gear.gms : Gear Train Design
A compound gear train is to be designed to achieve a specific
gear ratio between the driver and driven shafts. The objective
of the gear train design is to find the number of teeth of the
four gears and to obtain a required gear ratio of 1/6.931.
Reference:
- Deb, K, and Goyal, M, Optimizing Engineering Designs Using a Combined Genetic Search. In Back, T, Ed, Proceedings of the Seventh International Conference on Genetic Algorithms. 1997, pp. 521-528.
Small Model of Type: MINLP
$title Gear Train Design (GEAR,SEQ=203)
$ontext
A compound gear train is to be designed to achieve a specific
gear ratio between the driver and driven shafts. The objective
of the gear train design is to find the number of teeth of the
four gears and to obtain a required gear ratio of 1/6.931.
Deb, K, and Goyal, M, Optimizing Engineering Designs Using a
Combined Genetic Search. In Back, T, Ed, Proceedings of the
Seventh International Conference on Genetic Algorithms. 1997,
pp. 521-528.
$offtext
option optcr=1e-5;
Integer variables
a,f,b,d 'number of teeth in each of the gears (integer)'
Variables
z 'objective variable'
;
Equations
obj 'objective function'
sym1 'symmetry'
sym2 'symmetry'
;
Scalars
invgratio 'reciprocal of required gear ratio' / 6.931 /
minteeth 'minimum number of teeth' / 12 /
maxteeth 'maximum number of teeth' / 60 /
;
a.lo = minteeth; a.up = maxteeth;
f.lo = minteeth; f.up = maxteeth;
b.lo = minteeth; b.up = maxteeth;
d.lo = minteeth; d.up = maxteeth;
obj.. z =e= 1 + sqr(invgratio - (a*f)/(b*d));
sym1.. d =g= b;
sym2.. a =g= f;
* A better starting point than just the lower bounds
a.l = (maxteeth-minteeth)/2;
f.l = (maxteeth-minteeth)/2;
b.l = (maxteeth-minteeth)/2;
d.l = (maxteeth-minteeth)/2;
model m1 /all/;
solve m1 using minlp minimizing z;
Scalar calcinvratio ratio of solution
error absolute error;
calcinvratio = (a.l*f.l)/(b.l*d.l);
error = abs(calcinvratio-invgratio);
Display calcinvratio, invgratio, error;