This vehicle is an interesting way to transport up to 4 people in a slightly awkward (2 backwards facing) way, if it is legal in your jurisdiction. Also - do not expect to go 60 MPH for long, not just because you can't create the power to sustain that speed, but also because you are sitting in not much more than a go-kart: no protectoin from wind and at 60 MPH you would be surprised how uncomfortable that gets real quick. Another thing is that this is an ultra-light vehicle with moped wheels, so I am concerned about the safety of doing 60 on those tires. My e-Bike has pretty sturdy 1.95" tires on a solid rim and a *very* ridgid frame, but when I did a fast decent and approached about 40-45 MPH, I was not comfortable going any faster. Since that was also the posted max speed, no cars needed to go any faster or indeed dared to pass me on the way down. This car, where you are essentially sitting in a skiff on wheels with no protection, is comparable to a bicycle on 4 wheels (which is probably how it will be seen legally and if necessary, registered as such) The winnd resistance alone will likely be comparable to a bicycle for each passenger, so even if there are 4 in the car, the sustained speed will likely be bicycling speed (around 15 MPH if you are doing well) and only using the battery for hill climbing and acceleration. Interesting idea but since there is the same weather protection as on a bicycle (none), why not simply ride an e-Bike?
Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of Chris Tromley via EV Sent: Sunday, July 06, 2014 7:46 AM To: Peri Hartman; Electric Vehicle Discussion List Subject: Re: [EVDL] Man power EV On Sat, Jul 5, 2014 at 6:35 PM, Peri Hartman via EV <[email protected]> wrote: > Really, as creative as it is, can it be more effective than a bicycle > mechanism? You'd be surprised. Any crank mechanism is rather limited in efficiency. At the top and bottom of the stroke it doesn't matter how hard you push - all the force goes into compressing/stretching the crank components (minimally) and none goes into moving the vehicle. You only get full efficiency at 90°. (What's the area under a sine curve, 60-some percent of a constant function? That's about the best you can hope for with linear input force.) Yes, a cyclist can apply rotary forces to the crank, and experienced cyclists do, but the human body just isn't kinesthesiologically configured to do this well. The leverage is all wrong. A rower gets much better efficiency in terms of the mechanism that puts power into motion, but that has its limitations too. (For example, it's one-way only.) Years ago I did preliminary development on an HPV to compete for the duPont prize (http://www.ihpva.org/land.htm) that ditched the traditional crank mechanism, and should be better than a rower. But then I detoured and went to college instead. That concept might make a killer recumbent bike. I've always wanted to follow through on that. Maybe in retirement.... Chris -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140706/4c8b2613/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
