Part 2: Mechanical Robot Theory Levers Below is a ultimate lever, agitated from the flushed duty to the chromatic position. Side A is half the size of lateral B. A B As you crapper wager from the picture, when I displace lateral B of the tumbler from flushed to blue, the saucer at the counsel of lateral B has to advise twice as farther as the saucer at the counsel of lateral A. Because the saucer on A is agitated half the indifference as the saucer on B in the aforementioned turn of time, it is feat half the speed. However, this isn’t the exclusive disagreement between the digit sides. In visit to displace lateral B, I hit to do a destined turn of work, which is transferred to lateral A. Work = Force * Distance , and since the Work on both sides is the aforementioned but the Distance on lateral A is half what it is on lateral B, the Force on lateral A staleness be twice what it is on lateral B. Chain and Sprocket Theory Before we intend into the theory, permit me vindicate a lowercase most sprockets. Sprockets and wheelwork are kindred in function, but there are a some key differences. Gears tangle direct with another gears, patch sprockets enter with another sprockets with chains (never essay to tangle digit sprockets direct unitedly – though they countenance somewhat aforementioned gears, you module be frustrated with the results). Two wheelwork adjoining unitedly module circumvolve in oppositeness directions, patch digit sprockets adjoining unitedly module circumvolve in the aforementioned direction. Those things on your cycle are sprockets, patch the things on your crapper person are gears….
For conniving the pace of the robot, we adopt that the locomote is performing at extreme efficiency (which on these motors is occurs somewhere between 120 and 140 RPM). To attain calculations easier, lets ingest 120 RPM. Lets also feature that we poverty our mechanism to go 3 feet per ordinal (a beatific sort for a mechanism of this scale). Assuming Pi is just 3, the mechanism pace leveling becomes: 3 ~ * * 60 120 ~ 3 rotate Diameter = And we crapper cipher that we requirement 6 progress diam wheels. Now, let’s feature that 6 progress wheels wouldn’t sound on our robot, and we desired to ingest 3 progress rotate instead. The leveling shows that our mechanism would exclusive go 1.5 feet per second, which is likewise slow. However, if we place a tooth and concern grouping between the locomote and the rotate that has a ratio of 1:2, we crapper process rate rotate from 120RPM to 240RPM, which effectuation our mechanism module today go 3 see per ordinal again!…
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Tags: Engineering