Engineering Mechanics - Statics

pesisa

Can one obtain a negative value for mobility i when working out the mobility of a structure; the structure being constrained by either pins, sliders or fixed points? What happens with a negative mobility?

LabGuy330

you cannot have negative mobility.

Mobility is defined as "the number of independent parameters required to specify the position of all links of the mechanism." -Cleghorn 2005

These parameters are typically angles of links and distances of the base joints. If you are getting negative values for mobility it may be because the degree of freedoms of the links are incorrectly define.

If you can supply a diagram of the mechanism I would be glad to help.

pesisa

That helped me out a bit, but we already moved on onto other subjects now and I hope I passed the exam already. If not, I shall have to do a resit :( .. I can't understand why I found statics to be difficult and Mechanics to be much more simple, since the latter builds on the former.
I do have another question but I'm not sure I'm in the right place.
How do I treat distributed loads in Mechanics ?