Automated way to do multilingual in existing rails application

I have existing rails application . Currently no language support and now need to do language support . Is there any tools , gem etc which will help me to find static word from erb/helper/model etc files . It will be best if find static word and auto generate at least one yml file . If I will go for manual it will take 6 months to finish total more then 3000 of erb files and human error can come . So please suggest if any easiest way to do this .