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New speedbike for Battle Mountain

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Victor Ragusila
recumbent enthusiast

Canada
337 Posts

Posted - 10/08/2010 : 14:48:59

Hey All

I am Victor Ragusila. Last year i was in charge of the UofT team, and we had a very good time at BM2010. Both me and Todd decided to build 2 bikes specially for Battle Mountain, besides the new bike for the ASME student competitions. I will document the design and (hopefully) construction of my bike in this post.

Right now it is only a CAD model, and it will probably stay that way until after BM2011, as i feel i need to learn more and build another bike for ASME with the team before building a BM-only bike.

The bike is made to be smaller than a Varna Tempest, roughly the size of Elvie3 while keeping the rider facing forward and in a somewhat normal position. It will be a camera only bike, with a linear drive.

The drive will be a K-drive based design, or a rowingbike (http://rowingbike.com/site/EN/)based design. I will first build the drive separately on a test mule and then improve it over the course of next year.

The human model shown will be tweaked to get a more natural model, and will be used together with a test bench in the design of the bike.

The pictures below show the rough shape of the fairing and the proposed structure, assuming the use of the K-drive for now.

I look forward to comments / criticism / ideas / sponsorship deals :D

cheers

Victor Ragusila

http://www.facebook.com/photo.php?pid=5727500&l=fd14ad910d&id=512761500

http://www.facebook.com/photo.php?pid=5727499&l=676863529c&id=512761500

http://www.facebook.com/photo.php?pid=5727497&l=2b6cb49e91&id=512761500

http://www.facebook.com/photo.php?pid=5727498&l=8f52efb1cb&id=512761500

http://www.facebook.com/photo.php?pid=5727496&l=d8b3d5deeb&id=512761500

http://www.facebook.com/photo.php?pid=5727495&l=0d903568c8&id=512761500

sean costin
human power supergeek

Lesotho
1919 Posts

Posted - 10/08/2010 : 17:44:25

Victor,

It looks very cool. Beautiful cad work. I'm not an expert, but slept in a Holiday Inn Express last night. My personal opinion is that the plan view indicates a shape that is a bit blunt at the nose, a bit too flat at the sides and a bit short in the tail. Are you using a specific airfoil?

Sean

Upright Mike
human power expert

USA
3007 Posts

Posted - 10/08/2010 : 19:01:01

Hi Sean,
I'm about to sleep at a red Roof - here at the Ohio races. Are you in town for the races?

Hi Victor - see the comments I posted on Facebook. Great design - it looks like a mix of the Varna low nose, Eivie tail and Wedge (Kyle Edge shape) over its body. Matt Weaver's original Kyle Edge was a camera bike as well. And I see you paid attention to Damjan's comment during the forum where he said don't leave any room left-over! Also it looks like your rider in there has Sam's shoulders, or that could be Todd's?

ZZZzzzzz - I'm off to sleep
- Mike

Dana Barlow
recumbent enthusiast

322 Posts

Posted - 10/08/2010 : 20:17:31

Hi Victor.
Things that may need more thinking.Looking at your design,here is what I think I see as problum spots;
Riders head is so low as too be very hard for rider to balance on two wheels,hands are so high that control will need a lot kecting up with and would need remote steer, linear drive design eats HP up,more then less aero drag helps.
Camera bikes are not safe and gets real bad with head very low on two wheels.
Good luck

Dana
Team Strange
"Strange One","Too Strange","Strange Try"
Miami Fla.

Edited by - Dana Barlow on 10/08/2010 20:21:15

LongJohn
recumbent guru

Netherlands
532 Posts

Posted - 10/09/2010 : 03:20:08

Victor,

Since we talked in BM about speedbikes I would like to give you advice.
Would you be able to post your pics anywere else? I don't have a facebook account and can not view them...

Thomas

Jeff Wills
human power supergeek

USA
1124 Posts

Posted - 10/09/2010 : 20:14:35

quote:
Originally posted by LongJohn

Victor,

Since we talked in BM about speedbikes I would like to give you advice.
Would you be able to post your pics anywere else? I don't have a facebook account and can not view them...

Thomas

Hmmm... Victor, see if there's a setting within Facebook that allows public sharing of photos. I think mine is set that way, and I can post photos anywhere, like this:

__________________
Jeff Wills
All my bikes:
http://home.comcast.net/~jeff_wills/Gallery/index.html

LongJohn
recumbent guru

Netherlands
532 Posts

Posted - 10/10/2010 : 02:44:51

Victor,

I was able to view the pictures. Thank you for listening in Battle Mountain... ;-)

Like Sean, I figure that you will go thru some iterations to determine a shape that has a better pressure distribution?
A good pressure distribution is key for a laminar boundary layer shape.

Thomas

Edited by - LongJohn on 10/10/2010 02:45:33

Victor Ragusila
recumbent enthusiast

Canada
337 Posts

Posted - 10/10/2010 : 09:54:46

Hey All

Thanks for the comments. I decided to share the design process early on so i could receive comments and critique, and i very grateful for them.

Sean, I did not use a airfoil shape for the top view of the bike, and i do not intend to use one. I agree that currently the nose is too blunt and the sides too flat, i will tweak those slowly. Since the shape is highly 3D, I dont think using an airfoil is really appropriate, as most were designed for wing sections. For the rear section, we used an angle of 17 degrees on ACE (relative to the center line) and we observed no separation. Increasing the angle (steeper) reduces the area, but increases separation chances. Decreasing the angle increases the area, and decreases the drag due to pressure distribution recovery. I will run some CFD and/or experiments to tweak the tail angle, but so far i am happy with anything that is short and doesnt separate the airflow.

Dana, the rider will stay higher than in a Varna, but more horizontal. Looking at some of the low racers at IHPVA events, the position doesnt seem that extreme, but i will follow your advice and set up the test bike with the same configuration and see if it is controllable/comfortable. The bike will have a linkage steering, such that a big hand movement corresponds to a relatively small angle change of the wheel (2:1 ratio probably). This i think will increase control over the bike.

The camera is necessary i believe. I do not want to build a Varna clone, as i will not be nearly as strong as Sam, and i want to go fast. I think a 3 camera set up (1 frontal and 2 on the sides) with three screens, or 1 camera with 2 side windows is good enough for BM.

The linear drive is a Holly Grail that i think very few designs got close to (Arrowhawk being one of them). After playing with the linear drive from the rowingbike that we used on the ornithopter, i believe i can build a very small, 90+% efficient design. Not as good as a chain-only transmission, but it allows the smallest possible nose section. Whether that loss of efficiency is bigger than the aero gain is of course the big question, and i have no data to back up my choice as of yet.

Thomas, the aero shape is not nearly finished yet. The steps in aero development i see so far are:

1) get the shape of the human much more detailed, both from the model and from testing on a bench.

2) build a scale model. Test it (on top of car or airtunnel) to see whether the nose is in the stagnation point, and to see if the streamlines are where i would like them to be. Check the accuracy of the CFD to predict streamline directions. Also test for separation at the back of the bike.

3) finely tune pressure distribution on the nose to get laminar flow as far back as possible.

4) test airflow around the wheels. I will probably build the front wheel cover for the ACE and test it. The rear wheel will be faired as much as possible.

5) build bike. Test wheel fairings/wheel disks and wheel wells on the finished bike. Also test whether laminar flow was achieved.

thank you all for comments, please keep them coming :D

Victor Ragusila

Edited by - Victor Ragusila on 10/10/2010 09:55:30

purplepeopledesign
recumbent guru

Canada
568 Posts

Posted - 10/10/2010 : 10:15:33

So... does the rider know in advance that shoulder contortions will be an absolute necessity?

:)ensen.

Those who claim to be making history are often the same ones repeating it.

Video of my trike
http://www.youtube.com/watch?v=MdSLRD_2vzc
Photos of my trike
http://www.flickr.com/photos/purplepeople/

Victor Ragusila
recumbent enthusiast

Canada
337 Posts

Posted - 10/10/2010 : 10:31:56

The shoulders stick out simply because my CAD model has normal shoudlers. I will modify it to represent a rider with squished shoulders after i measure what is comfortable for me and Todd. Right now there are 15in shoulder width. I can easily fit in that, and decreasing it doesnt help much with the shape. Next week i will build a test bench for the ASME bike and we will test necessary shoulder clearances.

raymondg
recumbent guru

824 Posts

Posted - 10/10/2010 : 18:25:51

A note on shoulder width: Make sure you are exerting yourself hard and breathing heavily when you measure your minimum comfortable width. I think that's an advantage of the Varna position amongst others: The shoulders are extended above the thorax instead of being squished into them, allowing freer breathing while minimizing fairing width.

-Raymond

Dana Barlow
recumbent enthusiast

322 Posts

Posted - 10/10/2010 : 20:24:44

On testing,some forget about limit of movement both body and head. It's amazing how much we use our head to balance on a open lowracer,this inside a fairing is often not roomy enough=can't balance well that low/ other thing that is very real world is the lower your ear[balancing] to the ground,the less time your have to adjust for balance=feels very high speed twich.
Witch brings me to steering at anything other then 1 to 1,after much playing around my self,find that feel is much better at 1 to 1 vs other. That gets even more so for many riders vs only one.
Camera's are a crash that will happpen,I'd like to see them outlawed.

Dana
Team Strange
"Strange One","Too Strange","Strange Try"
Miami Fla.

Edited by - Dana Barlow on 10/10/2010 20:26:43

Victor Ragusila
recumbent enthusiast

Canada
337 Posts

Posted - 10/10/2010 : 22:02:00

quote:
Originally posted by Dana Barlow

On testing,some forget about limit of movement both body and head. It's amazing how much we use our head to balance on a open lowracer,this inside a fairing is often not roomy enough=can't balance well that low/ other thing that is very real world is the lower your ear[balancing] to the ground,the less time your have to adjust for balance=feels very high speed twich.
Witch brings me to steering at anything other then 1 to 1,after much playing around my self,find that feel is much better at 1 to 1 vs other. That gets even more so for many riders vs only one.
Camera's are a crash that will happpen,I'd like to see them outlawed.

Dana
Team Strange
"Strange One","Too Strange","Strange Try"
Miami Fla.

hmm, good point about testing with limits. I will try to come out with a good way to test handling and limit shoulder/head movements.
What type of steering ratios have you guys played with and why didnt they work? I am curious to know what was done before...
Cameras are difficult to deal with, but 2 cameras on independent circuits and side windows should be reliable...me thinks...

Anyone tried periscopes? or fiberoptics periscopes? or anything else that would not require a bubble canopy?

cheers

Victor Ragusila

sean costin
human power supergeek

Lesotho
1919 Posts

Posted - 10/11/2010 : 05:06:20

Victor,
I have been studying periscopes for a while. I don't think I will be going down this road, but If I were to build something that needed a periscope or a camera, I'd pick the periscope. Periscopes are simple and very little can go wrong. A great deal can go wrong with a video system in a very high vibration environment. Cables can come loose and any one of hundreds of electrical connections, solder joints or electrical components and batteries could fail on you. It is typically a high maintenance method of vision. Your monitor is also subject to the same high vibration so it becomes difficult to stabilize the image with your head. The video glasses would be a better choice for this reason , but you would have to whip them off to view a secondary monitor in case your glasses fail.

A simple mirror system is possible and has been used, but field of view is not very good and the image is significantly darkend. Tank prism telescopes are massively heavy solid trapezoidial prisms.

WW 2 binocular Trench periscopes are a possibility. They incorporate a relay lens system in the shaft that significantly improves field of view over a basic mirror system. They are also heavy steel and large. They can be widened like rabit ear antennas to improve depth of field and field of view. They are usually a $200-$400 dollars on ebay and in various states of condition.

This search led me to discover two light weight options. The sport periscope and the inspection periscope. Both lens based systems. I ruled out the sport periscope because it was too tall.

http://t3.gstatic.com/images?q=tbn:tzmPMHDXyAiB1M:b

The AVscope inspection periscope seems just right to me and is quite light and affordable. I would buy 2 and make them binocular and mount them passively to the rider's head with an elastic band around the head and a padded facial support that contacts the forehead and cheeks. Pretty much like a submarine periscope interface. There is a 3x magnification version as well. This periscope seems to always be available on ebay. After the auction expires, it gets relisted. The price is $75.00 plus shipping. I am having problems posting images directly to the forum for some reason.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=300468570680

Good luck. I hope you or someone else can take advantage of the many hours of research I have done to this point with periscopes. Note that I have not tested anything, so if you do testing please share it with this forum.

Thanks,

Sean

LongJohn
recumbent guru

Netherlands
532 Posts

Posted - 10/11/2010 : 07:59:26

Sean,

I am not sure you could consider a periscope mounted (although passivly) to the riders head very safe...
The rider will most likely damage his/here eyes or face in the event of a crash, even with padding.

When you incorporate two mirrors as a periscope within an otherwise dark bike, with the top mirror having a slight curve so it increases field of view. Would that not give you enough field of view to keep the bike upright?

I know that periferal view is very important, would the curved mirror satisfy that requirement?

Interesting subject, since manufacture of a windshield is very costly, and time consuming...

Thomas

Larry Lem
human power supergeek

South Sandwich Islands
1971 Posts

Posted - 10/11/2010 : 08:04:41

Similar to Raymond's note on shoulder width,

A note on pedaling clearance:
Make sure you are accounting for the pedal strokes getting a little wild which can occur after a few minutes in the red zone, and then almost passing out. Once one part hits (knee, heel, outer toe) things really go to hell and you have to back off to get control of the motion again.

For this reason, folks like to keep rpm down below 110, maybe closer to 100. But then you need longer crankarms (if using a conventional crank) to produce the torque and power, which drives the streamliner height up again.

Now you'll have the more-complicated drivetrain to compound the development in this area.

Larry Lem

Edited by - Larry Lem on 10/11/2010 09:21:43

sean costin
human power supergeek

Lesotho
1919 Posts

Posted - 10/11/2010 : 08:47:05

Thomas,
Right after I hit send. I thought. I should mention that the periscope should be break away itself or mounted on a break away panel. I do not know about the effect of curved mirrors. My experiments with simple mirror configurations have been disappointing. I'll see if I can photograph the effect. In any case, the mirror must be placed very close to the eyes.

Sean

Speedy
recumbent guru

USA
656 Posts

Posted - 10/11/2010 : 12:40:26

Victor
your CAD work looks nice

regarding low drag shapes:
our group has done a fair amount of work on fuselage shapes only to find that there is not much (if anything)to be gained in spending much time defining "the perfect shape"
i.e. the sculpture's eye is very much valid

the basics: small frontal area, small surface area, gradual changes (fillets), no internal flow

linear drive ...
before committing to this format do plenty of testing, verify the power at the wheel as compared to power input from the human ... I suspect, the smaller frontal area won't be enough to compensate the lower input power and drive train losses
think of this way:
there is no restriction on drive train systems for an upright "pro" bicycle ... if it made more power it would be in the Tour de France or national time trials

the biggest advantage the faster bikes have right now is the human model is clearly defined
Sam fits his bike precisely, is well practiced in his pedal stroke so in can be accurately measured

happy building :-)

E.B. Erickson
Starting Member

47 Posts

Posted - 10/12/2010 : 04:54:36

Didn't the Aussies use a periscope on one of their streamliners last year? I seem to recall their racing on a track in Oz with someone's teenage son as the pilot. The streamliner may have been one of the Wedges (?).

--ElJay

LongJohn
recumbent guru

Netherlands
532 Posts

Posted - 10/12/2010 : 05:59:58

See Tuesday, April 10, 2007;

http://whoops160.blogspot.com/search?updated-max=2009-10-05T20%3A43%3A00%2B11%3A00&max-results=7

I still think this could be an interesting concept (the use of a periscope).

Thomas

Dreamer
recumbent guru

USA
541 Posts

Posted - 10/12/2010 : 23:15:08

This has been an interesting thread with a wide variety of topics to comment on.

James has experimented with video goggles in both the Specter II and the Arrow Hawk. Even with our shock absorbing ride the vibration magnified and made it impossible for the eyes to stay focused. We've never had a similar problem with the cockpit mounted video screens. Even on rough roads the image is clear. I think periscopes attached to the rider's head would have similar vibration problems but attached to the vehicle the break away system would be problematic.

I disagree with some of the opinion presented on cameras. Modern technology has developed reliable video products that are being readily assimilated by the automotive world. Without proper cockpit design, wind screens, bubbles, mirrors, and periscopes can all fog up as readily as a video screen. With quality components installed in 2 totally independent video systems an instant and simultaneous failure of units in both systems is highly unlikely. I would venture that the high quaility wide angle cameras and HD video systems our riders have offers a higher quality view of the road than many riders have looking through a blown bubble from a reclined position. We have comfortably test ridden our camera vehicle on residential streets and on both rural and 4 lane major highways.

The vote is still out on our eliptical/linear drive. In theory it offers more power per pedal stroke than a rotary crank but we don't know if that's enough to offset the extra power to run the drive. We run 165 cranks with a foot box sized for 145s and a power stroke comparable to 185s. We do know the drive is sufficient for amatuer riders to easily power a couple of the biggest single rider streamliners ever made down the Battle Mountain course at respectable speeds. James is building experimental equipment that should allow us direct measurement comparisons. We'll bring the results to BM 2011. <G>

Last comment would be that balance in a streamliner is an acquired skill that's not always essential and quality of the product seems to be the major factor whether piloting with direct vision, mirrors, or video systems. As our first time riders have shown balance and experience are not the major limiting factors in a user friendly streamliner design.

Don

quote:
It's important to understand what makes them fast. It's more important to understand what keeps them from being faster.

warren
human power expert

4230 Posts

Posted - 10/13/2010 : 06:02:38

The biggest issue IMO with the camera bikes is video time lag. There is a short time delay between when the camera takes the picture and the rider sees it. In a laid back completed sealed streamliner the rider is relying more on visual cues than inner ear to balance the bike. When those cues occur after the event happens, corrective actions happen late, and can result in unwanted oscillations. Newer video systems may minimize this issue, but testing would be required. As Victor notes, side windows do help to minimize this issue.

-Warren.

LunaticFringe
recumbent enthusiast

USA
366 Posts

Posted - 10/13/2010 : 09:03:59

Also, keep in mind that if you use a camera system, have it be 'hard wired' and not based upon FM signal transmission. The soil in Battle Mountain messed with my FM signal based camera system (lots of iron?) to the point where the static was so bad that I couldn't use it. Gardner Martin attempted to save the day and loaned a wired camera system to me. I couldn't adapt it quickly enough and had to cut a hole to stick my head out of the fairing just to get a run in. Ah, the fun of it all!

Jeff / Lunatic Fringe Streamliner

calfeenated
recumbent enthusiast

205 Posts

Posted - 10/13/2010 : 22:08:20

A word on periscopes...
Eric and I tried a periscope in the wedge before we rebuilt her.
It was simple to make and we only got to test it while running on a very bumpy road at low speed and it did help eric see over the nose of the wedge but the bike had too many other issues and we just resorted to a regular canopy in the end but...
I believe their potential is very workable. We used plastic mirrors that would pose no risk to the rider in a crash.
If anyone has issues about vibration causing distortions in them they should make a visit to their local drum shop and buy a few packs of moongel. Drummers stick this stuff on their drum heads to absorb some of the overtones and to control the amount of ringing. I have found dozens of other uses for it, anyplace you want to absorb vibration this stuff rocks.
I had a guitar player complaining about the springs inside his guitar ringing when he'd hit a certain note. We stuck a pad of moongel on the springs and it was gone. I stuck some inside an amplifier who's fan was vibrating the entire chassis and bam it was gone just like that. Stick some moongel on the back of the mirrors on a periscope and I'd bet any vibration issues would be gone too.

Mark.

raymondg
recumbent guru

824 Posts

Posted - 10/13/2010 : 22:41:45

Sounds like interesting stuff this moongel. Did you use any on the Wedge?

-Raymond

Edited by - raymondg on 10/13/2010 23:06:11

calfeenated
recumbent enthusiast

205 Posts

Posted - 10/14/2010 : 21:46:59

Not this year. I might use this stuff in the landlord trike though.
I'm considering molding some into the top fairing to remove some vibration.
how goes the orion rebuild?

Mark.

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