... | ... | @@ -104,21 +104,22 @@ The **Non-systematic** involves variations in the surface and the internal uncer |
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| Right wheel diameter | 5.544 cm |
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| Track width | 16.27 cm |
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Why this behavior?
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Quantization error in tacho counter in each step of the trip.
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Orientation of back wheel.
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## Position tracking by means of particle filters
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### Estimating the noise factors
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The tests to performed to estimate the noise factors was performed at low speeds, on a wooden table covered by a single sheet of paper. The low speed reduces the noise factors because the wheel stops faster, and thus closer to the intended angle, also the low speed reduces the risk the wheel loosing grip of the surface. The wooden table covered by paper also reduces the noise factors, because the surface is homogeneously smooth, without any irregularities which could introduce errors.
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The distance noise factor was determined by having the robot perform multiple forward travels of 500 mm. The average distance from the target was ~0.5 mm, thus the distance noise factor was estimated as: 0.5/500 = 0.001.
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The angle noise factor was determined by two tests, both performed multiple times. In the first test, the robot perform four 360 degrees rotation. The second test was similar, but reversed the direction of the 2nd and 4th rotation. For both tests, the average deviation was 0.5 degrees, hence the angle noise factor was estimated as: 0.5/360 = 0.00138.
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## Position tracking by means of particle filters
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### Test with `PilotMonitor` and `PilotRoute`
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Hastighed ændret fra 5 til 15
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... | ... | @@ -133,6 +134,7 @@ Angle noise factor = 2.5 |
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## References
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[1] http://legolab.cs.au.dk/DigitalControl.dir/NXT/Lesson10.dir/Lesson.html
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[2] http://lejos.sourceforge.net/nxt/nxj/tutorial/WheeledVehicles/WheeledVehicles.htm
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