IPOPT in acados

I was wondering if the IPOPT solver in CasADi can be used in acados.


As far as I know, NO.
If you want to use Ipopt, you can direct formulate your problem using CasADi. Optionally, if you work on optimal control problem, rockit might be interesting to look at, which focuses on direct methods but is built upon CasADi. It provides interface to call IPOPT as the underlying solver: