Jump to content

Control of Heat Equation with Actuator Placement: Difference between revisions

From mintOC
No edit summary
Line 12: Line 12:
This problem is governed by the heat equation and is adapted from Iftime and Demetriou (<bib id="Iftime2009"/>).
This problem is governed by the heat equation and is adapted from Iftime and Demetriou (<bib id="Iftime2009"/>).
Its goal is to choose a place to apply an actuator in a given area depending on time.
Its goal is to choose a place to apply an actuator in a given area depending on time.
We consider a rectangle <math>\Omega=[0,1]\times[0,2]</math> with the boundary <math>\partial\Omega</math> and the time horizon <math>T=[0,10]</math> as the domains.
The objective function is quadratic, its first term captures the desired final state <math>\bar{u}\equiv 0</math>, the second term regularize the state over time and the third term regularize the continuous controls.  
The objective function is quadratic, its first term captures the desired final state <math>\bar{u}\equiv 0</math>, the second term regularize the state over time and the third term regularize the continuous controls.  
The constraints are a source budget, which limits the quantity of placed actuators, and the two-dimensional heat equation with some source function.
The constraints are a source budget, which limits the quantity of placed actuators, and the two-dimensional heat equation with some source function.
Line 25: Line 24:
\begin{array}{llcl}
\begin{array}{llcl}


\min\limits_{u,v,w}~~ &J(u,v)=||u(\cdot,\cdot,10)||_{2,\Omega}^2 +2||u(\cdot,\cdot,\cdot)||_{2,\Omega\times T}^2+\frac{1}{500}\sum\limits_{l=1}^L||v_l(\cdot)||^2_{2,T} &  \\[10pt]
\min\limits_{u,v,w}~~ &J(u,v)=||u(\cdot,\cdot,t_f)||_{2,\Omega}^2 +2||u(\cdot,\cdot,\cdot)||_{2,\Omega\times T}^2+\frac{1}{500}\sum\limits_{l=1}^L||v_l(\cdot)||^2_{2,T} &  \\[10pt]
     \text{ s.t.} ~~~~ &\frac{\partial u}{\partial t}(x,y,t)- \kappa \Delta u(x,y,t)=\sum\limits_{l=1}^9 v_l(t) f_l(x,y) &\text{ in }&\Omega\times T\\[10pt]
     \text{ s.t.} ~~~~ &\frac{\partial u}{\partial t}(x,y,t)- \kappa \Delta u(x,y,t)=\sum\limits_{l=1}^9 v_l(t) f_l(x,y) &\text{ in }&\Omega\times T\\[10pt]
     & u(x,y,t) =0    &\text{ on } &\partial\Omega\times T \\[10pt]
     & u(x,y,t) =0    &\text{ on } &\partial\Omega\times T \\[10pt]
Line 44: Line 43:
<math>
<math>
\begin{array}{rcl}
\begin{array}{rcl}
\Omega &=& [0,1] \times [0,2],\\
L &=& 9, \\
L &=& 9, \\
\kappa &=& 0.01,\\
\kappa &=& 0.01,\\

Revision as of 15:44, 23 February 2016

Control of Heat Equation with Actuator Placement
State dimension: 1
Differential states: 1
Continuous control functions: L
Discrete control functions: L
Path constraints: 3
Interior point equalities: 2


This problem is governed by the heat equation and is adapted from Iftime and Demetriou ([Iftime2009]Author: Orest V. Iftime; Michael A. Demetriou
Journal: {A}utomatica
Number: 2
Pages: 312--323
Title: {O}ptimal control of switched distributed parameter systems with spatially scheduled actuators
Volume: 45
Year: 2009
Link to Google Scholar
). Its goal is to choose a place to apply an actuator in a given area depending on time. The objective function is quadratic, its first term captures the desired final state u¯0, the second term regularize the state over time and the third term regularize the continuous controls. The constraints are a source budget, which limits the quantity of placed actuators, and the two-dimensional heat equation with some source function. Additionally, we assume Dirichlet boundary conditions and initial conditions.


Mathematical formulation

minu,v,wJ(u,v)=||u(,,tf)||2,Ω2+2||u(,,)||2,Ω×T2+1500l=1L||vl()||2,T2 s.t.ut(x,y,t)κΔu(x,y,t)=l=19vl(t)fl(x,y) in Ω×Tu(x,y,t)=0 on Ω×Tu(x,y,0)=100sin(πx)sin(πy) in ΩMwl(t)vl(t)Mwl(t) for all l{1,,L} in Tl=1Lwl(t)=1 in Twl(t){0,1} for all l{1,,L} in T.

Parameters

These fixed values are used within the model.

Ω=[0,1]×[0,2],L=9,κ=0.01,tf=10.

The parameter κ describes the thermal dissipativity of the material in the domain Ω, it may vary in space. The parameter L indicates the number of possible actuator locations. They are distributed as indecated in the picture.

Reference solution

Source Code

References

[Iftime2009]Orest V. Iftime; Michael A. Demetriou (2009): {O}ptimal control of switched distributed parameter systems with spatially scheduled actuators . {A}utomatica, 45, 312--323Link to Google Scholar