Maximaでバネ型モデルを描画

plot3d(
        [(5+cos(s))*cos(t)
        ,(5+cos(s))*sin(t)
        ,sin(s)+0.9*t]
        ,[s,0,2*%pi]
        ,[t,0,7*%pi]
        ,[grid, 15, 150]
        ,[box, false]
);