Quote:
Originally Posted by AdamHeard
For a system such as this, you really need to model and do the math for YOUR system.
The lever arms vary from team to team, the CG location varies, etc... For everything. To say team X had a ratio of 50:1 so we can use that is not going to work.
You need to look at your rotating joint, and figure out what torque the CG is causign around that. That number will vary throughout the rotation. For conservative gearing, through gearing have that equal 20% of the stall torque, that assures it'll be moving. If you gear it near stall, you'll just sit and pop breakers.
|
Very much agreed.
For example, we asked around a lot before plunging into design. We asked, IIRC, 33, 148, 254, and 1114, all of which use a wildly large range of reductions. The important part of asking around though, was understanding the underlying concepts involved between the different designs. IIRC, 33 had a fairly small arm they were rotating about, so they were able to use 1 CIM and hang fast. 254 was like us, using a PTO, because they had a much larger arm to rotate about, and so to hang in a short amount of time needed much more power. (Don't take my word for their systems. If you're curious, ask the teams who made them. This is my interpretation of their explanations) Using the information they gave us, we were able to determine what kind of ratios we needed to hang in the time we felt reasonable.