Trying to find a method to support an irregular shape at multiple points

[james_dewitt]

I have a 3D model of an irregular shape where the centre of mass is not within the structure itself. See image. Second image shows some indicative supports, which would be straps, to demonstrate what I am trying to achieve. I am trying to determine 3 hooking locations out of the available 8 so that when the structure is hoisted into place, there will be no rotation of the structure because it is critical that the structure maintains its level whilst it is being hoisted into place. I thought there might of been a way to do this using moments of inertia for each point. To no avail. Is there a standard engineering method for determining this? Can you point me toward some procedure/formula or British Standard?

I can provide further information/clarification if required.

Any help is much appreciated.

Thanks in advance. James.

[Kelly_Bramble]

How large is it and a hoisting fixture that is attached to the part may be the best answer.

[james_dewitt]

Hi Kelly, thanks for your reply.

Overall it is 4.6m x 1.95m.

HOIST POINT.PNG

See image of hoist points. We are hoping to utilise cleats positioned about the base to avoid attaching lifting eyes. The structure is exposed and would mean the lifting eyes would need to be cut off leaving a nasty finish.

Thanks again.

[jboggs]

If your objective is to remain level, then the locations of the individual connection points are unimportant as long as they enclose the center of gravity. Place your central suspension point some distance above the body. A higher suspension point produces less "wobbling" of the body. When you pick it up the CG will always be directly beneath the suspension point. Then just calculate the lengths of the individual distances to the connection points so make the body level.