Lateral Movement#

block

Block appearance in REPEAT VISION#

  When dividing complex movement of missiles into longitudinal and lateral, it is assumed that in the first approximation the longitudinal movement does not depend on lateral one. Thus, only those forces and moments that operate in the firing plane are taken into account in the equations for determining the characteristics of longitudinal movement. When determining the characteristics of the lateral movement of a missile, it cannot be considered independent of the longitudinal one, therefore, all forces and moments, which in some degree can cause the missile to deviate from the firing plane, are included in the equations.

  System of equations describing lateral motion of rocket center of mass in half-speed coordinate system 0XYZ (1), (2), (3), (4), (5) and (6):

(1)#\[\dot{\Psi}=-\frac{1}{m\cdot \nu \cdot cos\theta}\cdot(-(P_{x_1}-\sum X_{p_1})\cdot cos\gamma_c \cdot sin\beta + (P_{y_1}+\sum Y_{p_1})\cdot sin\gamma_c+(P_{z_1}+\sum Z_{p_1})\cdot cos\beta +Z*)\]
(2)#\[J_{y_1}\cdot \dot{\omega_{y_1}}=\sum M_{y_1}+ \sum M_{py_1}\]
(3)#\[\dot{\psi}=\frac{1}{cos\nu}\cdot \omega_{y_1}\]
(4)#\[sin\psi=sin\Psi \cdot cos\beta \cdot cos\gamma_c + cos\Psi \cdot (sin\beta \cdot cos\theta + sin\gamma_c \cdot sin\theta \cdot cos\beta)\]
(5)#\[sin\gamma_c=tg\beta \cdot tg\theta\]
(6)#\[\dot{z_3}=-\nu \cdot cos\theta \cdot sin\Psi\]

  Equations describing only lateral motion cannot be solved independently, without considering the basic values determined by longitudinal motion. For example, in a system, the first equation is basic in determining lateral motion parameters, but it is solved only if m(t), v(t) and 0(t) are known. Aerodynamic forces and laterally acting moments cannot also be determined unless speed and altitude are known.

 At large trajectory rotation angles, it is necessary to check the limits of applicability of the formula determining Yc.

1.  Properties#

Property

Default Value

Description

Units of measurement

Initial value of the trajectory rotation angle

-13/57.3

-

rad

Yaw angle initial value

0

-

rad

Initial value of angular velocity of AD rotation

0

-

rad/s

Initial values for lateral displacement

0

-

m

2.  Inputs and outputs#

Parameters

Input/Output

Description

Units of measurement

Port type

\(v\)

Input

AD speed module

m/s

Automation

Theta (\(\theta\))

Input

Flight-path angle

rad

Automation

Tang (\(\upsilon\))

Input

Pitch angle

rad

Automation

P\(_y\)

Input

AD engine thrust in projection on the half-speed axis 0Z*

N

Automation

Z

Input

Aerodynamic force on axis 0Z*

N

Automation

MR\(_{y1}\)

Input

Projection of the moment in a related coordinate system on axis Y1

N\(\cdot\)m

Automation

J\(_y\)

Input

AD inertia moments

kg\(\cdot m^2\)

Automation

m

Input

AD mass

kg

Automation

PSI \(\Psi\)

Output

Trajectory rotation angle

rad

Automation

W\(_{y1}\)

Output

Angular speed of AD rotation relative to related axes

rad/s

Automation

psi \(\psi\)

Output

Yaw angle

rad

Automation

betta \(\beta\)

Output

Gliding angle

rad

Automation

gamma (\(\gamma_c\))

Output

Roll angle (angle between planes 0X1Y1 and 0XY*)

rad

Automation

Z

Output

Lateral offset

m

Automation

In order to see the connection capabilities of the block, you need to go to page Description of block ports