Fin Control Definition

Click the Fin Control Definition tab. The screen is as follows. The inputs do not need to be updated. These are the same inputs that were used in the Contraj Tutorial.

There are 6 different input columns used to define Fin Control events. The columns are as follows:

EventId - Allows the user to set the output label of the control events within the simulation. The EventID is an integer.

On_Off - Allows the user to turn the control event On (1) or Off (0) for the simulation run.

StartTime - Allows the user to input the time of each control event to start.

FinSetID - Allows the user to designate which finset the control event will affect. Currently only one finset can be controlled at one time.

RollAngle - Allows the user to set the angular orientation for the force application to be applied towards the projectile body. The coordinate system is such that

0 = Force will be applied to the bottom of the projectile
180 = Force will be applied to the top of projectile
90 = Force will be applied to the left side of projectile
270 = Force will be applied to the right side of projectile.

CtrlOpt - Allows the user to choose from four Flight Control Options which work in conjunction with the roll angle chosen in the previous column. The value is an integer from 0 to 3.

0 - No Control
1 - Fixed Control Angle - This control option applies the force generated only at the roll angle orientation chosen by the user regardless of the presence of spin or no spin.
2 - Fixed Roll Angle until Roll Constant - This control option starts the control event at the Roll Angle and Time input by the user however; this option takes into account the spin rate of the projectile also and applies the force vector over the range of roll angles the projectile experiences during the time of the control maneuver. For example, the user inputs 90 deg as the roll angle and the projectile is spinning at 0.5 cycles per second with a 1-second-long control event. Therefore, the simulation would start applying the force at a Roll Angle of 90 Degrees but as the projectile spins for the time of the control event the roll angle of the force vector would change 18 degrees per 0.1 second TOF until the end of the control event.
3 - Body Fixed - This control option applies the force vector at the Roll Angle within the Body Fixed reference frame at the time of the control event. However; if the projectile is spinning the Roll Angle could be at any orientation within the Earth fixed reference frame. As with option 2 the roll angle of the force vector will rotate with the spin rate.