Human powered helicopter

 

It was great to hear that the Sikorsky challenge has finally been conquered. This challenge was put forward by the Sikorsky Aircraft Corporation way back in 1980 offering half a million smackers to anyone who could create a human only powered craft that would hover stationary in a space of no more than 30 feet x 30 feet for a minimum of 60 seconds at an altitude of at least 10 feet. Anyone who knows something about air flight will tell you that this a huge challenge, pushing the absolute boundaries of what is considered possible.

But, in July a Canadian team (Aerovelo) at the University of Toronto comprised of students, staff, volunteers and professionals claimed the prize with their human powered copter called “Atlas”.

The amount of engineering and trial and error that went into designing and building the ‘copter is daunting. Here are some impressive specs of the machine:

Rotor Radius: 10.2m (33.5ft)
Maximum Dimension: 46.4m (154ft)
Height: 3.7m (12.1ft)
Overall Weight: 55Kg (121.4lb)

Can you imagine what it takes to spin up a four 33 foot blades and lift yourself plus the 120 pound machine into the air, at the same time controlling the flight in three dimensions? WOW is all I can say!

Atlas ready for the winning flight

When you see the entire copter sitting there on the ground, you can really appreciate the engineering that went into making such a huge machine only weighing 120 pounds. The framework is made of composite rods and wire, so it is lightweight and just strong enough for the task at hand. The team went through many design changes over a year as they worked out the limits of the framework, snapping tubes and breaking many support wires along the way.

The Atlas transmission system

Everything about this craft is cool! Here is a shot of the transmission system which includes a high RPM fixed gear rear wheel that acts as a dampening system to smooth out the pilot’s pedaling efforts. This makes sense because there is little power at top dead center during a crank revolution that would lead to slowing of the rotors and would probably cause huge oscillations in the frame and massive power loss. This flywheel keeps the power output constant without really storing any energy and that would break the rules of the contest. On the left side of the crank, there is a set of pulleys and guide idlers that transfer power via cable to the rotors. Cable drive is necessary because a chain of that length would weigh too much. Check out the huge chainring; there must be 80 teeth on the beast!

The cockpit?

The pilot sits atop a carbon fibre road bike frame that is suspended in the main frame by wires. Craft control is accomplished by rods attached to what used to be the brake levers. I have not seen much detail on the control system, but would I imagine that it works by simply flexing the frame so that the pilot can change the angle of the rotors slightly to fine tune position while in flight. According to the rules, they have to stay within a 30 foot by 30 foot space for one minute.

One of the rotor flywheels

Every part of the craft is made using the lightest possible materials. This required some seriously detailed work from the team. The picture above is one of the four rotors, a huge spoked wheel made of composite materials and wire for spokes. If you think that lacing a 36 hole bicycle rim is a chore, just imagine making this wheel!

So, a big AtomicZombie congrats to Team Aerovelo for rising to the challenge and pressing forward after many broken frames, snapped wires and crash test flights! A lot more info on Team Aerovelo's Atlas craft can be found on their website here: www.aerovelo.com

~ Brad

A unique highway lowracer

A big wheel forkless lowracer

Even though my bike building has come to a bit of a halt this year, that doesn't mean I’m not coming up with new ideas on a daily basis.  A few times a day, I like to find a quiet place to relax with a notebook and sketch up new project ideas. I have really missed my Marauder. I think it may be time to make another long wheelbase lowracer so I can get out once in awhile to feel that burn as I push both machine and engine to the limits. The terrain out here is not the same as the city, so my lowracer will need to have suspension to take me down the gravel road out to the highway. There isn't much traffic on the paved highway around here and the ride would certainly be challenging thanks to hills and tight corners.

Another option is to transport it to a nice stretch of country road about 15 minutes from here where there is very little traffic and fairly smooth straight terrain. There are many cyclists using this stretch. I can just see myself eating roadies up once again as I slip under the wind and pass them one by one!

Some forkless bike examples

This time though, I want a very unique lowracer that has 700cc or 26 inch wheels on the front and back, a rear suspension, over seat steering, and no front forks. Yep, you read that right, no front forks! I have two designs for a forkless bike: one with a hinged triangle and the other with a wrap around frame that allows the front wheel to pivot much like the front wheels of a quad or tadpole trike.

Having no fork over the front wheel would mean that a larger wheel could be used without obstructing the pilot’s view. This will also smooth out the ride, so it would be a decent chassis for an aerodynamic fairing, allowing the rear suspension and long frame take up the bumps. Suspension is a must on a faired lowracer since these things can easily reach automobile speeds, making the smallest bump feel like a pothole. The forkless design and long wheelbase configuration also keep the front of the fairing low so that you can see the road ahead rather than having to peer around the body. This type of streamliner would not be all that great for pack racing on a track, but out on the open road, it would be a real blast!

A crazy pivot fork bike

The easiest forkless design is shown in my sketch and in these cool examples, where the hub pivots on a kingpin held in place by a single tube that wraps around the wheel, leaving space for the turn. I would run a connecting rod up to a control arm just behind the front wheel and then use dual cable steering to get around the curved tube so that there would be less flex in the system and tighter side tolerances for a fitting into a full fairing.

My other version involves a hinged triangle with the pivot very low behind the wheel to keep the tiller effect minimal. I have tried this in the past on this crazy ride called "Tour De Hell", but the result was a bike that had serious bad attitude and took a lot of practice to ride smoothly.

Of course, having a short wheelbase and a huge amount of tiller, this bike steered like a front end loader, swinging from side to side and causing serious steering feedback. I think this system would work out on a long wheelbase recumbent if the pivot had more caster and was placed much lower to get it closer to the axle. I am not sure if I will actually try the pivot fork design since the other method would defiantly work as expected.

Perhaps this winter I may cut some tubing and lay out my new forkless highway lowracer. I always wanted to build a long wheelbase lowracer and then go all the way on a fiberglass fairing so I can get out and push the limits of what is considered possible under human power. I certainly won't be heading to Battle Mountain to race with the big boys of speed, but I would certainly have fun smoking past road bikes doing 50 MPH on a faired lowracer down our country roads!

~ Brad

No summer this year!

More rain - what a surprise!

Well, it's official - this has now been the worst summer I have ever experienced in all my time on this planet! I have a total of five days of bike building time in since the snow melted and will be officially throwing in the towel this year. Normally, I can get three to five bikes out in a year, but this year will leave us with only one new bike plan, the Transporter Cargo Bike. Now, it may sound like I am giving up too soon, but with the fact that it rains almost 90% of the time here lately and the fact that I have oodles of yard work to get done mixed in there with a 10 hour work day, it's not lookin' too good, eh.

There have been some cool lightning storms this year which is pretty typical, but the rest of the time has been spitting rain every hour or so. I would rather have a massive downpour for hours and then some clear skies for a few days, but this year it has ALWAYS, ALWYAYS, ALWAYS been raining just a little. This makes it like a swamp down the hill in front of my bike building shack, and since I have to work and photograph projects outdoors, it is impossible. It's just enough rain to stop me. And, I have given up falling for that stupid "20% chance of rain" lie they tell on the weather network because what that really means is spitting rain every three hours so you can't work outside, Suckah!, bwa ha ha ha ha!

The line snapper after a good wind

Another thing that is happening around here is intense bursts of wind. Now, I'm not talking about a nice summer breeze, I mean tree-snapping, furniture-flinging, tent-collapsing wind. This unnatural weather amplification downed this old +80 foot tall tree at the corner of our yard and it snapped the hydro line with such force that it broke a hydro pole in half down at the bottom of the hill. The good news is that I wanted to clean up this part of the yard and we now have a woodstove, so free firewood!

Being a noob at cutting wood, I took my brand new chainsaw and worked on this monster tree for three days, getting what seems to be at least a cord of wood out of it. But after a week of use my chain seems dull. Is this normal for a chainsaw? Hmmm...at that rate I might as well look for a huge bow saw and spare the hassle of fiddling around with mixing oil, bar oil, dull blades and all that noise.

This will be my view for the rest of the year

So, instead of fooling myself into believing that I may actually get to build anything this year, I have decided to work on adding some useful stuff to the AZ site. We will be starting the new welding, grinding, and bike hacking tutorials /DVD production soon and I am dedicated to adding all kinds of bike tech calculators to the main site. I want to hear from our community and get a list of suggestions for making online calculators.

I am working on the following calculators and converters: tubing weight, metric/imperial, spoke length, Ackermann steering, chain length, rake & trail, and gear ratio.

If you have an idea for an online calculator, please suggest it in the forum: http://forum.atomiczombie.com/forumdisplay.php/189-Conversions-calculators-amp-more
That's all that's new here. I am looking out the window and guess what, it's gonna rain again soon!

~ Brad

The time and space conundrum

Our basement before any renos were done

Time and space are those two things that have always managed to stump the world's greatest thinkers, leaving us to the stark realization that we are but visitors on this rock, hurling through time and space at 66,000 miles an hour, tethered to a burning sphere by an invisible force in an unfathomable universe. This most of us take for granted, while refusing to believe these forces have any more effect on us than a butterfly beating its wings halfway around the world.

Yeah, I stole that quote from the X-Files and my mention of time and space here is under a different context, a more literal one; most of us need more free time and a larger space to work in! I am constantly trying to find more room for my junk (priceless parts collection) and at the same time store my creations, but there is never enough room, so often bikes are recycled for parts after a year or two. This constant shuffling of stuff then leads to my ever present lack of time, and often I just let things pile up and work around the mess since a full cleaning would take most of the day away.

After we moved into a single wide modular home, I knew that my indoor workspace would need more a lot more room; it was time for some basement renos. I have a fair collection of electronic bits for my work, so storage space and workbench room are very important. I decided to turn one end of the basement into a lab. It's always fun to share photos of our workspaces, and since I have blogged about my old bike building shack down at the bottom of the hill, I thought it would be fun to show the space I am occupying as I write this now. The lab!

Anyone who has been in a modular home knows that they are 16 feet wide and long, really long! We decided to custom design the modular to sit on a full 9 foot basement so that we would double our space and end up with huge windows, making it seem less like a basement and more like a split level. The engineered trusses are great because all of the ductwork is out of the way, 9 feet about the floor level.

All of my electronics parts, robot bits, and good bike parts ended up in the basement, since we have very little outdoor storage space. The AZ parts orders are also packed down here on the brown table. There is a decent amount of space here, but I have not had much time to organize it or do any work. I did however, get to complete my new lab recently and am typing out at you from it right now.

Working with wood instead of steel

When you are a DIY type, it doesn't matter what materials or tools you are using - you just measure three times, cut once and adapt along the way. Working with wood is certainly easier than steel, but doing a proper renovation does take a lot of research into code. Living in a Northern climate and having a 5 foot concrete wall with a 4 foot stud wall on top took some amount of planning in order to get the insulation done correctly. I had to build another 2x6 wall an inch ahead of the concrete wall and create an air barrier on the cold side then a vapor barrier on the warm side, keeping to an R24 insulation value.

Sure, I know what I am talking about now, but when I started, I didn't know the deference between an air barrier and a moisture barrier. A moldy basement was not something I wanted, so I did my research. The secondary wall took out about a foot from the width of the room, but it still ended up being 14x16, and that was certainly enough room for me to work on my technical projects and plan writing.

My new lab partially completed

I continued the secondary wall up to the top, added a suspension ceiling, lights, lots of electrical and then put down a waterproof composite floor that looked like hardwood. I was quite happy with the final results, considering much of the things I did were new to me. I still need to finish building the cupboards and workbenches, but I am quite comfortable on the temporary tables and have plenty of room to store my stuff.

So, if time permits, I will once again expand my space, enjoying the rewards of DIY and learning new skills as I move along.  No doubt, if you are the type of person who would build a bike, you probably enjoy other DIY projects as well around the house and yard. DIY is a way of life!

~ Brad