Last week during lab we had the task of testing our bridge design. We had two designs, one was unofficially tested and preformed better that the first one. The first design that was tested wasn't very successful because it depended on a arch structure that supported it self on the sides of the supports. this wasn't very reliable because the two saw horses aren't completely attached to the ground so when weight was added to the bridge the arch supports moved the supports to the sides as the weight went down, this first one only supported 16 lbs. Our second design was a much more typical truss bridge, so this didn't have the problem of moving the saw horses to the sides. This design supported around 32 lbs.
One of the things that will surely make our bridge design much better will be how we analyze the forces that act on each of the knex pieces. If we would know the stresses of each of the pieces we would be able to take out all the unnecessary pieces and include pieces that would help support more weight. The way I would approach this force analysis would be to take the different structures that make the bridge and simulate extreme forces that they would experience. For example I would take a simple two truss bridge and add weight to it until it failed, test various different setups and choose the most effective.
No comments:
Post a Comment