I want you to picture a cake, sitting on its own, perfectly still, when a rolling basketball comes crashing into it and then the cake's layers suddenly separate and vertically hop upwards. Now, what kind of motion do you see in that scenario? well, let's see, we saw the rolling ball is going through rotational motion and then that rotational motion was suddenly transformed, abruptly, into translational motion, straight up and down or left and right, so in this lesson we are going to look at the technological systems that actually do transform motion. They are called motion transformation systems and we are going to look at the different types.
First of all let's define what a system is. All systems contain a component called a driver, this is the component that receives the motion, a component called the follower, this is the part that receives that motion and gets it transformed into something else and the intermediate, which may or may not exist in a technological system, next the driver and the follower.
In motion transformation the nature of the motion is changed as it goes from one part to another, so the driver and driven component (driven component is another word for follower) they do not have the same motion. For example you may have translational becoming rotational, rotational becoming translational and so forth.
These are the four system types we are going to look at: the slider crank, rack and pinion, cam followers and screw gear, so let's dive right into it.
In a slider-crank, its main function is that it transforms rotational motion into translational. As you can see, the components that contains is a connecting rod and a crank. The crank is a part to which rotational motion can be applied and the rod is intermediate. The rod connect the crank to another object that moves it translationally.
Now in a rack-and-pinion system, it has a rack which is a rod with teeth and a pinion which is a gear wheel. The teeth of the components must mesh together or it will not function as a system.
Now in a cam and follower system there are no intermediate, you simply have a cam and a follower. The cam is the irregular shaped disk, it's not a perfect circle, it's irregular and the follower is the rod. Now the cam turns, that's rotational motion, and the follower is translational motion, so it makes a back-and-forth movement.
The screw gear is something you're probably very familiar with already. Its components are one screw and one nut at least. Take it out more than that, if you've ever built something before, you may have already used a c-clamp, that is a screw gear system example. That's all for now, see you next time!
