Current crane products

GANTRY:

This crane works by winching the weight up and sliding it along the top boom. It would be broken down and moved to the problem area and reassembled. Early possible problems I would like to investigate include; when the top boom is over four metres long will it deflect under a weight of 1000kg, are the feet stable enough and would it be better to have more legs on each end.  When at an end, would the supports be strong enough and would it cause the other end to be lifted?

SPIDER:

The spider crane mechanically moves to the required position, it then winches the load up and lifts it, it then carries it to the required area. Initial areas to investigate with this is how much this would cost, this could be a massive weakness with this design. Mechanically my worries include; not being heavy enough on the base causing it to tip over when lifting things with the crane head, would this design be able to get over serious obsticles associated with rubble covered areas.

JIB        

                                                             

The jib crane uses a fixed body, with a swinging arm to move what it has lifted it up. If used in this situation it would have to be carried to the desired point and the body would have to be dug into a solid foundation. Main concerns which I will have to investigate include; the crane being to heavy, not being able to dig the base into the ground because of the rubble and whether or not it would be pulled over when dug into the ground by the 1000kg weight being lifted up.

Calculations required to ensure quality:

Stress:  σ/y= M/I= E/R

Buckling: P_critical = 4π2EI/L^2 

Bending deflection: -EI(d^2 v)/〖dz〗^2 

Shear force: dM/dx

Important to ensure that at every point do the maximum stress equation. This will prove whether or not the material chosen will be successful. It is important to me that these equations are all considered to ensure that the crane will avoid failure.