What should I do, as my submitted paper is still under review after 1 year? I'd just submitted a manuscript to Robotics &amp; Autonomous Systems Journal on Mar. 1st, 2015. Right after 1 month, its status changed to Under Review. I just waited up to Jan. 2016 and send a letter to editor-in-chief to clear the status of the paper and any potential problem due to this delay. He did say this after that 10 months!:


  you are right with your criticism. However your paper deals with
  research topics, where only a few of roboticist are familiar with.
  Hopefully we can get now the final required review. Sorry for the
  inconvenience.


Now, 2 extra months are passed, yet the paper's status is still Under Review.

They should have considered responsibility regarding the case. They could easily announce us about their inability to find any interested reviewer for the manuscript, and we would find the other journal. I'm frustrated a little bit. As a matter of fact, I am reluctant to withdraw the submission as they have wasted my time, NOTICEABLY, over the last year. I wonder if they have completely neglected it. 

Is there any way to handle this case, and ask them POLITELY and REASONABLY, leading to the finalization of this manuscript's situation?

Thanks

Edit: After 2 weeks from sending an email to the editor about the manuscript, he has not still replied.
I'm in a different field, but had a similar situation. I got a paper published in a journal in a matter of 6 months (submission to publication), then followed with another paper a month later. That paper was in review without notice for 6 months. After two unanswered emails, I politely asked for a decision on publication such that I might submit elsewhere if publication wasn't likely. This prompted them to respond that they were having trouble locating reviewers and asked for a list of potential reviewers. I received my reviews for the paper about 2 months later. It seems that if you suggest you might pull the paper and submit elsewhere, it may open a more honest conversation!