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<Text-field style="Text" layout="Normal">Arthur Fleig, Marcus von Lossow, Tobias Ramming, Michael Schamel, Karl Worthmann</Text-field>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal">restart; with(LinearAlgebra):
A:=Matrix(6,6,[[0,1,0,0,0,0],[0,0,0,0,0,0],[0,0,0,1,0,0],[g/l[1],0,-g/l[1],0,0,0],[0,0,0,0,0,1],[g/l[2],0,0,0,-g/l[2],0]]):
B:=Matrix(6,1,[0,1/M,0,0,0,0]):
<Font encoding="UTF-8">printf(&quot;The matrices A and B are defined. We consider the linear control system\134n\134n&quot;);
</Font>diff(x(t),t)=A.x(t)+B.u(t);</Text-field>
</Input>
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<Input>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal">R:=proc(A::Matrix,B::Matrix)
	local i,n,S;
	description &quot;The procedure computes R(A,B) = [B, AB, A^2B, ..., A^(n-1)B]&quot;;
	n:=Dimension(A)[1];
	S:=Matrix(n,Dimension(B)[2],B);
	for i from 2 to n do
		S:=Matrix(n,i*Dimension(B)[2],[S,A.Column(S,i-1)]);
	od;
end proc:
Describe(R);</Text-field>
</Input>
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<Input>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal">Normalform:=proc(A::Matrix,B::Matrix)
	local i,n,S,T;
	description &quot;If the system is controllable, i.e., rk R(A,B) = n, the procedure will determine the normal form given in Theorem 3.2.3. 					Otherwise it computes the controllability decomposition&quot;;
	n:=Dimension(A)[1];
	if (Rank(R(A,B)) &lt; n) then
<Font encoding="UTF-8">		printf(&quot;Since the pair (A,B) is not controllable, we compute the controllability decomposition\134n\134n&quot;);
</Font>		S:=Matrix(n,Rank(R(A,B)),ColumnSpace(R(A,B)));
		T:=Matrix(n,n,[S,Matrix(n,n-Rank(R(A,B)),[convert(NullSpace(R(A,B)),list)])]);
		return(simplify(MatrixInverse(T).A.T),simplify(MatrixInverse(T).B));
	else
		S:=Matrix(1,n,Row(MatrixInverse(R(A,B)),n));
		for i from 2 to n do
			S:=Matrix(i,n,[[S],[Row(S,i-1).A]]);
		od;
		return(simplify(S.A.MatrixInverse(S)),simplify(S.B));	
	fi;
end proc:
Describe(Normalform);</Text-field>
</Input>
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<Input>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal">printf(&quot;We consider the case %a is not equal %a. Then t<Font encoding="UTF-8">he controllability matrix R(A,B) is given by\134n\134n&quot;, </Font>l[1], l[2]);
R(A,B);
printf(&quot;and has rank %d. &quot;, Rank(%));
<Font encoding="UTF-8">printf(&quot;Next, we determine, if possible, the normal form given in Theorem 3.2.3 via the procedure Normalform\134n\134n&quot;);
</Font>Normalform(A,B); N:=%[1]:</Text-field>
</Input>
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<Input>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal"><Font encoding="UTF-8">printf(&quot;In order to verify the obtained normalform, we check the coefficients of the last row. To this end, we compute the characteristic polynomial of the matrix A and compare the corresponding coefficients.\134n\134n&quot;);
</Font>p:=s-&gt;CharacteristicPolynomial(A,s): sort(p(s),s);
check:=0:
for i from 1 to Dimension(A)[1] do
	if (coeff(p(s),s,i-1)=-N(Dimension(A)[1],i)) then
<Font encoding="UTF-8">		#printf(&quot;Coefficient %a is correct\134n&quot;, alpha[i]);
</Font>		check:=check+1;
	else
<Font encoding="UTF-8">		printf(&quot;Coefficient %a = %a is not correct! The correct value is %a\134n&quot;, alpha[i], </Font>-N(Dimension(A)[1],i), coeff(p(s),s,i-1));
	fi;
	if (check=Dimension(A)[1]) then
<Font encoding="UTF-8">		printf(&quot;The normalform for the control system in consideration is computed succesfully.\134n\134n&quot;);
</Font>	fi;
od;</Text-field>
</Input>
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<Input>
<Text-field prompt="&gt; " style="Maple Input" layout="Normal">printf(&quot;We consider the case %a=%a. Then t<Font encoding="UTF-8">he controllability matrix R(A,B) is given by\134n\134n&quot;, </Font>l[1], l[2]);
R(subs(l[1]=l[2],A),B);
printf(&quot;and has rank %d. &quot;, Rank(%));
<Font encoding="UTF-8">printf(&quot;Next, we determine, if possible, the normal form given in Theorem 3.2.3 via the procedure Normalform.\134n\134n&quot;);
</Font>Normalform(subs(l[1]=l[2],A),B); </Text-field>
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<Text-field prompt="&gt; " style="Maple Input" layout="Normal"></Text-field>
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<Text-field style="Text" layout="Normal"><Equation executable="false" style="2D Math" input-equation="" display="LUklbXJvd0c2Iy9JK21vZHVsZW5hbWVHNiJJLFR5cGVzZXR0aW5nR0koX3N5c2xpYkdGJzYkLUkjbWlHRiQ2I1EhRicvJSxtYXRodmFyaWFudEdRJ25vcm1hbEYn">LUklbXJvd0c2Iy9JK21vZHVsZW5hbWVHNiJJLFR5cGVzZXR0aW5nR0koX3N5c2xpYkdGJzYjLUkjbWlHRiQ2I1EhRic=</Equation></Text-field>
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