Adams Car Package > Adams Car > Appendix > Steering Arm Toggle Angle

Steering Arm Toggle Angle

 
Description
The steering arm tie rod toggle angle is the angle measured from the tie rod to the steering arm in plane formed by steering arm and tie rod.
Units
Angle
Request Names
steering_arm.toggle_angle_left
steering_arm.toggle_angle_right
Inputs
Kingpin (steer) axis location (KPP) left and right
Kingpin (steer) axis unit vector (kpv) left and right
Tie rod to suspension upright location (TR0) left and right
Tie rod to steering location (TRI) left and right
Method
The vector T from the tie rod to the suspension upright location or tie rod outer (TRO) to the tie rod to steering system or tie rod inner (TRI) is given by the difference between the two locations:
T = TRI - TRO
For suspensions having a relay rod to transmit steering motion from one suspension upright to the other, the right side tie rod outer location is used as the left side tie rod inner. Likewise the left side tie rod outer is used for the tie rod inner for the right side. The cross product of T with the steering arm vector SA gives a vector N perpendicular to the plane containing T and SA
N = T x SA
And the cross product of N with T gives a vector B that lies in the plane formed by T and SA that is perpendicular to T
B = N x T
The unit vectors t and b in the directions of T and B are given respectfully by:
b = B/|B|
t = T/|T|
Finally, the steering arm toggle angle is given by the arc tangent of ratio of component of the steering arm vector in direction b to the component of SA in the direction of T:
steering_arm.toggle_angle = TAN-1((SA o b)/(SA o t))
Request Statements
Steering Arm Toggle Angle (and Length)
REQUST/id,   FUNCTION=USER(900,49,characteristics_input_array_id,0,   
, left_tie_rod_outer_id,    
, left_tie_rod_inner_id,    
, right_tie_rod_outer_id,    
, right_tie_rod_inner_id)/
Nomeclature
Bold text in uppercase letters, such as R, shows vectors.
Bold text in lowercase letters, such as u_lon, shows unit vectors.
X is the vector cross product operator.
o is the vector dot product operator.· * is the scalar multiplication operator.
| R | is the length (norm) of the vector R