Pedal timpani are well established instruments, offering the convenience of rapid tuning; they are now almostuniversal in orchestral music. However there are two major problems associated with them, namely their high cost and their huge size and weight.

Tour Timps were specifically designed to offer a sound very similar to conventional timpani, but allowing for easier transport and storage at a more affordable price.

I'm thinking of buying some, so I've included the link for reference.