MrPots, I can only agree with the general vibe of this thread.
You CANNOT endanger your child for the sake of politeness. Your parents need to accept this and take reasonable measures to ensure that you can visit without fearing for your child's safety.
The dogs need to be at the very least out of the room, or crate-trained, if your parents want to see you and their grandchild(ren?).
Why do you say, "shutting the dogs away isn't an option?" I hope it isn't because they are blind to the potential risk they are placing your daughter at by refusing to acknowledge their pets' volatile temperaments.
My dog will never be allowed near children, he is very nervous, and they frighten him; this manifests itself in an aggressive way, and I would never put him in a situation where anything could happen. I make sure he isn't walked around 9am or 3pm, near playparks at weekends etc.
What are your parents' "commitments"? Could they not take a couple of days off to visit? After all, it's a 2-way relationship, it shouldn't be you doing all the running, which it sounds like it is.
I know it's not a comfortable subject, but you need to be very direct with your parents. Just be assertive: tell them that you enjoy visiting, and that you want them to continue see their grandchild frequently, but that you will not be putting her in danger, and they need to deal with their dogs somehow so she is not at risk.
Good luck.