remove empty bibliography

content/zettels/anti_windup_control.md

@@ -22,16 +22,16 @@ In order to implement anti-windup, the integrator usually has to be **explicit**
 This is one of the reasons why the PID controller is so useful: the integral action is clearly separated from the other terms.
 
 
-### Anti-windup strategies {#anti-windup-strategies}
+## Anti-windup strategies {#anti-windup-strategies}
 
 
-#### Conditional integration (integrator clamping) {#conditional-integration--integrator-clamping}
+### Conditional integration (integrator clamping) {#conditional-integration--integrator-clamping}
 
 The integrator is simply stopped (or reset) when the actuator is saturated.
 For instance, the integration is frozen as long as \\(u \neq \text{sat}(u)\\), possibly only if the error would further increase the saturation (i.e. same sign of \\(u\\) and \\(e\\)).
 
 
-#### Back-calculation {#back-calculation}
+### Back-calculation {#back-calculation}
 
 The difference between the saturated and the requested control signal, \\(e\_s = \text{sat}(u) - u\\), is fed back to the integrator input through a gain \\(1/T\_t\\):
 
@@ -42,9 +42,3 @@ The difference between the saturated and the requested control signal, \\(e\_s =
 When there is no saturation, \\(e\_s = 0\\) and the controller behaves as usual.
 When saturated, the integrator state is driven so that \\(u\\) tracks the saturation limit.
 The tracking time constant \\(T\_t\\) sets how fast the integrator is unwound (a common choice is \\(T\_t = \sqrt{T\_i T\_d}\\) or \\(T\_t = T\_i\\)).
-
-
-## Bibliography {#bibliography}
-
-<style>.csl-entry{text-indent: -1.5em; margin-left: 1.5em;}</style><div class="csl-bib-body">
-</div>