Petal Velomobile by Eric Birkhauser

Architect Eric Birkhauser recently sent me a link to his entry in the B’Twin/ Local Motors design competition (see the other entries here). His velomobile, with LED lights integrated into the shell/frame, sounds pretty interesting, so I want to share a few of the image boards here along with Eric’s description of the concept:

“The Petal Velomobile is the beginning of the new iconic brand of ultra-lightweight and aerodynamic vehicles developed around a diverse amount of user preferences and personality types, to usher in a new era of human powered mobility. We have focused on solving our problems with the same toolset for far too long, while electric cars may solve our issues associated with energetic consumption and pollution; ultra-lightweight, affordable, and aerodynamic human powered electric hybrid vehicles provide a solution with a miniscule carbon footprint and unrivaled transit potential that can dramatically reduce healthcare costs associated with a sedentary lifestyle.

As any vehicle serves as a vessel for your personality and self expression, the Petal Velomobile is infinitely customizable to suit your mood and personality, beyond any other product on the market. The stretchy gore-tex membrane easily pops on and off the frame. Because the fairing elements are nonexclusive and variable in vapour resistance, the enclosure can be modified to provide comfort for almost any weather condition. Similar to an iphone case or pair of shoes, the inter-changeability of this fairing allows it to truly become a fashion accessory. Infinitely personalize-able from baby carriers and storage compartments to custom skins and carbon fiber upgrades, the product extends its reach to a diverse clientele.

Critical to safety, led headlamps combined with oled light panels maintain a strong visible presence night and day. The oled light panels function as directional indicators and customizable kinetic light effects. These highly visible elements highlight the creased knee and shoulder lines of the vehicle; expressive of the rider inside. With a leaning suspension, slippery aerodynamic form, and electric acceleration and hill assist package, the petal velomobile extends the possibilities of human powered transit.

The Petal Velomobile is flexible to a varied amount of users, engaging both urban mobility and performance as critical design parameters. Because the most deluxe model is a fraction of the cost of a automobile, this form of mobility becomes accessible to a completely new demographic. Ultimately the goal of this design is to liberate people beyond the current modes of transit, while maintaining the ownership values of car culture, while emulating the efficiency of mass transit.

As a transit architect, every day bicycle and rowing commuter, and regenerative design advocate, my goal with this project is to utilize existing technology to push the boundaries of our sustainable transit potential. With the constraints of population growth and scarcity of energy resources, we must ultimately elevate the performance of human powered transit to the point where it out competes other modes of transit. In my forthcoming book this vehicle is one element in a new infrastructure typology that utilizes existing right-of-way’s to expand our transportation potential as a society.”

Posted

May 21, 2012

Commuter, Concept, Utility / Cargo Bike

James

Tags:

design competition, LED, reader submitted design, velomobile

Comments

31 responses to “Petal Velomobile by Eric Birkhauser”

Bill Gallagher

May 21, 2012

This is fantastic!!!! An absolute winner!

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romu

May 22, 2012

To me it’s far from being the most interesting project in this competition. As such, there is no real difference (except for the child seat of course) with an already existing velomobile: it’s closed (this kind of velomobile always makes me think of the also closed minded, at least closed to the environment and people around), so too warm. The seat is too low to be really usable in city centers, etc.

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1. Eric Birkhauser
  
  May 22, 2012
  
  Thank you for your critique, it is very much appreciated. It is difficult to move away from the current proven architecture of the velomobile, as the combination of aerodynamics and enclosure around the reclined human form are difficult to deviate away from. An outsider to the automotive industry or the architecture field may comment on a new design by saying that it looks like all of the other rounded shapes with four wheels or like any other angular glass box, but it is always the details that sets a innovative design apart from the rest. That is why I have focused in large part on what lies under the skin; the all wheel drive system, the leaning suspension, and the variable driver positioning system to make my design unique. I believe the skin itself, defining the enclosure with a flexible and removable membrane, is an innovative approach to reducing the weight of rigid body panels and allowing the low cost pop on and off skin to become exponentially more customize-able. The variable membrane approach (different materials can be utilized for different seasons) and the non exclusivity of the fairing (the velomobile can be utilized without the fairing on hot days, with just the upper fairing on rainy days, or utilized as a full enclosure on cold days) is enough in my mind as far as a climatic response and ventilation in the design approach. As far as the riding position goes, it was critical to allow the vehicle to be incredibly streamlined in recumbent mode and incredibly visible in urban (upright) mode. This is why the vehicle gains an additional 40 cm between positions. Nonetheless you are of course entitled to your opinion, and I greatly appreciate your thoughts and criticism.
  
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  1. romu
    
    May 23, 2012
    
    Hi Erik, and thanks to have taken the time to answer. I’ve intensively looked at this competition. I’ve been commuting by bike everyday for 4 years in one of the biggest city in France. And for 3 years, I’ve been thinking of such a new vehicle to fill the needs a classical bicycle doesn’t.
    
    Often, I see a guy with a Leiba velomobile and I don’t want to have one. I see your efforts to lead beyond the velomobile as we know it. But as I understand the Btwin requirements, they ask for an urban vehicle. As such, a system intended to ride at maximum 25 km/h, I think we don’t care of the aerodynamics. We care about versatility and visibility (me, rider, I want to see my environment).
    
    I also participate in French forums about bicycles and velomobile, and all vm owners say the same: ventilation is a problem. If I want to be able to go to work without a special suit, I need an opened vehicle, a vm is too closed. And your project, for the polycarbonate glass will be a problem with condensation, look at the Go-One.
    
    My 2 cents, and I’ve just voted for your project 😉
    
    Reply
    1. Eric Birkhauser
      
      May 23, 2012
      
      Cheers thank you for much for you insight and comments. Glad to hear your green commute is a success. Good feedback, indeed my focus was on the creation of a versatile product that is capable of both higher speeds and urban visibility. That being said, you are correct there are quite a few exceptional offerings that have focused completely on the latter. The ability to utilize just the upper fairing as well as the potential to utilize a more porous skin or perforated skin are also other means that I have offered in the category of ventilation. Yes, condensation is an issue, but I believe it can be resolved with proper ventilation techniques and or utilizing a segmented operable bubble.
      
      Again thank you very much for the feedback, I greatly appreciate your vote and vote on other concepts. My best to you.
      
      Reply
  2. Colin
    
    February 14, 2013
    
    This fascinates me more than the actual article. I am trying my best to get my company, “Pearland Velos” off the ground here in Texas. Your expertise and insight are greatly appreciated. May I correspond privately with you?
    
    Reply
    1. Eric Birkhauser
      
      February 14, 2013
      
      Sure, feel free to contact me at ericbirkhauser@gmail.com
      
      Reply
Jos Sluijsmans

May 22, 2012

Great and interesting design. On September 6th, 7th and 8th the 7th International Velomobile Seminar takes place in Dronten, the Netherlands, New developments in velomobile design and engineering will be presented, as well as issues on infrastructure (cycling highways), pr&marketing and social aspects. http://www.velomobileseminar.com
For some nice pictures of velomobiles check out Jan Beeldrijk’s collection on Flickr:
http://www.flickr.com/photos/janbeeldrijk/sets/72157629900664975/

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1. Eric Birkhauser
  
  May 22, 2012
  
  Thank you very much for you compliment and links. I hope to make this conference as it very much pertains to the subject matter of a book that I am currently working on.
  
  Reply
Bubba Nicholson

May 22, 2012

Wow, it’s my Quest velomobile, down to the EL feature! (velomobiel.nl). I use an ecospeed.com-type motor to run the bicycle gears, though, instead of a bionx-type set-up as the gearing is more efficient if noisy. The switchable child-seat is a nice idea. Ymte is reported to have carried three of them in his Quest with a bike trailer, but sans motor. If I only had pistons like that.
Think about carrying the batteries in front of the two front wheel wells as they don’t come flat enough for the bottom. I rigged a nice marine battery switch for my two bats, but do not use a switch with 1 + 2 on it as combining Li batteries on the same circuit disturbs them. It’s great to be able to switch them as needed, and to be able to charge up at J1772 plugs which are free everywhere currently. Ecospeed.com has a superb 1000W motor/controller/and new Lithium Mangnesium (smaller/lighter than my LiFePO4 setup) battery for the Quest. I also use a take apart hinge, but in the back instead of the front.

I do miss a bubble top, though. Eric must remember to make it high enough to contain a bike helmet with a roll bar above it all, too, that the Quest doesn’t have. The hump behind the head in the Quest is too low, I think, although tourkaps with ventilation are available for it, you can’t wear a helmet beneath them comfortably. The Quest has a new carbon fiber skin, too. Spandex may be coming, sometime in the future. I hope to see Eric in the lane next to me real soon.

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1. Bubba Nicholson
  
  May 22, 2012
  
  I forgot, the EL feature is too dim to use as a turn signal. I put a set of wig-wag amber turn signals from Ebay on mine controlled from a motorcycle light switch on my tiller. I hope Eric will do everyone a favor and include bright turn signals and stop lights as making the wiring harness myself has been quite the learning experience–one of those everyone should avoid.
  
  Reply
2. Eric Birkhauser
  
  May 22, 2012
  
  Thank you for your feedback, indeed head and helmet clearances are critical. Specifically how much clearance is preferable for you? Potentially a sliding segmented approach to the bubble would allow for more flexibility and ‘openness’ based on user preferences.
  
  I have had a lot of feedback on collisions and impacts. This is where the design blurs between car and bicycle, in that I am uncertain about the implications of roll bars and safety cages while maintaining an extremely lightweight design. Great food for thought as the design progresses.
  
  Wow, those ecospeed kits are nice. For this design I went with a much smaller 250 Watt motor, which keeps this design ‘trail’ legal. But it would be quite exhilarating to have a big battery bank and 1000 Watt motor!
  
  Thank you for your informative thoughts, please keep them coming.
  
  Reply
  1. Bubba Nicholson
    
    May 22, 2012
    
    Collisions and impacts on the nose are most likely, as demonstrated by the numerous “crash” photos on the internet. About 20% of velomobiles suffer some sort of frontal damage and the first few weeks of ownership are the most dangerous.
    I utilize a special toroidal bumper on the nose of my Quest that is designed to mitigate frontal impacts. I mount a light inside it to minimize holes in the carbon fiber body skin at that critical point.
    The ecospeed set up, even with the 1000W motor are perfectly legal bicycles here in the USA. Other countries allow only smaller motors. I have a 500W motor now and with the added weight of my batteries, I drag race dump trucks and lose to them. I’m looking forward to upgrading to a 1000 W ecospeed motor for better acceleration and higher top speed at around 45-50 mph.
    
    Reply
    1. Eric Birkhauser
      
      May 22, 2012
      
      Very cool, do you have any speeding tickets yet? 🙂
      
      Reply
Ben Seibel

May 22, 2012

The design is stunning with two missing ingredients: TTW suspension and ventilation. TTW, tilting three wheel, because you have to be able to lean into turns. Ventilation because it gets hot when you are pushing on those pedals. The ventilation problem is like TT helmets. They want to be aerodynamically slick but without ventilation they become hot boxes.

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1. Eric Birkhauser
  
  May 22, 2012
  
  Hi Ben,
  
  Thank you for your thoughts, very much appreciated. The design is a tilting three wheel suspension, my apologies for not being clear about that in the drawings. I agree not being able to lean into corners and maintain the bicycle experience would be unfortunate. The bottom fairing is V shaped like a boat hull to accommodate this motion. The battery bank sits at the bottom of this ‘hull’ to allow for the best weight distribution possible.
  
  Yes ventilation is absolutely critical, that is why the fairings are not exclusive and the porosity of the skin itself is variable (by changing the skin). I noted this issue in an earlier response above. You are absolutely right, the human body generates a lot of heat whilst in motion, and we do not want to cook and velomobilists! Another component of the design to note is the large wheel openings which permit the vehicle to turn, lean, and alternate between upright and recumbent positions. These openings will allow for a significant amount of ventilation, but a much more refined CFD analysis will be necessary to optimize the fairing design.
  
  Ben thank you for your feedback, very much appreciated.
  
  Reply
  1. art
    
    May 22, 2012
    
    One of the most important things you can do to keep the inside of this cool is minimizing the area of the head bubble. Sitting under one of those things on a sunny day with anything less than hurricane force ventilation is like being a bug under a magnifying glass. The large wheel openings will keep the interior cool at speed, but if you ride this in the rain as designed you’ll get blasted in the face with road spray every time you lean into a corner. Even with some complicated fenders there’s still going to be a lot of water splashing around inside the fairing. Personally, I would kick the front wheels to the outside of the fairing and add an inlet vent on the floor and outlet vents just behind the shoulders.
    
    Reply
    1. Eric Birkhauser
      
      May 22, 2012
      
      Art,
      
      Thank you for much for your thoughts and insight. You couldn’t be more right about reducing the size of the bubble as a means of reducing the velomobile solar oven effect. The size of the bubble in this design was informed by the solar gain as you mentioned and the visibility and perceived openness. Shown more strongly in some rendering than others, the intent is to have a reflective coating to reduce this gain as well.
      
      Great comment on the splashing issue, you may be right about pushing those wheels out. The fenders cover half of the wheel, but you are more than likely correct, it will not create 100 percent protection. My goal was to reduce drag by sucking the wheels into the fairing, but the size of the openings, to accommodate for the leaning suspension, is large enough to reduce in any loss in drag. So upon further examination your critique will very much inform the future design. Certainly the approach of pushing the wheels outside of the fairing is a proven one, as the Birk Butterfly is one of the most beautiful human powered vehicles ever made.
      
      Art thanks for your comments, I look forward to more in the future.
      
      Reply
      1. art
        
        May 23, 2012
        
        I did this both ways back when I was on a university team competing in the ASME HPV race. Putting the wheels outside exposes them to the air, but the trade off is less weight and frontal area for the fairing. It will also give you more space to widen or narrow the front track to tune the handling.
        
        Reply
        
        Eric Birkhauser
        
        May 24, 2012
        
        Thank you for the insight, indeed a good trade off. I will explore pushing the wheels outside of the fairing for the 2.0 version. Again thank you for your time and willingness to share your expertise. My best.
gran torino

May 22, 2012

Hello, l have partecipate too, to this challenge. How bizare to see only your project here.
Now some critics.
How do you get-in if you could not touch the road under your feets?
You jump in? How about the equilibre when jump?
How does the passanger get-in?
Is easy to speak about “The stretchy gore-tex membrane” but where is your frame?
Your transmission system on both two positions?
What about storage spaces?
Thats all. For today

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1. Bubba Nicholson
  
  May 22, 2012
  
  As I actually have one, I can answer your questions. There are only about 12 Quest velomobiles in North America right now. To enter mine, you stand next to it, put a leg in, sit on the top, and slide down inside. There are oval holes under the petals for reverse. You set the parking brake before “jumping in”.
  I live in Florida, the weather is very hot during the summer time. I have a head out Quest and foot holes beneath, so ventilation is no problem at all, plus it’s electric most of the time.
  The Quest uses a 27 speed Shimano set up with Sram grip shifters, thumbies would be better. No water gets inside the fairing. Rain is no problem velomobiel.nl provides a head out cockpit cover. Keeping the wheels inside the body provides 10% higher speeds than open wheel wells (Quest vs. Mango velomobiles). The Carbon Quest is the fastest european velomobile. The Australian Avatar, which looks like this design, is reputed to be faster.
  
  Reply
2. Eric Birkhauser
  
  May 22, 2012
  
  Bubba,
  
  Your follow up is very much appreciated. I can add maybe a few more things to clarify the concept further. The ‘components’ drawing shows the fairing in its open position, the upper fairing pivots on a hinge a full 90 degrees to allow access to all components of the cockpit. The leaning suspension will have a lockout for parking mode. To sit, one simply steps across the bottom fairing to straddle it, and then simply sits down. While seated, with the fairing open, one can easily place both feet on the ground on opposite sides of the vehicle, which will just as easily allow someone to stand up again and exit the vehicle.
  
  Sure, I can understand that the fairing frame is hard to make out in the renderings as the skin is not transparent; to clarify, it is located at the perimeters of the openings as well as the creased knee lines of the upper fairing and creased bottom v line of the bottom fairing. It can be seen in the components drawing with the fairing open. the top and bottom fairing are supported at the three same points, in the front off of a tube cantilevered from the bottom bracket, and to the rear in two locations on either side of the seat.
  
  In the ‘practical’ drawing the vehicle is shown in both recumbent and upright mode. The twin tubes of the main frame are pinned to allow for this pivoting movement, while maintaining the fixed angle of the seat tube and front suspension. An adjustable air shock would allow for a transition from upright to recumbent mode with a push of a button, while the inverse transition would necessitate a manual adjustment. this drawing also shows two options for cargo behind the seat, one being a plastic or carbon fiber container mounted to the back of the seat, the other being the most precious cargo alternative; the child seat.
  
  Gran Torino, thank you very much for your questions, I look forward to more tomorrow, they are very much appreciated.
  
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Nick F

May 23, 2012

The funniest part about this competition is one requirement from the design brief:

“Price – less than $2000 USD”</b

Hahahaha….. right. There isn’t a velomobile on the market for that, let alone the wacky concepts being entered. They’d be lucky to cost less than $10 -20K.

The competition founders are correct, of course, and the entrants just aren’t getting it… developing a velomobile to be low priced is absolutely the biggest obstacle to their mass adoption. This particular entry is nifty, but look around the net, and you’ll find at least half a dozen equally beautiful velomibles in production that you’ve probably never heard of. They rarely sell – because they cost more than most used cars (and some new ones…).

That being said, I love velomobiles and wish it would be practical to own one. This competition is just a slightly vain attempt at solving the lesser aspects of a problem. Given that the competition sponsor is actually a bike manufacturer, it’s a major disappointment that they didn’t step up and raise the stakes by actually picking the top 3 feasible candidates, prototyping them, and then choosing a winner. That wouldn’t have been more expensive than the $15K they promised as prize money – particularly if they even attempt at judging based on their requested $2k price point.

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1. Eric Birkhauser
  
  May 23, 2012
  
  Nick,
  
  Thank you for your thoughts, yes indeed, price is the stiffest design parameter in this competition. Some electric kits far exceed that price alone. However, I think it would be possible to make a stripped down version of this concept, with entry level components, and the frame, seat, drive-train, suspension, and wheel-set for around 1.5 K. My hope is that with mass production of the cnc bent fairing tube frame, complete with latches and hinges, could be produced for around five hundred dollars. It could then be possible then to utilize an inexpensive fabric to create the enclosure for around two hundred dollars. So I think it is possible to sell a base model in the 2K price range. However, adding OLED and LED lights and the polycarbonate bubble would then be more than likely an additional .5 to 1K investment. And when you seek to electrify the concept you will more than likely add another 1 to 3K to your investment. So it is feasible to have a base model for 2K, but a deluxe electrified concept, as shown in the renderings would more than likely approach the 4 to 5K range, which is on the lower end of the velomobile pricing spectrum. An on another note, I agree, there are many stunning velomobiles in production, but I think there is room for a few more…
  
  My hope is that the advantages of purchasing a velomobile such as this over a cheap car will make it attractive to this new non car oriented generation. If the velomobile can truly become an attractive and safe mode of transit, then I believe with financing or zipcar type programs this product could become much more successful than it currently is. There are two enormous obstacles in this challenge; marketing and infrastructure. In the US, most people have no idea what a velomobile is, let alone the performance advantages of the recumbent position and a fairing. So great measures will have to be taking to increase the awareness of this new mode of transit. Great caution must be taken to not give velomobiling a black eye while it is in its infancy. Infrastructure, I believe, is the largest obstacle for the velomobile. As an everyday HPT commuter, I am challenged everyday with the limited or nonexistent bicycle facilities in the DC area, and it was recently ranked the 4th best American city for cycling. Similar to necessity of track for rail transit, an infrastructure of dedicated high speed bicycle facilities that are successfully separated from pedestrians and automobiles is absolutely essential. To truly capture the high speed potential of the velomobile, whilst maintaining the highest level of safety, this type of infrastructure is absolutely critical. This will be an enormous and extremely expensive challenge, but the these costs are miniscule when considering expanding automoble, bus, light or heavy rail transit systems (let alone the cost savings for health care). This is a very complex issue that deserves great study, which is why it is the subject matter of a book that I am currently working on.
  
  So yes, Nick, the cost is one issue, one which I believe can be resolved, but there are many more obstacles on the road to success for the velomobile. Thank you very much for you insight and valid points on the matter, my best.
  
  Reply
Eric Birkhauser

September 18, 2012

For more on this project and other related projects, go to http://birkhauserdesign.com/ , thanks!

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Daniel Peper

November 7, 2012

Hello Eric,
A beautiful design, without a doubt. Have you considered designing the shell so that it would fit tricycles that currently are on the market? i hope you have, or would consider it.
My brother and I ride ICE Adventure 2fs trikes. We ride them every chance we get. I would be very interested in buying an affordably priced shell to enclose our trikes, both for aerodynamic benefit, and to allow driving in cold weather.
IMHO, including leaning wheel steering is your prototype is a feature that would increase the complexity of the design, enough to cancel out any benefit from tilting. Many velomobile riders are able to pilot their velos through corners at high speed without wheel tilting capability. From my experience in riding my trike, most of my route is straight forward where precise high speed steering would never come into play.
The shell should be very lightweight, in order the velonaut to climb hills. Your design with the use of fabric seems excellent in this regard.
I am retired, so I have the time to help developing a frame with fabric cover for my trike, if you could use a hand.
Thanks,
Daniel, from Plymouth, Michigan, 48170, USA

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Eric Birkhauser

November 7, 2012

Daniel,

Thank you for the feedback, I agree the tilting mechanism creates an array of issues that would dramatically increase cost and complexity. On that note, Arnold at Raptobike has seemed to have perfected a cost effective tilting mechanism, in a delta configuration, https://www.youtube.com/watch?v=GEOGr3oy3H4 . Seems like it should be a breakthrough design.

I would be interested in discussing the membrane fairing more in detail, please feel free to contact me at ericbirkhauser@gmail.com

Thanks,
Eric

Thanks!

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Howard

December 11, 2012

IMO the tilt feature should be optional. Very optional. Especially with price being a design consideration. A TTW has all the “disadvantages” of a bike and none of the advantages of a trike. Especially in urban mode. Sidewinds acting on that much fairing will make for a very unstable vehicle. I’m not that metric but 50cm sounds optimistic for a practical vehicle track. I just Googled a conversion… 50cm is 19.7in…!!! … 28in (71cm) is a very narrow track, suitable only for a racing recumbent trike and in the U.S. more than 32in (81.3cm) becomes problematic with doorways. Even for a TTW a track of 24in (61cm) is more realistic than 50cm.

IMO the electric assist should also be optional. Especially with price being a design consideration. The aerodynamics of the Quest are so superb that electric assist becomes more trouble than it is worth for the majority of units in operation. The weight of the composite body makes hills a challenge to SOME and this is why electric assist must be offered as an option. One of the earlier reviewers said the seat wasn’t high enough. I disagree. Situated over the rear wheel as it is, the seat cannot be lower than ~24in. if 20″ wheels are being used. That is too high for a non-tilting design. Trust me, the average velomobile buyer does not want to work as hard as to have to balance a TTW as they would a bicycle. I agree with the idea of using the more or less “standard” design of tadpole recumbent trikes to start with. The concepts of lightweight bodywork are worthy in and of themselves to not require re-inventing the wheel with respect to the chassis.

Finally, there will never be a completely separate, but equal, road system for HPV traffic in the U.S. It just isn’t going to happen. Advocacy for HPV traffic must be developed to “train” motorists to respect HPV traffic. This is being done in Portland, OR to good effect. When HPV traffic can use the roads as they are without requireing separate and expensive infrastructure for their exclusive use there will be less initial resistance to purchasing vehicles like the Petal.

H

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Christophe

January 31, 2013

The Velomobile seems very unstable, not rigid enough and sensitive to wind.
But the pictures are beautiful. A beautiful image represents 50% of success.

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Mark

May 13, 2014

Eric,

Any update with your design in the states? I have some ideas, I would live to share with you.

Reply