Q2. What are the design tools for the UMTI?
The design tools mainly consist of adaptive control, sliding mode control, high-gain control, etc. In [7],Preprint submitted to Aerospace Science and Technology April 3, 2018the authors parameterize upper bounds of the target acceleration and then develop the resulting parameter adaptive laws, thus handling the target maneuver.
Q3. What are the conditions needed to achieve intercept?
To achieve intercept, three conditions are needed: ! = 0, sin(M )a Msin( T )a T , and ṙ0 < 0, where ṙ 0 is the initial interceptor-target range rate.
Q4. What is the objective of the two guidance laws?
The objective of dealing with the control saturation in these two guidance laws is to enable the adaptive laws to work so that the parameters of the target maneuvers can be e↵ectively estimated.
Q5. What are the fundamental concerns in adaptive control design?
As such, the control saturation and the speed of the parameter adaptation are two fundamental concerns in adaptive control design [8, 9, 10].
Q6. What is the auxiliary signal in the fast adaptive guidance law?
A fast adaptive guidance law in [11] induces an auxiliary signal to prevent the control saturation from destroying the parameter adaptation.
Q7. how is the zero solution of the observation-error dynamics?
0. Using LaSalle’s invariance theorem, the zero solution of the observation-error dynamics (13) is globally asymptotically stable.
Q8. What is the initial position of the interceptor?
In the simulation, the interceptor’s initial position is set at the origin, its initial velocity is 1000m/s, and its initial flight path angle is 50 deg.
Q9. What is the LOS rate in Case 7?
As described in Figs. 3c and 3d, the LOS rate in Case 7 is quickly nullified after the sudden change of the target maneuver at 5 s, while the LOS rate in Case 8 is stabilized through a relative large transient period due to the control saturation, which is the adverse impact of the large magnitude of the target acceleration.
Q10. What is the LOS rate of the closed-loop CFTDO?
Using the RFTG law (10), together with = ↵, the closed-loop closed-loop LOS rate dynamics are given by!̇ = c 1 |!|↵ sgn(!) + e d ,ė!
Q11. What are the drawbacks of adaptive guidance laws?
Although the adaptive guidance laws work well in the above-mentioned scenarios, they have three drawbacks herein: 1) the guidance performance heavily depends on the convergence of adaptive parameters, while these parameters are easily prone to diverge when the jerk of the maneuverable target is considerable; 2) the robustness to the target maneuver relies on the parameterization of the target maneuver, while it is very hard to accurately parameterize the target maneuver under study; 3) the order of the closed-loop guidance system will inevitably increase as the dimension of the adaptive parameters grows.