Difference between revisions of "Motors"
From WhimWiki A Wheelchair That Makes Sense
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**Could try to replicate the current electro-magnet option, but from what standard parts? | **Could try to replicate the current electro-magnet option, but from what standard parts? | ||
*Clutch to allow for manual operation of the chair | *Clutch to allow for manual operation of the chair | ||
| + | |||
| + | ==Motor Questions== | ||
| + | *Which type of motor | ||
| + | **"Standard" 12 or 24v motor | ||
| + | ***+Lower RPM, so not as much gearing | ||
| + | ***-More expensive ($500+ from most sources) | ||
| + | ***+Power closer to what we're used to supplying (24VDC, 6A) | ||
| + | ***-Low horsepower (0.2HP) | ||
| + | **Treadmill motor | ||
| + | ***+Cheap (less than $50 on EBay) | ||
| + | ***?High RPMs | ||
| + | ****Possibly lowered enough via power management | ||
| + | ***-High voltage (~120VDC) and Amperage (20A) | ||
| + | ****Need to play with this using smaller values, to see how it performs, and what the current draw is like | ||
| + | ***+Much higher horsepower (~2.5HP) | ||
| + | **For either motor type, can the output shaft support the weight of the chair | ||
| + | ***Or do we need to use a pulley (or chair, or direct gear, or...) to drive the wheels | ||
| + | *How do we stop this thing without requiring a constant power drain? | ||
| + | **Imagine, looking down a hill in San Francisco, with a low battery, needing to get home... | ||
| + | *Then, how do we release that brake manually so the chair can be moved without battery power? | ||
| + | **Now, can we make it so that the driver can control the clutch while seated in the chair? | ||
=Assumptions= | =Assumptions= | ||
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*Drive wheels using standard bicycle sizes | *Drive wheels using standard bicycle sizes | ||
**26" = 81.68" circumference (depending on tire?) | **26" = 81.68" circumference (depending on tire?) | ||
| + | ***Very common | ||
***Probably too big | ***Probably too big | ||
**24" = 75.40" circumference ... | **24" = 75.40" circumference ... | ||
**20" = 62.83" c... (BMX bike wheel) | **20" = 62.83" c... (BMX bike wheel) | ||
***Very common | ***Very common | ||
| − | *** | + | ***Often used for heavy-duty riding (tricks/stunts) |
| + | ****Are they more durable? | ||
*Two motors (1 per side) | *Two motors (1 per side) | ||
**An alternative would be four-wheel drive, using Mecanum [[wheels]] | **An alternative would be four-wheel drive, using Mecanum [[wheels]] | ||
