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bit more comment cleanup

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This commit is contained in:
JoePfeiffer 2020-07-07 10:52:32 -06:00
parent 224e0ea3fd
commit e1f59d7dc8
1 changed files with 9 additions and 7 deletions
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16
core/src/net/sf/openrocket/rocketcomponent/FinSet.java
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@ -638,17 +638,18 @@ public abstract class FinSet extends ExternalComponent implements RingInstanceab
} }
/* /*
* Return an approximation of the longitudinal unitary inertia of the fin set. * Return an approximation of the longitudinal unitary moment of inertia
*
* The process is the following: * The process is the following:
* *
* 1. Approximate the fin with a rectangular fin * 1. Approximate a fin with a rectangular fin
* *
* 2. The unitary moment of inertia of one fin is taken as the average * 2. The unitary moment of inertia of one fin is taken as the average
* of the unitary moments of inertia through its center perpendicular * of the unitary moments of inertia through its center perpendicular
* to the plane (Izz/M), and through its center parallel to the plane (Iyy/M) * to the plane (Izz/M), and through its center parallel to the plane (Iyy/M)
* *
* 3. If there are multiple fins, the inertia is shifted to the center of the * 3. If there are multiple fins, the inertia is shifted to the center of the
* Finset. * FinSet.
*/ */
@Override @Override
public double getLongitudinalUnitInertia() { public double getLongitudinalUnitInertia() {
@ -679,9 +680,10 @@ public abstract class FinSet extends ExternalComponent implements RingInstanceab
if (finCount == 1) if (finCount == 1)
return inertia; return inertia;
// recheck (yet again) when I get home. Need to apply parallel axis theorem // Move axis to center of FinSet. We need to apply parallel axis theorem
// to Izz, but not to Iyy. Since we're looking at average of Iyy and Izz, // to Izz, but not to Iyy (as the displacement as we move to the new axis
// weight parallel axis theorem by 1/2. // is along Y). Since our moment of inertial is the average of Iyy and Izz,
// this is accomplished by just weighting the transformation from the theorem by 1/2
return inertia + MathUtil.pow2(MathUtil.safeSqrt(h2) / 2 + getBodyRadius()) / 2; return inertia + MathUtil.pow2(MathUtil.safeSqrt(h2) / 2 + getBodyRadius()) / 2;
} }
@ -695,7 +697,7 @@ public abstract class FinSet extends ExternalComponent implements RingInstanceab
* about the center of the approximated fin. * about the center of the approximated fin.
* *
* 2. If there are multiple fins, shift the inertia axis to the center * 2. If there are multiple fins, shift the inertia axis to the center
* of the Finset * of the Finset.
*/ */
@Override @Override
public double getRotationalUnitInertia() { public double getRotationalUnitInertia() {