Find the acceleration in a composition of movement

[shero1040]

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Hello,
l need to find the acceleration in the D point but i don't know how.
the 2 circles turn in the same speed ( pi rad/s).

I use a simulation programme to find the D acceleration ( - 1643 mm/s^2) but how to find it with a mathematical approach ?

Sorry for my english

 

[mfb]

I don't understand what is fixed to what and I don't see point D.
Anyway: introduce variables for relevant positions, express your constraints (distances, angles, ...) in terms of those variables, solve the resulting equation system for the position of D. If that turns out to be impossible analytically, use numeric solutions.