Need help with this questions. Need details, like free body diagram. Thank you s
ID: 1845934 • Letter: N
Question
Need help with this questions. Need details, like free body diagram. Thank you so much!!
For the electromechanical system shown in figure 4, determine the transfer function X(s) / F(s) using the free-body diagram, where f(t) is the applied force, x(t) is the displacement of the mass, k is the spring constant, and c, is the damping constant of the dashpot and the friction coefficient. Using the results of PLA-1, write the transfer function C(s) / R(s) of the system shown in figure 4. Assume KEMS = KsKenc. Given the step response of a system shown in figure 5, write the transfer function of the prototype second-order system in the form of equation (1). and find zeta and omegan n of the response using equations (2) and (3). Using the results of PLA-2 and PLA-3, find the values of KEMS, c, and k in terms of m. Note that for the ECP system, m is mass of the carriage and the additional known mass of the brass weights, c is the damping constant of the dashpot plus the friction coefficient and k is the stiffness of the spring.Explanation / Answer
1.
from the figure we can write the governig equation as
f(t) - kx -cx' = mx'' where x' and x'' represents the first and second derivative of x w.r.t t.
taking laplace transform we get
F(s) = X(S)*(mS^2 + cS + k)
so
X(S)/F(S) = 1/((mS^2 + cS + k))
2.
we have
X(S)/F(S) = 1/((mS^2 + cS + k))
now
from the figure
C(S) = X(S)*(Kenc*Khw)
or
C(S) = F(S)*1/((mS^2 + cS + k))*(Kenc*Khw)
now
F(S) = R(S)*K(S)
so
C(S)/R(S) = (K(S)*(Kenc*Khw))/((mS^2 + cS + k))
3.
equating both the equations we get
Wn = sqrt(K/m)
and
gi = c/(2*sqrt(mK))
4.