The Emcycle: a 3-wheel, tilting, fully-enclosed 500 W pedelec weighing just 80 lb (36 kg)
By Mike Hanlon
February 28, 2012
The potential for electric assisted human powered vehicles to play a substantial role in the transport systems of the future is immense, and there has never been a better example of this potential than the Emcycle concept. The Emcycle is a tilting, three-wheeled pedelec (electric pedal assist), with a foam-reinforced, Tegris composite monocoque body, full suspension and a kerb weight of just 36 kg (80 lbs).
The Emcycle will initially offer 500 W of electric assist with plans for 1,000 W (1 kW) and greater versions later. Indeed, there's every reason the Emcycle would make an ideal basis for a full electric version without pedals - as you will see later, a modest 2 kW motor combined with the Emcycle's light weight offers a very frugal yet rapid commuter vehicle.
Car-like amenityThe biggest selling feature of the Emcycle is obviously that it is an electric bicycle with nearly all of the comfort, safety and weather protection of car.
The Emcycle also offers many of the most important creature comforts of a car, such as instrumentation, wipers, an entertainment system and a huge lockable carrying capacity.
In addition to its own weight, the Emcycle can safely carry an additional 320 pounds (144 kg), including the weight of the rider, making it ideal for the city bike rental and inner urban delivery vehicle markets.
It is as a commuter vehicle that the Emcycle has the most potential though. It can ride on the bike path, it can mix safely with traffic, and the amount of energy it uses when being replenished may well be insignificant on your electricity bill.
The Emcycle is the result of many years of design experience in many different industries - Emcycle's creator, Michael Scholey has designed automobiles for British Leyland, toys for Mattel, been Director of R&D; for a range of personal safety products such as respirators and hearing protection ... plus many more projects of different kinds in his role at a consulting industrial design company.
His work has taken him into many different technical fields, and for a period he worked at an industrial fabric company as the technical expert dealing with the aerospace companies such as Lockheed, Boeing and Raytheon.
He even spent time designing an electric car for one of the many start-ups in the growing EV space.
The Emcycle is "partially a product of many years of thinking about transportation systems of the future," says Scholey, who undertook post-grad transportation studies at the Art Center College of Design in Los Angeles, "plus a fascination with new materials and improved ways of doing things."
The purpose of this vehicle is to enable anyone to commute in a degree of comfort and with more safety than on a normal bicycle", says Scholey.
"It is not a substitute for a sporting cycle but more of a substitute for a car," he emphasizes. "To that end it has the size and economics of a bicycle with the amenities of a car."
"The electrical assistance and full body enable a rider to ride in their normal clothes vs spandex and arrive ready for work or play vs all sweaty or soaked and worn out, and because it is enclosed, no helmet is required to be worn."
"It has suspension both front and rear and the two front wheels tilt to allow bicycle-like banking in corners.
"The bankability is made so that the vehicle stays upright when standing until the rider decides to bank over. No feet need ever touch the wet or dirty street. The two front wheels also give more secure cornering traction and superior braking performance, and with three hydraulic disc brakes, it stops rapidly and safely. It also has a handbrake for parking.
Access to the bicycle lane with an enclosed bike will be a novelty, particularly one which will power along comfortably at 25 km/h (15 mph) - a speed not achievable on a human-powered bike without some exertion.
Using the bicycle lane whenever possible, the Emcycle is hence very safe. On the roads, a disproportionate number of fatalities occur when vulnerable road users (bicycles and motorcycles) mix with less vulnerable (cars). In this regard, the Emcycle is likely to fare better than either the bicycle or the motorcycle in a crash with a car. That's just opinion at this stage, though in discussions with Emcycle's designer, he did mention that he thought the Emcycle would perform very well in certain tests and not so well in others.
Side impacts will obviously be one of the challenges of the Emcycle in terms of being able to match car crash test standards, but it must be remembered that the Emcycle is significantly safer in its intended environment, and much safer than a naked bicycle when forced to mix with cars.
In my experience, the direct routes offered by bicycle paths often make commuting by bicycle much faster than a car in inner urban environments. Bicycle paths usually go straight through parks, whereas cars usually get to go the long way. Bikes almost always have privileged access lanes which bypass major traffic lights and other time-wasters, and the bicycle path never gets as congested as the road.
Hence the Emcycle offers a genuine alternative for commuters.
The use of Tegris compositeThe key to the Emcycle's remarkable weight and strength is its polypropylene thermoplastic composite Tegris monocoque chassis.
Tegris is quickly gaining a reputation as being better than carbon fiber composite for many applications, along with offering irreplaceable material qualities to many new industries. It's no accident. Milliken is one of those companies that makes lots of things you use, but they're part of other products, and hence not branded.
Milliken set out specifically to engineer a composite with lightness, stiffness and excellent impact resistance, at the request of the United States military. Its impact resistance is so good in comparison to typical thermoplastic and thermoplastics composites, that it is being used in protective clothing against fragment, projectile or blast threats, and in body armor against ballistic threats.
The first product to be made entirely of Tegris is the Ultimate 12 Tegris kayak from Native watercraft - you'll note that the product page specifically states: "Hammer strikes won't harm this hull, so it can shrug off hard landings and rocky bottoms like nobody's business. And yet with all that strength, the Ultimate Tegris tips the scales at just 36 pounds (16 kg)."
Tegris is also the key ingredient in Panoz's REAMS (Recyclable Energy Absorbing Matrix System) composite, which is used in making stronger and lighter racing automobiles.
The Monocoque Chassis
Monocoque is a term that normally doesn't get applied to vehicles as small as the Emcycle but it essentially means the construction uses an object's external skin as the load-bearing structure, as opposed to using an internal frame. Planes pioneered the idea a century ago but it wasn't until the 1958 Lotus Elite road car that we saw a monocoque chassis in a production road car.
The splash caused by the Elite's monocoque chassis was nothing however, compared to the reaction to the Lotus 25 Formula One car designed by Colin Chapman for the 1962 season and rolled out for the first time at the Dutch Grand Prix.
The car won three races during the year and comprehensively proved that a monocoque chassis could be both lighter and stronger, and at the same time provide a safer car for the driver.
Quite soon, all the cars on the grid were using monocoque chassis, with the first carbon fiber monocoque appearing on John Barnard's 1981 McLaren MP4/1. Now, all Formula One cars use carbon fiber composite monocoques, and racing is a safer place for it.
An example of just how safe a carbon fiber composite F1 car is these days was Giancarlo Fisichella's crash at Silverstone in the 1997 British Grand Prix. Fisichella's Jordan plowed into the barrier at 227 km/h, decelerating to zero in 0.72 seconds according to the black box. He suffered a minor injury to his knee.
So the Emcycle is not just light, but also strong, and the resultant 80 lb (36 kg) kerb weight bears testimony to the benefits of this type of construction.
Further enhancing the strength of the Emcycle's chassis is the use of foam for reinforcement, an area of composite construction that Emcycle's Michael Scholey has been experimenting with for years.
Sadly, the polycarbonate dome that sits atop the Emcycle is not nearly as bullet-proof, otherwise the Emcycle might have claimed the title of the world's cheapest armored vehicle.
The screen might offer full 360-degree visibility, but I have my doubts as to whether the design could be used anywhere but in cold climates - a bit of sun on the Emcycle might well turn it into a mobile sauna.
Horsepower, Watts, Humanpower and electric-hpv hybridsJust as petrol-electric hybrid vehicles get their motive power from two sources (petrol via the internal combustion engine, and batteries), the Emcycle is a human-electric hybrid drawing its energy from two sources - its batteries and the human riding it.
Nominally, for insurance purposes, the first Emcycle will have a 500 W motor, which can be used in conjunction with the power supplied by the human riding it. This enables it to meet future EU regulations and require no license or insurance.
Now 500 watt equals 0.67 horsepower, and the term horsepower derives from exactly that - the power output of one horse. Way back at the beginning of the industrial age, Scottish inventor James Watt invented a new and more efficient steam engine, then was faced with selling something brand new - a machine that could perform work.
Having no precedent upon which to base his business model, he made the sound judgement of selling his machines for a share of the money they saved in comparison to traditional methods.
The first round of sales for his revolutionary steam engine were to people who already owned and knew the value of the older and less efficient Newcomen steam engines - the mines - and he cleverly continued to take royalties for the amount of coal saved by replacing a Newcomen with one of his.
When he moved into the next phase of marketing his engines, the customers were mill owners who were actually replacing horses with the steam engines.
So Watt set about determining a measure for the amount of work a horse could perform for comparison purposes, and the mill gave him a perfect context. From observation, he determined that the average mill horse could turn a mill wheel 144 times in an hour, pulling with 180 pounds (81 kg) of force on a wheel that was 12 feet (3.6 m) in radius. He rounded out the calculation to 33,000 foot-pounds per minute in 1782 and horsepower began its journey into becoming the first widely recognized unit of power.
Watt himself would later have the now accepted International System of Units (SI) power metric named after him, with 745.7 watts equaling one of his original horsepower.
The interesting part of the story is that Watt used the work output of his machines, as measured by the number of horses they replaced, to both demonstrate the value of his machinery, and to cleverly monetize the invention.
To some extent, the model is still alive today, with automotive manufacturers offering more powerful engines in the same car at a considerable premium.
How much power can a human being produce?The biggest difficulty in comparing the output of an animal and a machine, is that engines don't tire, while horses and humans tire quickly. Humans and horses can both produce prodigious horsepower in short bursts, but this drops away rapidly.
Once upon a time, we'd have struggled to address this issue accurately, but the invention of the cycle power meter has changed all that. Now we can accurately visualize the levels of horsepower that human beings can sustain over time.
Tour de France enthusiasts already know from the telecasts of the great race (which now feature live transmission of data to on-screen information graphics), that elite level Tour de France cyclists put out around 250 watts when they are aerodynamically shielded by the field, to more than 500 watts when they are attacking on hill climbs. It should be remembered that Tour de France riders are the very elite of world cycling, and not representative of the average human being.
Cycling Power Models put the above chart together, which I think gives a clear picture of how much a healthy human can play a role as a power source over a one hour journey - about 200 W for a healthy amateur cyclist, through to over 450 W for elite cyclists.
For the sake of easy calculation and comparison with other hybrids, I'm going to call the average human input 500 watts - partly because many of the electric motor power output figures quoted in hybrid cars are peak power figures and partly because most manufacturers fudge the figures just a tad anyway.
Putting the weight of the Emcycle in perspectiveThe biggest enemy of performance and/or efficiency in any form of motorized conveyance, from a racing car to an ecomarathon special, is weight.
This makes the Emcycle unique, because it is so light, that it almost defies comparison with conventional forms of transport.
The lightest cars currently on the international market are two-seater city cars such as the 900 kg (1,984 lb) Mitsubishi i, the 1,090 kg (2,043 lb) Volkswagen up!, 860 kg (1,896 lb) Toyota iQ (below image, top left) and 730 kg (1,609 lb) smart fortwo (ED electric drive model shown in below image at bottom left) - all of them morbidly obese by comparison to the Emcycle's 36 kg (80 lb).
If the Volkswagen up! (below top right) weighs nearly 30 times as much as the Emcycle, it will obviously require 30 times more power to achieve similar performance levels, and 30 times more work to achieve the same result.
Premium green cars such as the Toyota Prius (1,380 kg/3,042 lb - above image bottom right) and Honda Civic Hybrid (1,250 kg/2,756 lb) can have all the aerodynamic tweaking you like, and they're never going to achieve the frugal energy usage of a vehicle that weighs just one fortieth of the mass, and has a frontal area of one third.
Toyota claims a drag co-efficient of 0.25 for the Prius, though tests suggest it is actually closer to 0.30. The drag co-efficient is very important to a car's efficiency - equally as important as frontal area. How much power you need for any given level of performance is directly proportional to both. We don't know the drag co-efficient of the Emcycle, but as the frontal area of the Emcycle is much smaller than a car's (I estimate one third the frontal area), further significant efficiency gains are likely.
My vote for the best pound-for-pound commuter vehicle in the world right now would probably go to Honda's PCX 125 scooter. Its 11.1 bhp engine is powerful and flexible and sweet to ride, yet it uses miniscule amounts of fuel thanks to an advanced fuel injection system. It delivers 110 mpg (2.1 L/100 km) because its motor only needs to push around a kerb weight of 127 kg (280 lb) - yet it weighs more than three times as much as the Emcycle.
A Bergman 125 maxi scooter from Suzuki, another two wheeler with a great deal of creature comforts, comes in a lot heavier at 159 kg (350 lb) dry (no petrol or oil), while heavier commuters such as the Piaggio MP3 (208 kg/458 lb) dry), 650 Bergman maxiscooter (269 kg/593 lb dry) are respectively six and eight times heavier.
So even in comparison to the humble scooter, the Emcycle is considerably lighter and hence has a big advantage in terms of efficiency.
The final bit that you need to experience to understand is the compatibility of human and electric power - when you want to go a little bit faster, the extra 500 watts you can summon can propel the bike forward so quickly that you feel superhuman.
Cars only use full power under acceleration - cruising along and maintaining a particular speed does not require much power at all - hence the Emcycle produces all its power when it is needed, and thanks to its low weight, it uses cents worth of power, not dollars worth of gasoline.
So given that the maximum human thrust available for the first few seconds from standstill well exceeds 500 W, the Emcycle has a 500 + 500 = 1,000 watt output and courtesy of its feather-light weight, it has a very respectable power to weight ratio.
Comparing this with the aforementioned vehicles and their power outputs offered some interesting insights into the nature of the Emcycle due to its light weight.
The Emcycle is so light that the 500 W electric assist will offer pretty quick acceleration - you will still need to pedal a bit, but not very much, as the emphasis of the Emcycle is to enable people to wear normal clothes and not to need to exert themselves.
Ten years ago, Gizmag's entire editorial team spent two weeks with Aprilia's Enjoy - might I suggest you read the article in conjunction with this one - we loved the Enjoy, which was essentially a 29 kg (64 lb) bicycle with 200 W of pedal assist and a top speed of 27 km/h (17 mph).
The Emcycle weighs just 7 kg (15 lb) more than the Enjoy, has a minimum 500 W of pedal assist, and the first version of the Emcycle to be made will have a 500 W motor and a limited top speed of 25 km/h (15 mph). Hence if we were more than happy with the Aprilia's 200 W, I expect the Emcycle will be very brisk.
Part of the secret of putting the miniscule amounts of energy the machine uses to most advantage is in the compatibility of human and electric power - electric motors make maximum torque at zero RPM, so they are great for getting you going from a standstill,
Simply put some grunt into that first push and a pedelec accelerates rapidly, "like some giant hand is pushing the bike from behind." This single aspect takes a huge amount of effort out of riding the bike.
It also makes a lot of sense in personal transportation to have a vehicle which isn't range sensitive - the thought of being left stranded with an empty battery rates for most people somewhere on the fear scale between a trip to the dentist and public speaking.
As the Emcycle is perfectly usable without electric assist, becoming in effect a heavy bicycle, it can be safely used until the batteries are exhausted, and you'll still get home with minimum fuss.
In conclusionThe Emcycle seems to have all the boxes ticked as far as a future participant in the personal transportation arena - Scholey has something viable that appears to challenge conventional transport solutions and achieve a level of energy efficiency that cars will never get even close to.
It's still a concept, and Scholey is seeking investors in the project to ready it for manufacturing.