MattyCiii
100 kW
OK, the name is a little queer. "Velobration" is a portmanteau of "velomobile" and "collaboration". It's the name I'm using for now to label an effort by 900steve and I to build a common platform we each can use as a foundation for our respective next builds.
The Concept: Design and build a mid drive "box" optimized for the purpose: to be an excellent electric/human power plant. Once built, build a bike around it. It will physically bounded as follows: It will be aft of the top tube and the down tube. It will be below the seat. The rear wheel will be suspended. The common power module will be what the rear suspension pivot and shock mate with. Look at this thread to get a mental picture...
--- I look at the GNG drive, or Stokemonkey, or the latest generation European mid drives like the Bosh system, and what I see is a design philosophy of Start with a bike, then modify it....
Bullshit! I say, start with a drive system, and then figure out how to build a bike around it.
Outline: Steve and I have a common baseline. The sum total of his and my electric bike experience are riding my bikes - insanely responsive RC drives, NuVinci pedal power for smooth shifting human input, etc. After lots of scratch drawings in CAD and on graph paper, we decided there's merit to building a common power module that houses the following:
1. Human powered pedal cranks, and possibly use an ATS or Schlumpf drive for greater gear range,
2. RC motor and reduction. Look at my Dahon Folding Bike. Motor and reduction are pretty close to the center of the bike which is nice. Center the mass, it's good for snappy performance.
3. Combine power centrally, using a jack shaft. Consistent with one of the fundamental constraints of my third bike build (keep weight and complexity away from the wheels), we'll combine motor and pedal power in the common power module by way of a jackshaft.
--- Moreover, we've decided to use a NuVinci N360 as the jackshaft, and to use the axle of that NuVinci as the pivot point for the rear shock. This ties up a lot of little issues into a neat little package. But this creates a design-packaging nightmare and requires lots of thought, and more than a few custom parts. But that is what engineering is all about - compromise, and finding solutions.
We've started the design/build of this common power module (CPM). Once we've worked the bugs out there will be multiple CPMs - Between Steve and I we'll build at least 4, maybe more depending on economies of scale (for example if we outsource anything to Big Blue Saw, they have a giant price break when ordering 5x versus ordering 4x...). Steve and I will start posting comments and pix to illustrate the build. Then as we go from the common foundation to full bike build, we'll each have our own design goals and needs, and likely have radically different complete bikes (for example I want my bike to be a folder but that's not necessarily high on Steve's list.
Stay tuned, this is going to be interesting...
The Concept: Design and build a mid drive "box" optimized for the purpose: to be an excellent electric/human power plant. Once built, build a bike around it. It will physically bounded as follows: It will be aft of the top tube and the down tube. It will be below the seat. The rear wheel will be suspended. The common power module will be what the rear suspension pivot and shock mate with. Look at this thread to get a mental picture...
--- I look at the GNG drive, or Stokemonkey, or the latest generation European mid drives like the Bosh system, and what I see is a design philosophy of Start with a bike, then modify it....
Bullshit! I say, start with a drive system, and then figure out how to build a bike around it.
Outline: Steve and I have a common baseline. The sum total of his and my electric bike experience are riding my bikes - insanely responsive RC drives, NuVinci pedal power for smooth shifting human input, etc. After lots of scratch drawings in CAD and on graph paper, we decided there's merit to building a common power module that houses the following:
1. Human powered pedal cranks, and possibly use an ATS or Schlumpf drive for greater gear range,
2. RC motor and reduction. Look at my Dahon Folding Bike. Motor and reduction are pretty close to the center of the bike which is nice. Center the mass, it's good for snappy performance.
3. Combine power centrally, using a jack shaft. Consistent with one of the fundamental constraints of my third bike build (keep weight and complexity away from the wheels), we'll combine motor and pedal power in the common power module by way of a jackshaft.
--- Moreover, we've decided to use a NuVinci N360 as the jackshaft, and to use the axle of that NuVinci as the pivot point for the rear shock. This ties up a lot of little issues into a neat little package. But this creates a design-packaging nightmare and requires lots of thought, and more than a few custom parts. But that is what engineering is all about - compromise, and finding solutions.
We've started the design/build of this common power module (CPM). Once we've worked the bugs out there will be multiple CPMs - Between Steve and I we'll build at least 4, maybe more depending on economies of scale (for example if we outsource anything to Big Blue Saw, they have a giant price break when ordering 5x versus ordering 4x...). Steve and I will start posting comments and pix to illustrate the build. Then as we go from the common foundation to full bike build, we'll each have our own design goals and needs, and likely have radically different complete bikes (for example I want my bike to be a folder but that's not necessarily high on Steve's list.
Stay tuned, this is going to be interesting...