Pedal Electric Hybrids?

[jawnn]

Howdy thar folks.

I am very interested in pedal electric hybrid vehicles. I want to build a velomobile eventually.

If any one has any info about the concept. please let me know.

At first I thought I would just have to use an electric motor and batterers like every one else...because I was once told this concept would not work.

Actualy it does look like he has batteries under the seat.?

But then I saw the thread here called "Pedal/Electric Hybrid, great youtube find, I want one."

Unfortunately there is no link to more info from the video.

[jawnn]

I was thinking that I realy need to learn more about how motors work and how to generate electicity with pedal power.


Can any one name some books for me to read?

[mackerel]

A neighbor of mine has an electric bike, which he can peddle when the battery dies before he gets where he's going. The battery is about half the size of a moderate shoe box, and there's a motor assembly at the hub. The bike is heavy, but most of the time that's no big deal because he isn't peddling.

To do this, you need to add a generator and charge controller to his set up, plus the fairing. It gets complicated because you want to peddle for charging, and for direct mechanical drive propulsion, which means carrying some kind of mechanism for switching between the two, which will add weight. If you peddle for electricity for the motor in real time, you have to put up with the efficiency losses of the motor and generator, although it will be a simpler design.

A third option is to have a stationary generator bike that the velo plugs into. When out and about, you either go battery or mechanical direct drive. When home, you charge the battery from the stationary plant.

I've always wanted a good velomobile...

[govman6159]

I have a lot of experience with ebikes and I know quite a bit about velos. The biggest drawback to a velo is safety. Velo's ride so low, they are not safe to drive on the road. Additionally, they can't ride in a bike lane b/c they are too wide. This extremely limits their usefulness. Velo's require less energy (than a regular bike) to maintain speeds above 12mph but require more energy to get to 12mph (since they are heavier). They also require more energy to climb a hill (due to weight).

In order to best assist you, I need to know more about your goals.

1) What is the intended use of the vehicle?
2) Do you live in a high traffic area?

I would be happy to answer any questions for you but I want to make sure we start out on the same page.

[jawnn]

I have already done research about the velomobile I would build, it ended up being about 550lbs to get any mileage with lead acid batteries.

If finally decided that I would need to build it as motor cycle trike just to make it legal. Not that it would be easy to build a motorcycle that light weight without some bicycle parts.

But I didn't think enough about pedaling for electricity only because people have insisted that it is too inefficient. But it looks like it can work.

So the only reason to build one would be to avoid hard pedaling up steep hills.

I would like to see one that does not have to carry big batteries. Well the new lithium polymer batteries look like they hold much more power than anything else. Maybe by the time I have enough money, battery technology will be even lighter weight.

Does anyone know if I could build a trike with bicycle wheels in the front and a light weight motorcycle drive wheel (Mostly because of the brakes) and get it legalized?

[mackerel]

The answer varies from state to state.

[govman6159]

Really, what is your goal? Are you just wanting to avoid hard pedaling going up hills? If so, why don't you just build a bike like this (see attachment)? I built this for less than $600. It has lithium batteries and it elimates the need to pedal at all (if you don't want to).

If you're interested, here's the specs:

Batt pack: 16 Headway 40152S cells (24V/30ah)
Top speed: 25mph (flat surface)
All electric range: 20-25 miles (terrain dependent)

The mid mount motor allows me to still shift gears so I can use the motor's pwr in the most efficient manner for the terrain.

You're project sounds very ambitious to me but, I don't want to be a stumbling block. Anything is possible if you have the money and the time. I would hate to see you do it with SLA's. They are just too heavy and bulky (not to mention their service life).

If you need more info, let me know.

[jawnn]

Ultimately I want to avoid carrying large batterers Like bypass the batterers?

what kind of motor could do anything at 165w?

Maybe use the electricity just for high toque hill climbing, but how can I have both with out a lot of gears...???? (slow pedaling drive train on the hills, AND a higher speed generator.)

I need to learn how to program ac motors, any books?

[govman6159]

The short answer is, you can't. If you want speed, you will need higher gears. If you want to climb hills, you will need low gears. If you've ever ridden a one speed bicycle, that will give you a basic idea of the need for more gears.

165W motor could do a lot if you are at speed (above 12mph) on a level surface but (some velos only need 80W's to maintain 12mph (level surface)), climb even a slight upgrade or take off from a dead start and 165W is virtually useless (even for assist). This is especially true for a 500+ lb vehicle. With a vehicle that size/weight, I would recommend at least 2.5hp or 2000W (for assist with gearing).

As for programming AC motors, this is done by motor controllers. The more poles the motor has, the more it can be controlled but even then it is only done by halving the AC frequency. For instance, a 2 pole motor with a 115vac 60hz input will have an rpm of about 3600 (minus losses), a 4 pole could have 2 speeds (1800 or 3600) an 8 pole could have 3 speeds (900, 1800 or 3600). This limitation would necessitate gearing. This is why DC motors are typically used for transpo.