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Changes for page Ball Physics

Last modified by Soeren Domroes on 2025/01/30 12:18
From version 7.1
edited by stu104225
on 2020/03/06 18:02
Change comment: There is no comment for this version
To version 2.1
edited by stu104225
on 2020/03/03 18:03
Change comment: There is no comment for this version

Summary

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Content
... ... @@ -1,130 +3,55 @@
1 -The **ball physics model**'s main objective is to provide a point in time to the controller, when the ball is predicted to be hittable, in order to not let the ball fall into the drain.
2 -
3 3  \\
4 4  
5 -\\
3 +== Task ==
6 6  
5 +The ball physics model is meant to do things ...
7 7  
8 -
9 -{{toc/}}
10 -
11 -== Ball trajectory ==
12 -
13 -----
14 -
15 -The trajectory of a ball can be modeled to be parabolic.
16 -
17 17  \\
18 18  
19 -
20 -\\\\like so: .... [TODO]
21 -
22 22  == Configuration ==
23 23  
24 -----
11 +=== Points of interest ===
25 25  
26 -=== Prediction parameters ===
13 +\\
27 27  
28 -(% class="wrapped" %)
29 -|=(((
30 -Parameter
31 -)))|=(((
32 -Description
33 -)))|=(((
34 -Default value
35 -)))
36 -|(((
37 -PREDICTION_FRAME
38 -)))|(((
39 -window size for prediction - How far
15 +[[image:attach:physics_points.png]]
40 40  
41 -into the future are predctions calculated at most.
42 -)))|(((
43 -70ms
44 -)))
45 -|(((
46 -PREDICTION_STEP_SIZE
47 -)))|(((
48 -size of the steps for the forward search
49 -)))|(((
50 -10ms
51 -)))
52 -|(((
53 -REFINEMENT_FACTOR
54 -)))|(((
55 -The prediction step size for the reverse search is
56 -PREDICTION_STEP_SIZE divided by REFINEMENT_FACTOR.
57 -)))|(((
58 -10
59 -)))
17 +=== Flipper range ===
60 60  
61 -When setting the PREDICTION_FRAME keep in mind, that predictions, that reach multiple frames into the future, are likely to be overwritten, when new frames arrive and new predictions are calculated.
62 -Nevertheless it is reasonable to calculate predictions beyond the next frame in case a ball is not recognized on the next frame.
19 +\\
63 63  
64 -With the default values up to 7 predictions are calculated if the ball is not predicted to be in flipper range roughly within the next two frames.
21 +\\
65 65  
66 -The REFINEMENT_FACTOR is also the worst case number of predictions calculated during the reverse search part of the prediction process.
23 +\\
67 67  
68 68  \\
69 69  
70 -=== Flipper range ===
27 +[[image:attach:physics2.png]]
71 71  
72 -The model of the area, where the the flippers can hit a ball is computed from a set of five points. These points are set to real world coordinates in meter
29 +\\
73 73  
74 -and should not need further adjustment after the camera is correctly calibrated (see [[doc:World Coordinate System]]).
31 +=== Inlane Area ===
75 75  
76 -The values for the left flipper are set to be symmetrical.
33 +[[image:attach:physics_inlane.png]]
77 77  
78 -[[image:attach:physics_points.png]]
35 +\\
79 79  
80 -(% class="wrapped" %)
81 -|=(((
82 -Point#
83 -)))|=(((
84 -Description
85 -)))
86 -|(((
87 -1
88 -)))|(((
89 -center point of the circle that the flippers tip moves o
90 -)))
91 -|(((
92 -2
93 -)))|(((
94 -highest point a ball can be at when it hits the resting flipper
95 -)))
96 -|(((
97 -3
98 -)))|(((
99 -lowest point a ball can be at when it hits the resting flipper
100 -)))
101 -|(((
102 -4
103 -)))|(((
104 -lowest point a ball can be at when it hits the fully triggered flipper
105 -)))
106 -|(((
107 -5
108 -)))|(((
109 -highest point a ball can be at when it hits the fully triggered flipper
110 -)))
37 +=== Prediction parameters ===
111 111  
112 112  \\
113 113  
114 -From these points an area, where the ball is deemed to be hittable, is computed.
41 +\\
115 115  
116 -[[image:attach:physics2.png]]
43 +\\
117 117  
118 118  \\
119 119  
120 -=== Inlane Area ===
47 +\\
121 121  
122 -Since the trajectory prediction does not consider collisions in general, we need a different kind of predictions for the inlanes,
123 -i.e. the path feeding a falling ball from the playfield to the flippers, behind the slingshot.
124 -A ball is considered to be in an inlane, when it is in a rectangualar area, with one edge given by the begin of the flipper
125 -and the other by a point at highest, outermost position of the angled part of the inlane.
49 +\\
126 126  
127 -In this area the vertical accelleration is deactivated in the prediction, since it would cause the prediction to assume the would slide into the wall.
128 -Though in reality the still is some accelleration, a simple linear prediction has shown to be practical in this less critical area.
51 +\\
129 129  
130 -[[image:attach:physics_inlane.png]]
53 +\\
54 +
55 +\\
Confluence.Code.ConfluencePageClass[0]
Id
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1 -71401657
1 +71401601
URL
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1 -https://rtsys.informatik.uni-kiel.de/confluence//wiki/spaces/PP18/pages/71401657/Ball Physics
1 +https://rtsys.informatik.uni-kiel.de/confluence//wiki/spaces/PP18/pages/71401601/Ball Physics