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GOALS, RULES AND TECHNOLOGICAL INNOVATIONBy Paul B. MacCready

(Presented at the 1986 World Congress on theMedical and Scientific Aspects of Cycling, Col-orado Springs, Colorado) September 2, 1986.

ABSTRACT

Competitive events have a strong influenceon the development of a sport, even on non-competitive aspects. Paradoxically, while com-petitions stimulate technological innovation,rules tend to inhibit innovation, and yetcompetitions must have rules to promote safetyand fairness. Clues about the possible futurecourse of cycling technology come from exploringcycling's past and from the development of othersports that are also based on technology invol-ving structures and aerodynamics, such as sail-planing, hang gliding, and sailboating. Forhigh-speed-cycling competitions, the definitionof a bicycle now presents a major dilemma:specifically, what aerodynamic improvements areto be permitted (related to the question ofwhether racing success is to be based on humanprowess or technological advantages)? Specify-ing a minimum drag at a high speed rather thanspecifying design details is a possible way outof the dilemma, but the concept has problems inmeasurement and in public acceptance. Industry,educational and research institutions, andsports organizations will continually be linkedwith inventors and cyclists seeking the bestcompromise on the rules that serve to coordinateand stimulate cycling. The goal of simple,fair, unchanging rules must be sought even if itproves unattainable.

INTRODUCTION

The technology of cycling can include notonly the vehicle but also the rider who powersand guides the vehicle, the rider's training,the use of the vehicle for recreation or com-petition, and the underlying research, devel-opment and manufacturing. We will focus here onthe vehicle, while still considering the usersand suppliers. Our aim is to explore factorsrelated to stimulating cycling, especiallythrough technological innovation. (We implicitlyassume cycling's growth is a worthy cause). Theexploration includes considering what cyclingis, how rules determine technology and how theycan either invigorate or stultify innovation,and how several other sports have handled com-promises of rules. We then contemplate what allthis means with respect to cycling, and suggestsome recommendations and conclusions.

Motivation is, of course, the primary drivefor technological innovation and arises fromboth psychological and economic factors. Forcycling, motivation includes the ego drives ofcompetitors, the enthusiasms of researchers,economic goals of manufacturers, recreationenjoyment for the sporting participant, conve-nience for commuters, and the innate character-istic of humans to brag about equipment.

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In This Issue...

Goals, Rules and TechnologicalInnovation

Paul B. MacCready ...........................1Editorial Comments

David Gordon Wilson ....................... 2Letters ........................................................... 3A Human Powered Footin the Door

Peter Ernst ..............................................AVentilation of Streamlined HPVs

John Nobile ................................. 5Development of an AerodynamicBicycle Fairing

James Donahue................................6Caf6 Racer, An Unusual Approach

Marten Gerritsen andMarinum Meijers ................................... 7

Design and Test of a HPB PropellerDavid Gordon Wilson ..................... 10

News .. .................................. 19Major Taylor -an Extraordinary Champion

Andrew Ritchie ................................. 2-J

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HUMAN POWER, Summer, 1987 vol. 6 no. 2

TABLE I: FINAL DESIGN OPERATING CHARACTERISTICS

speed I tip I hub(m/s) I lift I lift

2.2

1.0

0.5

0.4

0.95

1.29

0.4

1.36

1.5

I thrust I eff I powerI (N) (/.) I (w)

49.0

65.83

63.62

83

65

34

129.75

100.0

91.19

I rpm I torqueI I (N*m)

250

192

174

4.95

5.0

5.0

TABLE 2:BLADE DIMENSION

station radius chord

no. (mi) (cm) I

1234

56789

10

C2o

}- 1o

a

0.040.060.080.100.120.140.160.180.190.20

8.348.949.108.748.006.985.694.042.931.00

TABLE 3: FOIL-SELECTION

angle

(deg)

62.0452.5544.7138.3333.1828.9825.5322.6721.4220.25

THICKNESSNHR X/T

I 1. 0030oooo2 .998933 .995724 .993395 *982966 .973477 .961948 .9,18449 .93301

10 .9157311 *8:966812 .8753213 .8535514 .8296715 80o43816 .7777917 . 7 500018 *7211 419 .6913420 .6607221 .629412_ .597b523 .5652624 .5327025 .5000026 .4673027 .4347420 .4024529 .37J5930 .3392831 .3006632 .27sUb33 .2500034 .2222135 .1')56236 .1703337 .lI611538 .124J839 .1033240 08n4d741 .0669942 .051b643 .0380644 .0265345 .0170446 .00;96147 .004q848 .0010749 .00000

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TABLE 4: -TEST RESULTS

TABLE 4: TEST RESULTS

COEFFICIENTSYU/T YU/T

.00000 .000 0

.04316 .0000"

.00065 .00016

.C0153 .00027

.00288 .00033

.00471 .90030

.U0697 .0 0 0 1qC00958 .00002*.1247 -. 0017.U156 -. 00036.0195 -. 00057·02254 -. 00081.02635 -. 00110.03039 -.00148·03162 -.001q3.03901 -.00247.041355 -. 00399.04818 -.00591.05285 -.00461.05753 -.00549.06215 -.30b47

.066b4 -. 00759

.07093 -.00864

.074S0 -.00983

.07821 -. l01ab

.08100 -.01233

.08310 -.01362

.08445 -.o014 1

.08509 -.Olb18

.08475 -.01740

.00369 -u185bU00107 -.01962

.07938 -.32056

.LU7631 -.02135

.0727c -.02196

.0b861 -. 02236

.06408 -. 02255

.05918 -.0224"

.05393 -.02200

.04837 -.02145

.04264 -02045

.03670 -. 01901

.03G33 -.01753

.02462 -.01569

.01071 -.01277·01210 -.01324.OCG66 -.00750.00303 -. 0012.0003 .00000

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WHAT IS CYCLING?

Human power can be used for moving a personon land or water with or without a vehicle.Cycling is a special case of a vehicle havingwheels and moving over the ground. It is usefulto consider human-powered locomotion from alarger framework so that the cycling portion canbe better illuminated and defined.

A person swims in water, but can movefaster with the aid of swim fins, webbed gloves,and certain wing-like devices operated by thelegs. More complex devices eventually consti-tute vehicles. Some rare boats are propelled bylegs, but most involve arm-operated paddles oroars: paddleboards, surfboards, kayaks, racingshells, and rowboats (and to be complete, even300-man oared boats from several thousand yearsago).

As for land, there are skis and snowshoesfor snow, and skates for ice, while for ordinarysurfaces there are bare feet, "human-poweredshoes" in great variety, stilts, pogo sticks,skateboards, scooters, and cycles with 1-,2-,3-,or 4-wheels (mostly leg-driven, but some, suchas wheelchairs, using arms). One can even addsomersaulting and walling on one's hands andnote the application of human power to mountainclimbing.

Human-powered flight requires a vehicle. Thevehicles at present are all large, light-weight,propeller-driven devices.

To complete the picture, note that animalsother than man provide power for vehicles, usu-ally to move man or some load of interest toman. Sometimes muscle power is augmented, aswith electric motors, or gasoline engines.Small fossil-fuel engines can generate tens andeven a hundred times as much power as a personand can permit a vehicle to have better perfor-mance, and be heavy, rugged, and safe. Batterypower is more limited but still packs much morewallop than muscles and has the added potentialof regeneration from braking or charging fromon-board photovoltaic cells. Sometimes wind orwave motion is harnessed to help propel avehicle that also uses human power.

Finally, we need to note that gravity,through non-horizontal terrain, plays a signi-ficant role in cycling. Climbing uphill takesextra power at the rate of weight times verticalascent speed. Moving slowly on foot, the extrapower is considerable; moving fast on a bicycle,the ascent speed can be large and the extrapower requirement huge.

Thus there is a whole spectrum of powersources for apparatus and vehicles that trans-port people, from relying 100% on human musclesto 0%. Here we focus on bicycles powered solelyby muscle, while recognizing that some inter-esting technological innovations may arise froma bit of augmentation by electricity, fossilfuel, or wind. If the augmentation dominates,the we end up with a car or motorcycle, whichmay be practical but which eliminates the exer-cise benefits and challenges of cycling.

Man is inefficient as a runner. With effi-cient mechanisms (bicycle, ice skates) he canmove about twice as fast as running, to a spedwhere air drag starts to dominate. Then, with astreamline fairing, the speed can be doubledagain. The inefficiency in running is due tothe loss of potential energy with each step asthe center of gravity is raised and loweredwithout effective energy storage and recapture,and poor recapture of the kinetic energy ofmoving limbs.

The bicycle is an extremely efficient mech-anical device for deriving power from the rider.The constant center-of-gravity position elimi-nates the potential energy loss each cycle,while the pedal-chain-wheel-inertia systemavoids the kinetic-energy loss. The bicycle,with its large diameter low-drag wheels, is alsoextremely efficient as a device for moving overa smooth, hard surface. No shoes, scooter,skateboard, roller skates, or pogo stick offersthe combined effectiveness of a bicycle in powerextraction and motion efficiency. Vehicles withother than two wheels have special features:the unicycle emphasizes fun with great demandsin skill: three and four-wheel cycles emphasizestability for less agile cyclists and in somecases a great load-carrying capability which isused commercially, especially in other coun-tries.

The bicycle readily reaches a high enoughspeed that the standard vehicle is fun to ride,useful for sport, touring, commuting, and exci-ting competitions. It is a wonderful device tolure people into healthy exercise. In races,however, the speeds are such that aerodynamicdrag becomes a dominant factor. Thus vehicledesign looms large, and the troublesome chal-lenge for rule-makers is to provide definitionsand limits for vehicles so that winning cyclistsare fairly selected.

Design evolution and the IHPVA:analogy to natural evolution

Given enough time to for development,entities evolve, within the constraints of phy-sical law, to fit a desirable opportunity.There is a close analogy between the way goals(rules, motivation) stimulate or inhibit tech-nical developments and the way the characteris-tics of a particular ecological niche in nature(the coal limits, opportunities, andcompetition), serve to design the creatures that fillthe niche.

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T-TITAlfA\ PwpR Cirmmpr 1997 unl- A no 2 nage 13

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Evolution of creatures, devices, or ideasworks on the simple basis that things whichleave descendents are those which work wellenough to survive the competitive pressures andleave descendants. There is no right or wrongand no perfection, just the criterion of rela-tive success. Whether the law of the jungle orthe law of manufacturers' economic competitionis involved, what succeeds In nature,the ecological niche establishes the rules; anysolution can enter the fray and will be scoredversus competitors. In man's technology, withdevelopment staking place thousands or millionsof times faster than in nature, the economics oflarge-scale manufacturing is a strong forcingfunction and this market depends on standardizeddemand and hence on the existence of rules andadvertising.

Almost a century ago, after several decadesof design innovations, the conventional "safetybicycle emerged with its two equal-size tan-gent-tension-spoke wheels, pneumatic tires, andchain-driven rear wheel. The standard bicycleof today differs from this ancestor only indetail; except for the gear shift, the changeswould scarcely be detectable to the casualobserver. One reason the 1986 and 1886 bicyclesare similar is that the 1886 version was sogood, being efficient, safe, easy to ride, easyto store, and simple and inexpensive to build.But another reason is that bicycle competi-tions,which tend to set technological standardseven if only a small percentage of cyclistscompeted, dictated that the vehicle bestandardized (Therefore not be improved) so no riderwould have an unfair advantage. Like a speciesof animal, the multitude of these satisfactorybicycles fitted well their broadly based andeconomically driven "ecological niche" and thedesign evolved only very slowly and in minorways as the decades went by.

One modern view of natural evolution has anew species sometimes evolving out of a stable,established species via a major, rapid, adaptivechange labeled "punctuated equilibrium". In asuggested scenario a small group of animalssomehow has to operate in isolation from themain group, in a circumstance where differentecological pressures are found to be especiallyfavorable to certain inheritable genetic aber-rations or traits. The genes (the carriers ofthe creature's design to the next generation) ofthe odd superior individual in the large popu-lation get submerged in a massive gene pool andhave little effect. But in a new, small, iso-lated ecological niche, the superior individ-ual's superiority can be relatively more impor-tant for survival, the individual's genes willbe less diluted in the small population, and inrelatively few generations a new species canevolve. Eventually the new species may evenspill over into the large original ecologicalniche, prove competitively superior there, andcompletely supplant the original species.

In 1975, the IHPVA was formed to stimulatethe development of fast human-powered vehicleswithout the inhibiting effects of rules. Thesole criterion of success was "going fast",withno concern about the mechanism or configuration.The resulting evolution of new designs wasrapid, as a small number of inventors (initiallyin Southern California) found what worked inthis new isolated "ecological niche". Fantasticspeds are now being achieved (65 mph, 105 kmh);equilibrium was "punctuated".

After a few years of strictly speed compet-itions, IHPVA added competitions for "practical"vehicles. The definition of "practical" isstill in a state of flux,as are the criteria forjudging the vehicles, but the overall aim isclear: a human-powered vehicle that offerssafety, speed,versatility, comfort, and economy,and that would be attractive both to commutersand long-distance riders. A new"species" onlycan evolve from this competition if a designemerges that is so satisfactory it becomeswidely manufactured; no such design has yet beendemonstrated.

For half a century there have occasionallybeen isolated pioneers showing that streamlinedfairings permit high speeds or that unusualconfigurations show promise for meeting a spe-cific customer's desires, but such aberrationshad negligible impact on conventional bicycles.Serious developments of mainstream touring,sporting, and racing bicycles were economicallydriven and tended to be ones that could be com-fortably assimilated into the mainstream, such asthe ten-speed derailleur and improved brakes.The major trends that kept cycling healthy overthe last few decades have been popularization ofvariations on the theme of the conventionaltwo-wheel bicycles with standard seating posi-tion. The economy and versatility of the ten-speed gearshift brought many customers into thefield; BMX bikes for competition and rough usearound town have created a substantial new mar-ket; and mountain bikes are a recent successstory.

IHPVA has popularized an enthusiasm forgenerating significant change and, with itscompetitions, media interactions, newslettersand technical symposia, has stimulated inven-tors,cyclists, manufacturers, and universitiesto explore technologies for the future. Theinternational publicity accorded early IHPVArecords no doubt helped stimulate the aerody-ramic innovations for standard bicycles whichbegan in 1976. By 1978, aerodynamics, tubing,clothing,and helmets were commonly contributingto higher speeds. Dr. C.R. Kyle, co-founder ofIHPVA, has been a significant contributor to thetechnology that in 1984 produced the U.S. Olym-pic bicycles.

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nage 14 HUMAN POWERX, Summer, 1987 vol. 6 no. 2

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RULES AND THEIR EFFECTS

In 1938, the Union Cyclist Internationalestablished rules against recumbents andstreamlined fairings in racing. After the 1976developments cited above, in 1978 the UCI"loosened the tourniquet" on the prohibition ofaerodynamic features. In 1984, an aerodynamicrule milestone (or millstone, depending on yourpoint of view) was achieved when Moser was per-mitted to set an official one-hour record atMexico City with a bike that had been tailoredin a wind tunnel and featured solid wheels, andsubsequently similar Olympic bikes wereaccepted. The door for innovations via aerody-namic modification has certainly been opened asignificant amount, but at the cost of somecontroversy about the past decisions and ques-tions where this all leads, about what ruleswill best serve the purposes of cycling.

There is also the question of the criteriafor competition. In a team sport, such as soc-cer, the winner is a team, not an individual. Ina 100m freestyle swimming race, the winner isclearly th the individual. For a fairedbicycle/tricycle speed event or a human-poweredairplane challenge, the vehicle is a major partand the prize or honor is usually shared by therider and the vehicle developer. In the Tour deFrance, an individual wins, but aided by histeam. In international sailplane competitions,radio communications permit the several compet-itors from one country to coordinate thermalhunting and give an improved chance to each ofthem and a still larger chance to a particularone. Such coordinating communications complicatethe issue of whether the winner is an individualor a team. This coordination is done by somecountries with well-disciplined teams; withother countries where discipline is lesscharacteristics and where the competition is clearlyconsidered as selecting an individual winner,the radio is not used for "collusion" purposes(and a competitor may even use it to mislead hiscompetition while also gleaning from it whateveruseful information he can).

It seems logical to adopt the general prin-ciple that the official winner(s) of a competi-tion is the individual or group whose effortswere dominant in determining the winning. Forsolo events where no apparatus is required, suchas swimming and running, or where the apparatusoffers no special advantage, such as tennis,bowling or chess, the principle is straightfor-ward to apply: the winner is the winner. Forteam events, the team is clearly the winner. Inevery case, a coach/trainer may have made asignificant contribution, even masterminding afootball triumph, but the competitor(s) gets theofficial reward. Where the apparatus makes aunique contribution to winning, thedesigner/developer (or sometimes the sponsor)gets some or most of the plaudits.

Categories promote competitors reasonably.The hare races the tortoise only in myth.

Categories based on size or weight or age or sexare easily defined. Categories based on expe-rience or ability are generally harder todefine, and there is continuing controversyabout amateur vs. professional. Categorizationis brought to a high level in BMX racing: agegroups, subdivided into novice, intermediate,and expert classes based on the number of topfinishes in a lower class.

Where the rules must also consider appara-tus, categorization can get sticky (except wherethe competition is about apparatus, as with theIHPVA speed event). Sailboat races between Hobi16s or Cal 40s or Star Class boats should befair, but questions do arise. One competitormay have better sails or a wider choice ofsails. The rules committee has to decide whatis permitted. For the Star Class, small impro-vements in design have been authorized that helpkeep the class technically up to date and thatallow manufacturers to sell new models withoutwiping out the class.

Sailplane competitions have provided astrong stimulus for that sport since the firstglider competitions in 1920 in Germany. Throughthe 20s and 30s, and then after WWII, bothcontests and record attempts produced develop-ments and performances that could not even havebeen dreamed of by the first pioneers. As thegliders became more efficient, the pilotslearned how to locate and exploit upcurrents,first to stay aloft longer, then to fly further.The need for speed as well as efficiency drovethe designs to higher wing loadings and toadvanced structural concepts to provide safetyeven in the severe weather wherein the best liftwas found. Regulations arose for safety rea-sons, in the form of certification for both thevehicles and the pilots. Before about 1950,contests considered duration, distance andaltitude; thereafter, the focus was on distance,which in effect combine all three. As distancesgot greater with improving vehicles,instrumentation, piloting strategy, and meteorologicalunderstanding, speed events were added, espe-cially closed-course speeds that kept the sail-planes from venturing inconveniently far fromthe contest airport. There were no one-designcompetitions because there were so few vehiclesof one type until the Schweizer 1-26 becameubiquitous. Competition categories did arise inthe 1950s. There has always been the open class.Now there has been added a "standard" class(15m span, no flaps) and a "15m class" (likeopen class, but span limited to 15 m). Alsothere are now some initial competitions withself-launched (auxiliary-powered) sailplanes.In addition to the stimulus of sailplane com-petition, there are awards for achieving certaindistances, durations, or altitudes (the Gold C,Diamond, etc.). Sailplaning is just a hobby, butthe forces for innovation have been so strongthat the technological advances have been huge.Modern openclass sailplanes, with 22m wingspans,glide as flat as 60:1 and, using thermals,complete triangle courses of hundreds of kilo-meters at average speeds exceeding the 130km/hr.The vehicles can cost more than $50,000, even

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HUMAN POWER, Summer, 1987 vol. 6 no. 2

a e1 UA OESmer 97vl o

before the instrumentation (including aflight-optimization computer) and radios andnavigation gear and oxygen equipment are added.

The growth of hang gliding was rapidthroughout the 1970s. The first contests weremore the equivalent of picnics or get-togethers,but they served to fire the imaginations ofeveryone present. The only scoring was for spotlandings and later bomb drops with bags offlour. The real goal was safe and pleasantflights with hang gliders having beautiful,individualistic appearances. By the mid-70s thesport had matured to where the manufacturerscombined voluntarily and established the cer-tification of safe vehicles, while clubs sup-ported a national organization to certifypilots. The safety record improved. Contestsbegan focusing on aerial maneuvers, duration,and distance. Vehicle performance improvedmarkedly. A small number of contest partici-pants kept pushing manufacturers to better per-formance limits, but the larger number of sportpilots pushed manufacturers on a differentcourse focused on control and comfort. In theU.S., the field has been getting smaller sinceits heyday in the late 70s. Liability problemscontributed to the decline, and also many pilotsdiverted into powered ultralight aircraft,sailplaning, and regular lightplanes. For hanggliding, the main benefit from rules was theimprovement in safety.

THE HEART OF THEDILEMMA IN CYCLING

The simmering pot of aerodynamic improve-ments boiled over in 1984 when the UCI made acontroversial decision and accepted a recordmade with a disk wheel. The rules permitteddesign changes for structural reasons but notaerodynamic reasons. (General rule 49 state,"..the use of protective shields, wind brakes,bodywork or other devices on any part of thebicycle ... for the purpose of reducing windresistance shall be prohibited.") By omittingspokes,and making the outer shell structural,the disk wheel was made "legitimate." Its sig-nificant aerodynamic benefits were achieved,allegedly within the constraints of the rules.A spoked wheel covered with non-structural lids,essentially identical in structural function andaerodynamic function, would be illegal. Whoknows what the regulatory body would decide inthe future about a spoked wheel with sturdy lidsadding significantly to the structure. Design-ers and manufacturers now need to investresources based on guesses about the rulesinterpretations of the future. The same goesfor streamlined handlebars: supposedly builtwith an airfoil cross section for structuralreasons, actually made that way for aerodynamicreasons (and apparently with little concernabout the danger from the sharp trailing edge inan accident).

If you asked 100 cycling officials, compet-itors, and manufacturers the question, "Are disk

wheels and streamlined handlebars made becauseof structural benefits?" you would get 100"nos"; if you asked, "Are they made because oftheir aerodynamic drag benefits?" you would get100 "yeses. If you asked whether the diskwheels and streamlined handlbars fit either theintent or the letter of the UCI rules therewould be some differences of opinion the rulesare somewhat ambiguous, and so various inter-pretations are possible). If you asked whetherthey are good for the sport, there would also bedifferences.

The year when a structural change was madefor obvious aerodynamic reasons, yet accepted aswithin the rules, was 1984. A philosopher,examining the implication of the decision whichin effect ignores the contradiction in "Aerody-namics is structure," would probably note theconnection with another "1984": George Orwell'sclassic book. Orwell introduced us to "dou-blethink," with Big Brother coaxing/coercin usto see no contradiction in phrases such as Waris peace" and "Ignorance is strength."

Increasing speeds, records, new heros, andnew technology all help vitalize a field, lurein participants, and fuel manufacturing. Thenew aerodynamic bicycles and clothing/helmetsprovide such benefits, but there is a questionabout where all this leads. Track meets, mar-athons, and jogging are all part of a fieldwhich has grown healthily, without controversyabout equipment. Tennis is another sport whereequipment is not expensive, and skill, not tech-nology, determines the winner. Does cycling needaerodynamic improvements? A big stimulus toU.S. cycling this year was Greg Le Mond's Tourde France victory. Would this stimulus havebeen altered by disk wheels on all participantsrather than spoke wheels? I doubt it. Annualrecord breaking could be assured if the ruleswould feed in a little more use of aerodynamicfairings each year, but I suspect the negativesof such an approach would outweigh the bene-fits.

RESOLVING THE DILEMMA

To resolve the dilemma for the rest of thiscentury requires input of people involved in allphases of cycling, especially those with theperspectives of philosophers and the mythicalwisdom of Solomon. In the definition of a rac-ing bicycle, there is no simple solution, and nopleasing everyone, but the problem must beresolved. I find it disturbing to have observeddesigners paying much more attention to how topush the edges of the existing rules, how toexploit ambiguity, than to how to straighten outthe rules.

Now the dividing line between cycling com-petitions as human skill/stamina events and astechnology events must be clarified. Pandora's

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HUMAN POWER, Summer, 1987 vol. 6 no. 2

Box has been opened and mischief will prolifer-ate unless wisdom is applied. My prejudice isthat future competitions which purport todetermine the top athlete should use bicycleswith limitations that clearly minimize advan-tages from aerodynamics (using bicycles andhelmets that emphasize safety). Developmentswould focus especially on mechanisms (ellipticalsprockets, cams, gears, etc.) and on trainingtechniques. Other open competitions could belike those IHPVA already features, where aero-dynamic innovation is given free rein. I cannotsee the viability of a middle ground whereaerodynamics is partially admitted, where the"intent" of a developer must be considered,where design rather than function is specified,where drag reduction is permitted by one meansbut not by another, where participants in thefield are coaxed into practicing or accepting"doublethink". Because I am not closely con-nected to the cycling field, I do not have ahigh regard for my own prejudices in this area.I look forward to seeing how others who are moreintimately involved handle the challenge for thenext decade: how to define, unequivocally, thelegitimate bicycle which advances cycling.

An obvious solution is to have the mostprestigious cycling competitions be ones whereequipment gives the rider no special advantage.One method is to provide identical bicycles tothe contestants, or at least require randomswitching of bicycles between contestants inmulti-race events. (Note, however, that a spe-cial liability problem is introduced if therider is not responsible for his own equipment).Another method is to emphasize an event such asa hill climb, a low-speed event where bicycledifference confer very little advantage. Themost generally applicable method would be tocertify bicycles which all have a minimum dragat racing speeds.

The minimum-drag technique could producevehicles featuring safety and economy and takethe pressure off pushing the limits of struc-ture. With a high minimum weight, high minimumrolling (tire) drag, and a minimum aerodynamicdrag (obtained any way the designer wants),speeds would be lower but records would continueto be set because of improved training.

Weight is easily determined. Total drag isdifficult but not impossible to ascertain. Tiredrag is at least rather independent of speed,and at high speed is much less than aerodynamicdrag, but can vary with tire pressure, temper-ature, and surface. Aerodynamic drag can beascertained in a meaningful way only if a"standardized rider shape" is mounted on thevehicle as the vehicle moves at the specifiedspeed, say coasting down a slope or mounted in atunnel.

I am aware of the difficulties inherent insuch calibration, and not especially optimistic

about obtaining a satisfactory resolution of thechallenge, but anything seems better than thepresent situation of permitting aerodynamicimprovements on a rather arbitrary basis. Theconcept deserves creative investigation beforerejection, and, if rejected, the alternativesmust be appreciated.

SOME OBSERVATIONS ANDCONCLUSIONS ON GOALS,RULES AND INNOVATIONS

1) Publicized competitions foster innova-tion, even where the rules inhibit major innova-tion, because there is always opportunity forsome innovation, and new/improved technology isof considerable interest to most riders andhence to manufacturers.

2) Paradoxes in the present cycling rulesabout structure vs. aerodynamics must beresolved. The legitimate racing bicycle must beclearly and permanently defined, even if thedefinition represents a significant departurefrom today's aerodynamic bicycle. Competitors,inventors, manufacturers, spectators, andofficials deserve such a clarification of what is abicycle, and of whether cycle racing is to be atest of competitors' skills or of vehicles.

3) In all sports involving equipment thereis justification for some "open" events (con-sistent with safety), no matter how many "con-strained" events there are.

4) For showing individual stamina andskill, high-speed races could be conducted onmoderately slow, very safe bicycles - heavyones with draggy aerodynamics and draggy fattires - if a standard drag specification can beagreed on and measured. It is reasonable tosuggest that some races and measurements beinitiated to explore the concept, but I doubtthat the present bicycle-race culture wouldrespond with enthusiasm. Hill climbs and therelated racing of mountain bikes over complexterrain are well accepted. Although the ridercannot establish a record applicable to otherlocations, there is the stimulus of localrecords and winning.

5) The IHPVA land-vehicle races shouldcontinue, with at least a) the open class forabsolute speed through 200m traps, and b) a longopen-category race of approximately one hour, inwhich vehicles must cope with maneuvering andwinds. IF a velodrome is available, a 4-km timetrial is also desirable, as well as a one-hourevent.

6) In order to stimulate the developmentand appreciation of practical vehicles, such ascould be used in commuting, competitions areheld at the annual IHPVA event. However thespecific definition of "practical" is not agreedupon, and in any case the judging cannot beabsolutely quantitative; speed is readily mea--i-,,A hi+ i4 rnl, nno rrnntrihiitnr n a +tr+al

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score which includes convenience, maneuverabil-ity and safety. The imperfection of rulesshould not be considered a valid reason foravoiding the practical-vehicle event.

7) In open categories, especially as exem-plified by the IHPVA races, a useful philosophyis to have rules lag technical developmentsand so not inhibit the developments. Thus,although the IHPVA rules prohibit stored energyfrom sources outside the rider, a rider might bepermitted to store energy (as in a battery) dur-ing one part of the event for use in a laterpart. Also, the vehicle could be permitted toexploit real-time wind power via a sail wing oron-board windmill. If energy storage or windaugmentation produce a race winner, great! Ifthe advantage was so large that the new tech-nique would be essential for future winners,then a new "open" category could be set uppermitting it, and another "semi-open" categorycould be devised prohibiting it, or a single dom-inant category could be selected. Innovation isserved by this attitude.

8) Technical symposia are effective atstimulating invention. They promote theexchange of ideas while establishing an enthu-siasm for new creations.

9) The standard bicycle is an elegantdesign, with admirable dynamics, simplicity, andruggedness. The touring bicycles of the year2000 or even 2050, and perhaps even the racingbicycles, will probably be rather similar to thepresent vehicles. I suspect these will continueto win out in the marketplace over recumbents oreven more divergent designs.

10) The future success of bicycles as com-muting devices will depend less on technologicalimprovements of vehicles than on social accep-tance, traffic competition, foolproof locks,effective lighting and reflectors, and helmetlaws. Safety is a dominant and ultimatelylimiting factor.

11) Auxiliary energy can assist commut-ing/touring. Just a kilogram or so of batteriescan give you the equivalent of 300 m of alti-tude, to apply as you want: accelerating afterstops or maintaining traffic speed up a hill.On a sunny day, half a square meter of solarcells can assist you with 50 watts continuouslyor can recharge a batter. A kilogram or so ofrubber bands can store the energy of a stop from10 m/s to be used in the subsequent speedup. Akilogram or so of gasoline can power the vehiclefor hours or even days. However, you have toconsider why you have a bicycle. If you reallywant a motorcycle or car, get one.

12) Formal rewards constitute a strong dri-ving force for achievement, whether the rewards

are dollars or ego-fulfillment from fame orself-satisfaction from winning. A money prizefor at technological development typically stim-ulates development efforts costing many timesthe prize amount. (The Kremer prizes forhuman-powered flight triggered two decades ofworldwide developments that probably representedan investment 30 times greater than the prizemoney.) Formal prizes provide a beneficialfocus for both inventors and competitors.

13) The preoccupation in our advanced coun-tries on technology and competition deserves alot of thought and discussion. Health, happi-ness, longevity, and appreciating and fitting inwith nature rather than modifying or destroy init - these need consideration as we work ontechnological innovation. Goals, motivation andrewards vs innovation may be imprecise subjectsfor exploration, but, in my opinion, should begiven high priority. Cycling, a positive sub-ject with few negatives, can serve as a benigncatalyst for such philosophizing.

14) Rules and categories inhibit innovationby limiting options and stimulate innovation bymotivating many riders to participate in thefield and hence encourage media interest andmanufacturers to support and develop the field.There is no one answer to the conflicts inherentin simultaneously inhibiting and stimulatinginnovation. Persons setting up demonstrations,races and records will have to accept complexityin rules and categories while striving for sim-plicity. Officials should be cautiously flex-ible. Some decisions will prove to be lesssuccessful than others; the decision makers willfind that they cannot please everyone. Theirrewards will be in knowing that they are helpingwith a sport of great value both to man thescientist/engineer and man the athlete andcreature of nature.

Paul B. MacCreadyAero Vironment, Inc.Monrovia, CA USA 91016

HUMAN POWER, Summer. 1987 vol. 6 no. 2Dage 18

HUMAN POWER, Summer, 1987 vol. 6 no. 2

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Announcement and Callfor Contributors to a

Proposed ConferenceSession at the January

1988 Annual Meeting of theTransporation Research

Board

In much of the developing world,bicycles, tricycles and carts (whetherpowered by humans or animals) playa vital role in local systems ofpersonal mobility and goodsmovement. There are substantialvariations, however, in the utilizationand mix of these modes and in howtheir use is integrated intotransportation planning and policy forurban and rural areas.

Transportation planning anddevelopment in the Third Worldsometimes serves to improveconditions for human-poweredmovement. Sometimes, however, ithas worked to restrict the use ofhuman (and animal) poweredtransportation modes. Research intothese variations and conflicts can aidour understanding of the evolution oflocal, regional and Human-PoweredVehicles and Transportation Planningin Developing Countries globaltransportation systems and the impactof these systems on economic andsocial activity. The findings of thisresearch are likely to have importantimplications for transportationplanning and policy in developingcountries, and potentially in developedcountries also.

OUTLINE OF POTENTIAL TOPICS

* Regional reports on bicycle andtricycle use in developing countries

* Developments in bicycle and otherappropriate technology

- Systems for production,distribution and maintenance ofbicycles, tricycles and carts indeveloping countries

- Designs to meet specialproblems (all-terrain bicycles, specialcarrying devices, cargo bicycles andtricycles, materials substitution)

* Conflicts between high-technology and human-powered

transportation systems* Transportation development

policies and spending priorities andtheir impact on the evolution oftransportation systems and human-powered transport.

TYPE OF CONTRIBUTIONSDESIRED

Although formal scientific paperswill be welcomed, the session'splanners will also be looking formore preliminary contributions, inthe form of talks (preferably aided byslides) that will present significantnew developments in a clear andstimulating way.

NEXT STEPS

The planning committee for thisConference Session is being co-chaired by TRB members RalphHirsch and Michael Replogle. Theyare eager to hear from researchersanywhere who have done or are doingrelevant work, and from persons whomay know of relevant recent materialpublished in developing countries.They also recognize that lack of travelfunds may represent a problem tosome potential contributors,especially those from developingcountries, and they hope to raise fundsfrom foundations and other sources toassist them. Please contact eitherone with your comments, suggestionsor inquiries:

Ralph HirschRalph B. Hirsch and

Associates3500 Race StreetPhiladelphia, PA 19104USATelephone: 215/386-1270

Michael Replogle,PresidentInstitute for Transportation

and Development PolicyP.O. Box 5595Washington, DC 20016 USATelephone: 301/495-4703 or

301/587-6137

HP Helicopter to try forHPS Prize

Mike Brace, of Reynolds & Taylor,Inc., has designed an HP helicoptercalled "Monarch", and is going to tryfor the AHS prize.

According to MACHINE DESIGN,the firm specializes in plasticfabrication, and company presidentRoger R. Reynolds thought that thehelicopter would be a great way todemonstrate the company's skills inadvanced composites. The rotordiameter is 8.5m (28 ft) and theoverall weight is just over 20 kg (45lbs). To win the prize the helicoptermust rise at least ten feet and hoverfor 60 seconds.

Media Notes

The IHPVA and HP authorAnthony F. Patroni ("A FIGURE-EIGHT DRIVE", HP 5/4) werewritten up in the Atlantic CitySUNDAY PRESS. He is the chiefslot technician at Caesar's CasinoHotel, and oversees the operation of1600 "bandits". He's also worked forthe city police department onmaintenance of their cruiser fleet.Right now, writes the paper, he'sworking on a tricycle suitable for alegless person.

Gronen Seeks to topMarkham's Record

German Vector owner WolfgangGronen reports that a high altitudespeed attempt is the works for lateSeptember/ early October.

With the support of the GermanEmbassy in La Paz, Peru andLufthansa airlines, Gronen and hisrider Gerhard Scheller will seek tobest Freddie Markham's top speed runaboard Gardner Martin's Gold Rush.

In other news, Herr Gronen reportsthat negotiations are continuing withthe intent of holding the 1988International Human Powered SpeedChampionships in West Germany.

Additional information will bepublished in HPV News.

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