"I came to browse the Internet and build robots. And I am done browsing the Internet". Many different approaches, principles and directions to constructing robots with detailed building instructions and pictures.
Active robot attachment for the LEGO Mindstorms EV3 Box robot chassis. The attachment is placed on the top of the robot and uses a system of two gear wheels to transfer the motion to a lever and to .... lift things.
This robot was built by your request. It includes NXT large wheels. The Large LEGOO Mindstorms wheels will give you a faster robot, but be careful, because it will not be that accurate.