I'm building a retractable canopy to provide some shade over our swimming pool in the summer. The canopy is about 24 feet wide by 40 feet long. When retracted, it will be wound up around a "spool" which is a 25-foot long, 5-inch diameter stainless-steel pipe. I intend to have a motor rotate the spool to unwind and wind up the canopy at one end, and a similar spool and motor at the other end to wind and unwind the cables attached to the edge of the canopy:
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This all sounds good in theory, but, being a novice at this sort of thing, I'm wrestling with some elementary details that have me stalled. The canopy needs to have 200 pounds or so of tension on it to keep it from sagging excessively, and what I haven't figured out is how to
A) maintain the proper tension when the canopy is extended B) as part of A, to lock the motors so the canopy doesn't move when they are turned off C) decide what kind, size, torque, horsepower motors to use D) whether to drive the spools directly via coupling, or use a chain with some gear ratio E) related to D, what RPM to use F) do all this with a modest budget (no $5000 control systems!)
Can anyone offer some suggestions (in simple terms for the neophyte) for how to make this work?