resolution d'un system sous MATLAB

[ABN84]

bonjour,
j'essaie depuis tout à l'heure de resoudre ce systeme:

>> clear, syms theta1 theta2 theta3 theta4 theta5 theta6
>> eq1='-sin(alphay) = sin(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+sin(theta5)*sin(theta1)*sin(theta4)+cos(theta1)*sin(theta2+theta3)*cos(theta5)'
eq2='cos(alphaz) = (cos(theta6)*cos(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+cos(theta6)*cos(theta5)*sin(theta1)*sin(theta4)-cos(theta6)*cos(theta1)*sin(theta2+theta3)*sin(theta5)+sin(theta6)*cos(theta1)*cos(theta2+theta3)*sin(theta4)-sin(theta6)*sin(theta1)*cos(theta4))/cos(alphay)'
eq3='cos(alphax) = (-sin(theta2+theta3)*cos(theta4)*sin(theta5)+cos(theta2+theta3)*cos(theta5))/cos(alphay)'
eq4='x = 249*sin(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+249*sin(theta5)*sin(theta1)*sin(theta4)+249*cos(theta1)*sin(theta2+theta3)*cos(theta5)-1057*cos(theta1)*sin(theta2+theta3)+165*cos(theta1)*cos(theta2+theta3)+1075*cos(theta1)*cos(theta2)+410*cos(theta1)'
eq5='y = 249*sin(theta5)*sin(theta1)*cos(theta2+theta3)*cos(theta4)-249*sin(theta5)*cos(theta1)*sin(theta4)+249*sin(theta1)*sin(theta2+theta3)*cos(theta5)-1057*sin(theta1)*sin(theta2+theta3)+165*sin(theta1)*cos(theta2+theta3)+1075*sin(theta1)*cos(theta2)+410*sin(theta1)'
eq6='z = 775-249*sin(theta2+theta3)*cos(theta4)*sin(theta5)+249*cos(theta2+theta3)*cos(theta5)-1057*cos(theta2+theta3)-165*sin(theta2+theta3)-1075*sin(theta2)'

eq1 =

-sin(alphay) = sin(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+sin(theta5)*sin(theta1)*sin(theta4)+cos(theta1)*sin(theta2+theta3)*cos(theta5)


eq2 =

cos(alphaz) = (cos(theta6)*cos(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+cos(theta6)*cos(theta5)*sin(theta1)*sin(theta4)-cos(theta6)*cos(theta1)*sin(theta2+theta3)*sin(theta5)+sin(theta6)*cos(theta1)*cos(theta2+theta3)*sin(theta4)-sin(theta6)*sin(theta1)*cos(theta4))/cos(alphay)


eq3 =

cos(alphax) = (-sin(theta2+theta3)*cos(theta4)*sin(theta5)+cos(theta2+theta3)*cos(theta5))/cos(alphay)


eq4 =

x = 249*sin(theta5)*cos(theta1)*cos(theta2+theta3)*cos(theta4)+249*sin(theta5)*sin(theta1)*sin(theta4)+249*cos(theta1)*sin(theta2+theta3)*cos(theta5)-1057*cos(theta1)*sin(theta2+theta3)+165*cos(theta1)*cos(theta2+theta3)+1075*cos(theta1)*cos(theta2)+410*cos(theta1)


eq5 =

y = 249*sin(theta5)*sin(theta1)*cos(theta2+theta3)*cos(theta4)-249*sin(theta5)*cos(theta1)*sin(theta4)+249*sin(theta1)*sin(theta2+theta3)*cos(theta5)-1057*sin(theta1)*sin(theta2+theta3)+165*sin(theta1)*cos(theta2+theta3)+1075*sin(theta1)*cos(theta2)+410*sin(theta1)


eq6 =

z = 775-249*sin(theta2+theta3)*cos(theta4)*sin(theta5)+249*cos(theta2+theta3)*cos(theta5)-1057*cos(theta2+theta3)-165*sin(theta2+theta3)-1075*sin(theta2)

>> [theta1 theta2 theta3 theta4 theta5 theta6]=solve(eq1,eq2,eq3,eq4,eq5,eq6,theta1,theta2,theta3,theta4,theta5,theta6)

le probleme est que MATLAB calcule pendant pres d'une heure sans donner aucun resultat, je suppose donc que le systeme est trop complexe. comment pourrais-je m'y prendre pour le resoudre alors?
merci
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[ABN84]

bonsoir,
ce que je cherche c'est avoir l'expression des theta1-6 en fonction des alphax, alphay, alphaz, x, y, et z.
qqun aurait-il une petite idée sur comment s'y prendre?
merci