Please help to design, a simple structure to

meet a given specification:

$$ Travelling crane to span hulls of an

oceanographic research vessel

$$ The truss span is $760$mm between rails

$$ The truss should be designed for a lift capacity

of $100$kg

$$ A clearance $60$mm high over a centre section

$80$mm wide is required

$$ The truss must be as light as possible

$$ There are no constraints on shape, size or

symmetry