Right that’s external forces but what about forces acting internally? Take this column for example: What are the forces acting within it to stop it crumbling into a heap, whats keeping it in equilibrium? The column is under compression so it pushes up against the ceiling and down against the floor to balance the forces […]
So I’ve got structures, forces and how forces are applied but what if you have more than one force acting on an object at one time? Dean used a really good visual example: think about a tennis ball floating on a pond, a pump is pushing the water in one direction and a breeze is […]
So now I know the structure and forced involved… what about the application of those forces? Distributed - This is also known as a UDL (universally distributed load), it’s simply a load that it distributed along a surface. Concentrated – A load that is gathered on a point. Static – A load that does not move. […]
So here he is in all his glory: And finally… in flight! (sorry Dean didn’t have access to my video editing software!) You can see he’s still got a bit of clank and clunk in the movement but I think that it’s caused buy the weight rather than the mechanism. The Pegasus was made out of […]
Ok, I’ve got the types of structures down but what about the forces that act on them? Compression This action is when a substance is put under force from each end, like standing on a block of foam, it is being compressed between your feet and the floor. If the material subject to compression […]
So, my first foray into the wide world of structures… There’s tone of information so I’m going to detail as much of it as I can here to act as a reference. Structures can be broken down first into two categories: natural and manufactured Natural structures are classified as ‘not being made by people and […]
So, first, what is going to make my dragon fly? As a said before I think that the best mechanism to replicate the movement of the Pegasus will be a crank. A crank is basically a lever attached to a rotating shaft, the diagrams below are from a great book ‘Cabaret Mechanical Movement’ by Aidan […]
I’ve always loved dragons so I’m going to have a go at making an automata of a dragon flying. I got most of my inspiration from an automata made by a guy called Keith Newstead: I love the smooth motion! I think I’ve worked out that it’s made from a crank to describe the elliptical […]
Right, like linkages drive mechanisms (the collective term for pulley and gear systems) connect other mechanisms together but this time using rotary motion. This may also involve gearing or changing the angle or direction of the motion. There are two types of drives: positive and friction. Gears fall into the positive category as they are […]
Now we’re getting into the details… So, ready for more mathsy goodness? There are three important formulas to remember when dealing with mechanisms… Mechanical Advantage This is basically a comparison of the effort put in to the load moved, this leverage is the ration of the distances of the effort and load to the fulcrum. […]