Add pedals?

[chrs]

An interesting comparison: The Cd*A product for the insight is about the same as for a bicyclist. The Insight is bigger, but it's better shaped. (For aerodynamics--bicyclists tend to be nicely shaped too, but in a different sense.) That makes it tempting to think that one could add pedals to the insight and be able to cruise at low speed on pedal power alone. But it's so much heavier than a bike that the rolling resistance force is much higher, even if the rolling resistance coefficient is similar.

So here are some numbers, just for fun:

Moderate biking at 15 mph--a pace that someone in moderately good shape can maintain for a while-- takes 100 W.
Fast biking--a sprint for the same 15 mph rider--takes 200 W.
Super-athletic biking at 30 mph takes 600 W.

So here's what that means in the insight:
100 W gets you 5 mph. Pretty slow but faster than walking for the same energy input!
200 W--one person working very hard, or two at a moderate pace--gets you 9 mph.
400 W--two people working like crazy--gets you up to 16 mph.
600 W--one Lance Armstrong--gets you 20 mph.
And 1200 W (two Armstrongs) gets you up to 30 mph.

You could also use it for assist--sort of an ultra manual version of MIMA. Can't quite maintain speed in lean burn? Start pedaling! But as you get to higher speeds, the amount you can help gets less and less important--at 40 mph, 200 W of pedal power only gets you 1.7 mph extra; at 60 mph, less than 1 mph extra. Still, that's at least as good as some of the mods I've seen discussed here.

And here's where it might actually be useful: You're in autostop, and you want to creep forward a car length--just pedal! Or you are rolling in autostop (or forced autostop), and could almost roll to an upcoming stop sign or downhill or whatever, but aren't quite going to make it. With pedals you could roll a little further, or go 5 mph faster, which sometimes would be just enough to avoid turning on the engine.

Ever notice how much the mpg reading drops during parking lot manuvering? Pedals could be used for pulling in and out of the parking space. Now I'm starting to convince myself that this is actually a good idea. Also, it would be nice to get some exercise while biking.

The extreme of this type of vehicle is a "Twike" (http://www.twike.com/). Super light electric/human hybrid, said the get the equivalent of over 500 mpg. Not legal in the US, apparently.

Charlie

[Mike Dabrowski 2000]

Chrs
Why not cut some holes in the floor and just use your feet, It may be easier than trying to set up pedals, as it is a little cramped under that steering wheel. :twisted:
Along those same lines, I was thinking that adding my windsurfer rig to the rear window area could make it a three power source hybrid, gas battery and wind. I had my iceboat up to 65mph with that set up.(lake was pretty flat, no hills)

[commuter]

Just this morning I was coming over a freeway over pass and was in Auto Stop mode, all most had to come to a complete stop, but just started to move right before the complete loss of momentum. I was thinking of sticking my leg out the door to push the Insight like a scooter, except I need all of my extremities for other things in life. Maybe the pedal idea would have come in handy in that situation.

[Dougie]

This might work if you could eliminate the rolling friction drag, which is more or less constant with speed. You would have to use bicycle tires and no transmission gears...

[chrs]

Actually, from what I've been able to gather, the OEM insight tires have a very similar rolling resistance coefficient to bike tires--about 0.5% (meaning the drag force is 0.005 times the normal force). The reason there's more rolling resistance in an Insight vs. a bike is just that the normal force is 10 X larger. Apparently the square-cross-section steel-belted radial design provides enough advantage to make up for the thicker rubber. But the square cross section wouldn't work for cornering on a bike.

Charlie

[highwater]

Along those same lines, I was thinking that adding my windsurfer rig to the rear window area could make it a three power source hybrid, gas battery and wind.

I had invisioned a transparent sail of sorts, attached between the interior and the rear hatch, such that it would catch the wind when the hatch was open.
Would need some vacume assist for actuation (open/close)

Sorry moderators; this has nothing to do with pedals

[Insightful Trekker]

Originally Posted by chrs

<snip>

And 1200 W (two Armstrongs) gets you up to 30 mph.

<snip>

I'll take 4 "Lance Armstrongs" to go please. :P

But will "they" be "pickey" eaters and how much "fuel" will it take to keep them going ($)

[Mike Dabrowski 2000]

I was in my Insight this afternoon, and with the seat all the way back, You could probably have pedals. Sorry for doubting Chrs, it is possible.

So you could pedal around mall parking lots, and in stop and go traffic, and then flip the pedals out of the way to use the gas/electric. Is there a way to compute how fast you could push the 1800 lbs up a small grade with moderate pedaling, as there will always be hills of one magnitude or another.
At least in New Engand.

[chrs]

Up a hill? No problem. On a 5% grade, 200 W gets you almost 1 mph. Assuming you have a very low gear for the pedals, it will only take three times as long as walking to the top of the hill.

Charlie

[nemystic]

One of my many "other" vehicles is a "real hybrid" recumbent bicycle, used mostly for commuting and short distance errands. On my 45 mile RT commute, it operates about 85% on human power, but is capable of operating on electric, human, or combined power, and therefore meets this new, arbitrary (IMO) hybrid definition.
As the electric motor is 600W at maximum output, and considering my age, maximum reasonable human output is down to about 400W or less , I can offer empirical confirmation of your analytical conclusions, Charlie. Thanks for the extensive work to provide this really interesting data!

Before seeing the previous 2 messages in this thread, I'd planned to qualify the proposed concept as being highly terrain dependant for a 2000 lb vehicle! In New England and other areas, terrain is a major consideration.

So, while I believe your idea is truly innovative, and while I'll admit to wishing for pedals in the Insight, many times in stop and go gridlock traffic (on level terrain, of course), my thinking is that this "Flintstones" concept may not be practical for relatively heavy vehicles - including the Insight, at least in New England.

However, I also believe that it's time that light weight vehicles, such as the Twike, be accomodated with infrastructure, tax incentives, and general public acceptance, as a reasonable alternative to heavy transportation vehicles that depend on the "fossil fuel fairy".

-Brian