Skip to Content

Changes for page Project goals

Last modified by Alexander Schulz-Rosengarten on 2025/01/30 12:05
From version 4.1
edited by ssm
on 2014/05/05 18:40
Change comment: There is no comment for this version
To version 14.1
edited by Alexander Schulz-Rosengarten
on 2014/05/13 11:13
Change comment: added c interface header

Summary

Details

Page properties
Author
... ... @@ -1,1 +1,1 @@
1 -XWiki.ssm
1 +XWiki.als
Content
... ... @@ -13,6 +13,187 @@
13 13  Remember, you are going to present your controller at the end of the summer term! Getting this task done right is a very important step to succeed with your controller and this project!
14 14  {{/info}}
15 15  
16 +== **Goals** ==
17 +
18 +**The following goals should definitely be reached (if we get modules in Kieler):**
19 +
20 +* At least 5 trains can drive on the track at the same time
21 +* A "cleanup" function for trains should drive all trains to their original position
22 +* Our test scenarios should work (see Test-Scenarios)
23 +* The trains slow down before braking
24 +* All signals are working correctly
25 +* Gates should close, when a train is coming, and open again afterwards
26 +
27 +**In addition, the following optional goals might be reached, if there is enough time:**
28 +
29 +* Deadlock avoidance: Trains should never run into a deadlock
30 +* Cleanup function: All Trains which are still on the track travel to their next destination and afterwards they take the shortest way home
31 +* (((
32 +Trains should drive slowly at the points
33 +)))
34 +
35 +== **Road Map:** ==
36 +
37 +**
38 +**
39 +
40 +{{code}}
41 +13.5. Presentation
42 +27.5. Station-Station Controller + C-Interface
43 +17.6. Integrationstesting
44 +24.6. Defined testcases with stopflag
45 +01.7. Schedules for trains are working
46 +
47 +cw 34 Final presentation
48 +cw 35 Excursion to Miniatur Wunderland
49 +{{/code}}
50 +
51 +**
52 +**
53 +
54 +=== **Current work distribution: ** ===
55 +
56 +|=(((
57 +Task
58 +)))|=(((
59 +Assigned Persons
60 +)))
61 +|(((
62 +C-Inteface
63 +)))|(((
64 +Alexander
65 +)))
66 +|(((
67 +Mutual Exclusion
68 +)))|(((
69 +Nis
70 +)))
71 +|(((
72 +Station-to-Station
73 +)))|(((
74 +Personal assignments
75 +)))
76 +|(((
77 +Test Scenarios
78 +)))|(((
79 +Expert-groups
80 +)))
81 +|(((
82 +Deadlocks
83 +)))|(((
84 +Carsten
85 +)))
86 +|(((
87 +Integration
88 +)))|(((
89 +Small groups, dynamic time schedule
90 +)))
91 +
92 +== **Implementation in short:** ==
93 +
94 +The main idea is, that we have a universal model of the track segments. From these single track segments, track sections, that connect train stations are modeled and from those track sections, all final schedules for the trains should be build. On each track segment, there should be at most one train: In order to drive over a track, a train must request this track, and afterwards it must free it again (details below). If two trains request the same track section, the priority, which is derived from the train number, decides, which train gets the track section. A train must request all tracks until the next possibility to stop and wait in order to avoid collisions. If the train does not get all track segments, it must free them again in order to avoid deadlocks or delays of other trains. Deadlocks might occur at the exits of all train stations, and additionally, if one train with a low priority exits the Kicking-Horse-path while another train with a higher priority sends an entry-request. It remains to be seen, if additional deadlocks occur. Deadlocks can be resolved by using a superior Mutex-Controller.
95 +
96 +== **Implementation in detail:** ==
97 +
98 +**Basic Track:**
99 +
100 +The behaviours of a basic track is described as follows:
101 +
102 +**Sample Pass for one Track (in pseudocode)**
103 +
104 +{{code linenumbers="true"}}
105 +scchart Default_Pass {
106 + bool perm_next_Segment;
107 + initial state prev
108 + --> Gleissegment with 'contact(Segment,0)';
109 + state Gleissegment {
110 + entry / 'req(next_Segment)';
111 + entry / 'setSignal(prevSegment, red)';
112 + initial state Entry
113 + --> Continue with 'contact(Segment,0)' & perm_next_Segment
114 + --> Slowdown with 'contact(Segment,0)';
115 + state Slowdown {
116 + entry / 'setSpeed(Segment,SLOW)';
117 + }
118 + --> Waiting with 'contact(Segment,1)'
119 + --> Continue with perm_next_Segment;
120 + state Waiting {
121 + entry / 'setSpeed(Segment,BRAKE)';
122 + }
123 + --> Continue with perm_next_Segment;
124 + state Continue {
125 + entry / 'setSignal(Segment,green)';
126 + entry / 'setSpeed(Segment,full)';
127 + entry / 'setSpeed(nextSegment,full)';
128 + entry / 'setSignal(nextSegment, red)';
129 + }
130 + --> leave immediate;
131 + final state leave;
132 + region:
133 + initial state Entry
134 + --> cleanup with 'contact(Segment, 0)';
135 + state cleanup {
136 + entry / 'free(prevSegment)';
137 + entry / 'setSpeed(prevSegment,OFF)';
138 + }
139 + --> done immediate;
140 + final state done;
141 + }
142 + >-> next with 'contact(nextSegment, 0)';
143 + state next;
144 +}
145 +{{/code}}
146 +
147 +Behaviour modeled in an SCChart (without deadlock prevention):
148 +
149 +[[image:attach:csp_default_pass.png]]
150 +
151 +**Station-Station Modules**
152 +
153 +Input: train number, departure track, destination track, Cleanup flag, (mutex variables necessary?)
154 +Output: "real" destination track (alternative destination track)
155 +
156 +Modules needed:
157 +
158 +* KH-KH
159 +* KH-KH (other way round)
160 +* KH-IC
161 +* IC-KH
162 +* KH-OC
163 +* OC-KH
164 +* IC-IC
165 +* IC-OC
166 +* OC-IC
167 +* OC-OC
168 +
16 16  
17 17  
18 -Use this page to document your project goals...
171 +**Example for track segment requests (with 2 trains):**
172 +
173 +=== [[image:attach:nbw-mutex-sct.png]] ===
174 +
175 +**C-Interface**
176 +
177 +The C-Interface wraps some general functions, in order to prevent long and ugly host-code statements within the SCCharts. It especially hides the railway pointer. In addition, the C-Interface provides a persistent environment during a macro step. To bring in some randomness, the time, which a train has to wait in a station, is controlled by the C-Interface. Therefore, trains have to notify the interface about their arrival and their departure.
178 +
179 +[[Controller C Interface>>attach:controller.h]]
180 +
181 +
182 +
183 +**Test cases: **
184 +
185 +Our Implementation should pass the following simple tests:
186 +
187 +1. 3 trains travel from KH-Station to KH-Station in the main travel direction and 2 trains travel from KH-Station to KH-Station into the other direction. A possible problem might be the KH-Pass.
188 +1. 3 trains travel from IC-Station to IC-Station and 1 train travels from OC-Station via IC-Station to OC-Station. This test case tests the behavior of the IC_JCT.
189 +1. 3 trains travel from OC-Station to OC-Station and 1 train travels from IC-Station via OC-Station to IC-Station. This test case tests the behavior of the OC_JCT.
190 +1. 2 trains travel from IC-Station to IC-Station and 2 trains travel from OC-Station to OC-Station and 1 train travels from KH-Station via IC-Station to KH-Station. The problem here might arise from KIO_LN to IC_ST and from IC_ST to KIO_LN.
191 +1. Cleanup
192 +
193 +
194 +
195 +== **Organization** ==
196 +
197 +Meetings: Every Wednesday at 4 pm.
198 +
199 +
Confluence.Code.ConfluencePageClass[0]
Id
... ... @@ -1,1 +1,1 @@
1 -9470751
1 +9471137
URL
... ... @@ -1,1 +1,1 @@
1 -https://rtsys.informatik.uni-kiel.de/confluence//wiki/spaces/SS14Railway/pages/9470751/Project goals
1 +https://rtsys.informatik.uni-kiel.de/confluence//wiki/spaces/SS14Railway/pages/9471137/Project goals