Any Interest in an H-bot type Reprap?

I was wondering if anyone had done anything similar to this before. Or is there is any interest in doing something like this.
I am envisioning a Darwin/Ultimaker type machine with this type of XY movement. I would like to pursue this idea, but I don't know enough about programming to modify a Ramps Firmware to control the X and Y stepper motors in this way. Could this be a simple modification, or would a whole new firmware be needed?

H-bot U-Tube Video

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[dankimble7.blogspot.com]

... i built similar H-type cartesian mechanics with steel wires for laser-cutters some 20 years ago what was relative simple to setup - look here for some images: [forums.reprap.org]

The main advantage was the positioning of both motors (X,Y) on the base-plate, so the Y- and Z-axes had reduced mass and could be moved faster than with motors and electronics on them ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I think Forrest Higgs Sampo is similar, albeit Darwin based.

Quote
VDX
The main advantage was the positioning of both motors (X,Y) on the base-plate, so the Y- and Z-axes had reduced mass and could be moved faster than with motors and electronics on them ...

Exactly, eliminate the mass of the motors/drive train, this would translate into faster motion.

Also the single belt H-bot setup uses both X and Y motors for all moves, this could, in some situations, result in faster accel/decel times. I am not sure if this kind of "axis mixing" that is required to run a single belt setup is possible with the current hardware/firmware however.

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[dankimble7.blogspot.com]

Quote
Buback
I think Forrest Higgs Sampo is similar, albeit Darwin based.

This setup still forces one axis to carry the weight of the stepper motor and drive of the other axis. With a single belt H-bot setup, both the X and Y axis stepper motors would be stationary. The touch screen however is very cool.

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[dankimble7.blogspot.com]

There is a problem with the rail of X-axis. The force from belt is different on the ends, so you need somemething to keep it at right angle. One possibility is to make the bearing rigid enough, but that will be quite difficult in reprap budget/size.
Another possibility is to use another belt(s) that keep the ends synchronized, but this will take quite a lot of space.

Maybe better approach would be to use some usual design to move Y axis and only use H belt (or some other belt configuration) to drive X axis from frame mounted motor.