User blog comment:Lord Skarpo/Useful Builds/@comment-27434301-20151229130734

Animal grinder - allows you to get food and drops easily and efficinetly without the need of wasting durablity on your precious sword

How to Make an Automatic Animal Grinder in MCPE

Click on the link above, it's a tutorial video showing how to build an animal grinder which you can build in surival and no redstone is required.