MOEPED 6 Update: 3 to 1 ultracapacitor bank
DGo...@replikon.net
Educational Demonstrator) human/electric hybrid bicycle series go back
to 1999-05-05 in the Google Groups archive:
http://groups.google.com/groups?q=moeped&start=170&sa=N&scoring=d&hl=en&ie=UTF-8&
The vehicles entertain and educate bicycle riders, alternative-energy
politcal activists, physicists, and my fellow students at NVCC as I
ride and show them on local trails, Metrobuses, and on the Metrorail.
Version 6 combines a Lightning Cycle Dynamics (make) Thunderbolt
(model) S/M frame size recumbent bicycle with 3 ultracapacitor packs,
a small NiCd battery, and the EV Wilderness 600 watt rated, 36 VDC /
15 A front hub motor in a 20 inch wheel to provide two-wheel drive,
auxilary power to a PDA/phone and loudspeaker, and an "electric
flywheel".
The "flywheel" uses the voltage constant of the motor damped by about
2 ohms ESR (Effective Series Resistance) to make an analogy between an
equivalent mechanical flywheel with kinetic energy quadratic in speed
and the ultracapacitor bank with electrical energ quadratic in
voltage. To be honest, my gut feeling is that mass for on-board mass,
the two are nearly equivalent in performance. I've never tried such a
large mass flywheel on a bicycle.
A transmission of some kind is needed to use a mechanical flyweel, and
such a transmission for a bicycle might weigh 5 pounds, but I find
that a carefully wired 4PDT switch provides the operator with suitable
choices for storing and using electrical energy at much less mass, so
I've been riding and using the bicycle and the capacitors wired in
series / parallel for about two weeks now. It's exciting; you can flip
the switch and really feel something happen.
NASA has an ultracapacitor bicycle with 7 speeds and switch-mode power
conversion, and I hope to speak with the principle invesigator soon.
We've had a couple of emails back and forth. NASA has published a
report on tests of their ultracapacitor bicycle.
Within two weeks I should have a more reliable NiCd pack with a
converter to 3, 6, 9, or 12 VDC built in. Then, the loudspeaker and
PDA/phone will be powered by the drive system, increasing the range of
operation to a "century ride", 100 miles or kilometers.
Around October 10, the PHY 298 class under Dr. Walerian Majewski
starts at NVCC-Anndandale, and I encourage any interested residents of
or visitors to the Northern Virgina or Washington, DC area to contact
me for a "tour" of the MOEPED 6 this fall.
Doug Goncz
Experimental Machinist
Replikon Research
Seven Corners, VA 22044-0394
DGo...@replikon.net
the WHIRL list (Washinton's Highly Independent Recumbent Lovers). You
may repost, quote, or forward this notice wtihout limitation.
Actually, I'd really appreciate it if you did.
PHY 298 at NVCC started Friday, October 24, 2008, with 11 students. At
least 2 are registered already. Late registration is open until
October 31. We meet 8 times before the semester ends in December. We
do not meet Friday, 7 November, 2008.Dr. Majewski reported the Society
of Physics Students chapter at NVCC is highly regarded and competes
with university chapters. IIRC, there is no other SPS CoCo chapter at
all. I joined the Society Friday night.
The class project is to build a demonstrator Inductrak maglev track
and train and measure what we can, whether "liftott" is acheived or
not. Inductrak uses a Halbach array facing a passive coil track and
was developed at Livermore. No superconductors are needed for this.
Dr. Majewski offered me the chance to sustitute the MOEPED for the
Inductrak, so I renewed my efforts and repaired the lead wires on the
damaged hub motor by installing 8 long screws to guide the shell
halves apart, and then together after the lead repair wihthout damage.
On reassembly the halves came together with a loud snap but the motor
works, so I will take this offer.
I rode the repaired system yesterday and twice made charging runs on
the flats followed by lively electric power sprints. I did not use the
small NiCd battery at all. I charged again approaching Shirlington and
ascended the pedestrain ramp crossing Interstate highway 395 under
power. It was a fine, clear day. I am delighted. All the components
seem the right size.
The NOAA forecast for Friday is 66 deg F and sunny. If there is no
rain this Friday, I will present what I know and what I think, outline
a plan for the semester, and show the MOEPED to the students and any
of you Dear Readers who appear this Friday, October 31, 2008, between
4 and 6 PM in CF 213, on the top floor of the Food (Cafeteria) buildng
at NVCC, 8333 Little River Turnpike, Annandale, VA 22003. By charging
the system from the battery, some low-power demonstrations may be made
indoors. I'll probably ride down the Dora Kelly train to King Street
and take the Metrobus 29K to NVCC, then return home by the 29K and the
28 bus.
The dashboard requires redesign to accomodate human factors and I
regret I cannot offer anyone a ride this Friday. It's just too
susceptible to operator errors. Sorry.... I am working on a new
dashboard.
Safety first!
Selective quote:
On Oct 5, 7:28 am, DGo...@replikon.net wrote:
> Usenet discussions of theMOEPED((MObile Experimental Physics
> Educational Demonstrator) human/electric hybrid bicycle series go back
> to 1999-05-05 in the Google Groups archive:
>
> http://groups.google.com/groups?q=moeped&start=170&sa=N&scoring=d&hl=...