30 lines
739 B
JavaScript
30 lines
739 B
JavaScript
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'use strict';
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const RPM = 15;
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const RPS = RPM / 60; //Rotations per second, from 15RPM
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const D = 31.27; //mm, Diameter of core (daylight spool here) 32, or 31.5
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const THICKNESS = 0.11938; //mm, 16mm = 0.0047in thick
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const PITCH = 7.6;
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class Roll {
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constructor () {
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//var D_END = 87.16;
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this.TOTAL = 33 * 1000;
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}
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//R = √(36000 × 0.005/π + 32) = √(57.30 + 9) = 8.14 inches.
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diameter (length = 0) {
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const val = ((length * THICKNESS) / Math.PI) + Math.pow(D / 2, 2);
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const r = Math.sqrt(val);
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return 2 * r;
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}
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length (d = 0) {
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const len = Math.PI * (Math.pow(d / 2, 2) - Math.pow(D / 2, 2));
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return len / THICKNESS;
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}
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//mm/s
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speed (d = 0) {
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const mm = d * Math.PI;
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return mm * RPS;
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}
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}
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module.exports = Roll;
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