Two composite guidance laws based on the backstepping control and disturbance observers with autopilot lag

Abstract

A composite three-dimensional (3D) missile guidance law is proposed for manoeuvering targets with the consideration of the first-order autopilot dynamics without any linearization. This guidance law consists of a backstepping controller and a feedforward compensation based on disturbance observers. In this control scheme, the unknown target acceleration is regarded as part of the lumped disturbance, estimated by a disturbance observer, and then feedforward compensated. The backstepping controller is introduced to deal with unmatched disturbances. Moreover, both the nonlinear disturbance observer (NDOB) and the generalized proportional integral observer (GPIO) are employed in the derivation. Simulation studies demonstrate the effectiveness of the proposed guidance law, and compare the guidance performance of the two composite guidance laws with different disturbance observers.

Fixed-Time Convergent Guidance Law with Angle Constraint and Autopilot Lag Compensation Using Partial-State Feedback

“…Theorem 2. Considering the system (9) adopts the fixed-time convergent guidance law (23), then s = 0 can be guaranteed in fixed time. And the system states x i (i = 1, 2, 3) can converge to zero in a fixed time for any initial condition x i (0) ∈ R (i = 1, 2, 3) and r(0) ∈ R.…”

“…Thus, considering autopilot lag compensation (ALC) is necessary. Many guidance laws have considered eliminating the bad effect of autopilot lag by using modern control methods, such as the backstepping control method [23], exact differentiator [24], dynamic the surface control method [25], etc. However, so far, only a few finite-time convergent guidance schemes have considered both effects of AC and ALC.…”

Time-energy optimal guidance strategy for realistic interceptor using pseudospectral method

“…Application of non-linear control theory to missile guidance with initial high heading errors have been the subject of many research papers (Bezick et al, 1995; Man et al, 2019; Si and Song, 2018; Taur, 2002). The first guidance law that reported successful interception of the target was the proportional navigation (PN) law (Adler, 1956).…”

Adaptive fin failures tolerant integrated guidance and control based on backstepping sliding mode

“…Although it is still attractive to separately design the guidance and control subsystems, it is known the integrated guidance and control (IGC) method can enhance hitting performance (Menon and Ohlmeyer, 2001). In order to achieve the high-performance interception in presence of maneuverable target, many control theories have been used to solve the IGC problem (Baohua and Changsheng, 2009; Fu et al, 2017; Guo et al, 2019; Hwang and Tahk, 2006; Lianos et al, 2001; Man et al, 2019; Menon et al, 2003; Sharma and Richards, 2004; Shima et al, 2006; Shtessel et al, 2009; Vaddi et al, 2009; Xin et al, 2004; Yan and Ji, 2012; Yan et al, 2014).…”

“…Yan et al (2014) designed an adaptive IGC law based on backstepping and input-to-state stability scheme for homing missiles facing maneuvering targets. A three-dimensional missile guidance law using the backstepping controller and a feedforward compensation based on disturbance observers are proposed by Man et al (2019). Besides, several other control techniques are developed with IGC such as θ-D method (Xin et al, 2004), subspace stabilization (Baohua and Changsheng, 2009), state-dependent Riccati equation (Vaddi et al, 2009), linear quadratic optimal theory (Menon et al, 2003) and small-gain theorem (Yan and Ji, 2012).…”