in the world.

Recorded on January 21, 2010