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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  


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  1. R2AK 2018

    Because you cannot pedal continuously for a long distance race. You must rest. While you rest you don't move. If you can store some energy to keep moving while you are not pedaling you will cover more ground - even though your speed is lower.
  2. R2AK 2018

    We seem to be arguing different things. I say, that in theory there is an advantage to be had and I supplied some numbers to support that in post #301. Wether or not someone can implement it well enough to realize the advantage is dependent upon a huge number of variables, I can't possibly "prove" it without actually doing it. Use my example in post 301 and let me know why you don't see that there could be a (theoretical) advantage.
  3. R2AK 2018

    Yes, you are correct, I misread. We do agree that there is a hypothetical gain - which is really the only point I am trying to make.
  4. R2AK 2018

    For a flywheel system yes, but for what I am talking about (one hour run time electric) it would be pretty simple and compact. A 50 W motor/generator and 50 Watt-hours of battery capacity could be done for under 20 pounds - still against the R2AK rules. Another point, after 6 knots you can't really add more power to get more speed (on my boat), so if you pedal at 200W for an hour at a time the benefit of the energy storage system gets even better, 10.5 miles every two hours.
  5. R2AK 2018

    Apologies for beating this topic to death but I have some numbers... I loaded my R2AK design into FreeShip and ran the resistance calculations. FreeShip says to go 3 knots takes 25 Watts, 50 Watts gets 4.5 kts and 100 Watts gets 6 knots of speed. A pedaler outputting 100W could use 50 for propulsion (maintaining 4.5 kts), and 50W to charge something - lets assume 50% losses and we will have 25 Watts to use while the pedaler is resting, maintaining 3 knots of speed while depleting the stored energy. That would be 6 miles covered in two hours with a straight pedal drive, or 7.5 miles covered using the energy storage system taking into account 50% losses.
  6. R2AK 2018

    In two hours the 3 knot boat goes 6 miles, a 2 mile gain every hour. Yes, there are a lot of assumptions made in order to explain the concept. 50 watts over a one hour period is not large amount of energy, your laptop batteries may store more energy than that. It should obvious that a real world scenario is going to be different. Probably not worth it, but maybe if you are doing the race solo in a strictly human powered boat you could use such a device to your advantage - which is a good reason why it would not be allowed per the "spirit" of the race. I'll remind you that I replied to the comment "The idea isn't likely to affect race results at all, is it?", that a stored energy system would not give an advantage. I have provided a hypothetical example of how it could provide an advantage. Not trying to convince anyone to try it...
  7. R2AK 2018

    I'm prepared to abandon too. To be clear, my rough example does not take into account conversion losses - which would be significant but I don't think it would entirely negate the advantage. Assume a pedaler can sustain 100 Watts output for an hour at a time, then they need a one hour break. Either that 100 Watts all goes into propelling the boat at 4 knots or half goes into propelling the boat at 3 knots and half goes into some form of energy storage. While the pedaler rests the energy storage system is used and continues to propel the boat at 3 knots. Over a 24 hour period the 3 knot boat will have gone 24 miles further than the 4 knot one.
  8. R2AK 2018

    ??? The advantage would be that you could make 3 kts 100% of the time vs 4 kts 50% of the time. 72 miles per day vs 48 miles per day for the same amount of energy input.
  9. R2AK 2018

    Speed does not linearly increase with power input. As a rough example, 50W may get you up to 3 kts while 100W only gets you up to 4 kts.
  10. R2AK 2018

    I think it could affect race results, even for a solo team. If half the time you put in 100 Watts to the system, 50 to propulsion and 50 to storage, then when you are not pedaling you draw off the 50 that went to storage you will make better time than if you put 100 Watts into propulsion then took a break for an equal amount of time.
  11. R2AK 2018

    That is the purpose of Rule 8 - to cover those things that are not in black and white. No, a flywheel is not a motor, it is an energy storage device. Using a flywheel to smooth out power pulses is very different than using one to store energy so that it can move your vessel while your legs take a break. Personally, I wouldn't care but I don't believe the judges would approve it.
  12. R2AK 2018

    They don't specifically rule out energy storage devices but they do say you can't charge a battery to use for propulsion. I'm confident that Rule 8 will determine that you also cannot "charge" a flywheel.
  13. R2AK 2018

    If the power is there, then you can make the torque via gearing. Seems to me that recumbent spinning is okay for power, but being able to stand on the pedals is better for power (and torque). A couple of common misconceptions that are passed around as wisdom; It's not the HP that matters but the torque. It's the current that kills you, not the voltage. In both examples the former cannot exist without the latter, but without the former, the latter is useless.
  14. R2AK 2018

    Copied from the rules: Every team must have a vessel without a motor. No motors onboard, at all, even if they’re not hooked up, disabled, etc. This includes motors and engines of any fuel type — and that includes fossil fuel powered generators. Human and wind power only for propulsion. Solar, wind and human are ok for charging things —and no, not for charging a battery that powers propulsion of any kind. Bilge pumps are ok, unless it’s really big and pointed aft (see Rule 8)
  15. R2AK 2018

    About using belts, you can contact Dan Parsons at Gates 303 744-5800 (ptpasupport@gates.com) and he can give recommendations on the best belts for your particular application. I can tell you that he does NOT recommend the carbon series for boat pedal drives. My particular design used a two stage reduction: a 25 mm 5M belt for the first stage (6.667:1) then a long 15 mm 5M belt with a half twist down to an 18 tooth sprocket on the prop shaft for the 1.5:1 final drive.