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| precision_flight_controls_inc 2009/09/08 01:10 | precision_flight_controls_inc 2009/09/08 01:14 current | ||
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| The original idea was to simply pass the old protocol over USB and add to it as needed, but it was already non-orthogonal from adding commands into whatever space was left in the structure. Too small, too limited... and with USB we were NOT running out of bandwidth. So I wrote a completely new structure with equipment classes, multi-device selectors, and a 16-bit message index. I've left more room for expansion than we'll ever need, and it has proved its worth more than once. | The original idea was to simply pass the old protocol over USB and add to it as needed, but it was already non-orthogonal from adding commands into whatever space was left in the structure. Too small, too limited... and with USB we were NOT running out of bandwidth. So I wrote a completely new structure with equipment classes, multi-device selectors, and a 16-bit message index. I've left more room for expansion than we'll ever need, and it has proved its worth more than once. | ||
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| ===== Instant Braking ===== | ===== Instant Braking ===== | ||
| - | One day the boss was visiting my office and commented about the electric trim wheel. They've been using a small, fast motor with a planetary reduction gear driving a belt, which then drives the wheel. Connected to the output shaft of the motor/gear is either an encoder or a potentiometer. One of the most vexing problems with this arrangement is that the wheel tends to overshoot; when you release the control the motor takes some time to spin down. They tried using a friction brake to slow it down, but it only slows it down. | + | One day the boss was visiting my office and commented about the electric trim wheel. They've been using a small, fast motor with a planetary reduction gear driving a belt, which then drives the wheel. Connected to the output shaft of the motor/gear is either an encoder or a potentiometer. One of the most vexing problems with this arrangement is that the wheel tends to overshoot; when you release the control the motor takes some time to spin down. They tried using a friction brake to slow it down, but it //only// slows it down, it doesn't stop it quickly enough. It also adds another component to a piece of equipment that should be dead simple, and adds sideways torque to the bearings. It's wear and tear and little else. |
| So when Mike mentioned doing something about it someday, I said, "I've got a couple ideas about that." | So when Mike mentioned doing something about it someday, I said, "I've got a couple ideas about that." | ||