You wait all day for an autonomous Volvo concept loader, and then two come along at once. Or so the saying goes. Following the 42081 Volvo Concept set, LEGO and Volvo have teamed up to run a competition to design the Volvo construction vehicle of the future.

Here are two entries, each packed with Power Functions motors and remote control functionality, and each looking quietly terrifying to boot.

First up (above) is R. Skittle‘s ‘Volvo Proteus’, a fully autonomous self-loading hauler. Many many motors power the loader’s drive, all-wheel-steering, the huge swivelling bucket arm, and the sliding and tipping bucket, and there’s much more to see at Skittle’s photostream. Click the link above to view the full gallery of this superbly engineered creation.

Today’s second concept (below) sends Volvo into space, with this enormous ‘Mars Mission’ loader/dozer/tunneller/excavator, all the things required for some Mars-based construction. Built by Desert Eagle (aka Desert752) of Eurobricks this metre-long monster is powered by sixteen motors, with all-track drive, crab steering, a self-levelling superstructure via linear actuators, 360 degree excavator boom rotation with elevation, extension and a synchronised counterweight, 360 degree tunneller boom rotation and elevation, and a drill head that looks like something from your Mom’s Ann Summers chest.

There’s a whole lot more to see of both of today’s Volvo concepts via the links above, and you can enter the competition yourself via LEGO Ideas by clicking here.