Mission monitor sequencer: Difference between revisions
(→Plan) |
m (Corrected spelling) |
||
Line 47: | Line 47: | ||
</plan> | </plan> | ||
A number of these plans can be started (enabled) simultaniously, an can in principle be total independant. I.e.one can control the robot arm | A number of these plans can be started (enabled) simultaniously, an can in principle be total independant. I.e.one can control the robot arm while another controls the navigation. | ||
===Language definition=== | ===Language definition=== |
Revision as of 14:01, 21 September 2008
Introduction
This plug-in implements a a language that is a mixture of a rule-based and a sequential based language. The idea is that a number of situations need permanent - or semi permanent - monitoring to get a good situation awareness for the root, and at the same time a large number of the robot tasks are better described by a sequential language.
This implementation attempts to cover this gab.
Language
An example function could look like this:
<?xml version="1.0" ?> <plan name="CrossRoad"> <init> odoPose.tripB = 0 nearRoad = false // define local variable <plan name="maxOdoDist" if="odoPose.tripB > 250"> print("Driven too far on odo " odoPose.tripB "m") // print message break CrossRoad // failed to cross road - could trigger a relocalization </plan> <plan name="closeToRoad" if="hypot(utmPose.poseY - 6174307, utmPose.poseX - 707873) < 15" > print("Cose to road slowing down) // print message smr.speed=0.5 // set the desired maximum speed in mrc interface module nearRoad = true // set flag disable // disable this rule (plan) </plan> <plan name="turn"> <parameter angle="pi" dist=1.0/> <commands to="smr.send"> # construct commands to MRC using the smr.send command 'drive @v ' smr.speed ' : ($drivendist > ' dist ')' 'turn ' angle 'drive : ($drivendist > ' dist ')' </commands> </plan> </init> print("started") enable maxOdoDist // should have found road by now enable closeToRoad // active until disabled. roaddrive.right(0.75) : nearRoad // follow road 75cm from edge until near road // more stuff missing here to detect traffic etc. ... turn() // turn back - using a call to a plan success=true <post> print("finsihed crossRoad - success=" success) </post> </plan>
A number of these plans can be started (enabled) simultaniously, an can in principle be total independant. I.e.one can control the robot arm while another controls the navigation.
Language definition
The language definition is:
Plan
planBlock ::= planOpenTag planBody planCloseTag
planOpenTag ::= '<plan' 'name=' planName [runAttribute] [ruleCondition] '>\n'
planName ::= '"' symbol '"'
runAttribute ::= 'run="default"' (there may come more values later)
ruleCondition ::= 'if="' expression '"' (this expression may be split into more lines)
planCloseTag ::= '</plan>\n'
planBody ::= [parameters] [description] [planInitBlock] planMainBlock [planPostBlock]
parameters ::= '<parameters ' [symbol '="' [paramDefaultValue] '"']* '/>\n'
paramDefaultValue ::= constantValue
description ::= '<description>\n' xmlText '</description>\n'
xmlText ::= any 7-bit characters except '\0', '&' and '<', the last two must be coded as & and <
planInitBlock ::= '<init>\n' [declarationStatement]* '</init>\n'
declarationStatement ::= planBlock | executableStatement
planMainBlock ::= [statement]*
planPostBlock ::= '<post>\n' [statement]* '</post>\n'
Statements
statement ::= executableStatement | controlStatement
executableStatement ::= assignment | procedureCall | blockStatement | breakStatement | enableStatement | ifStatement | emptyStatement
controlStatement ::= proceureCall ':' expression [remark] '\n'
assignment ::= [symbol.]* symbol '=' expression [remark] '\n'
procedureCall ::= [symbol.]* symbol '(' [expression [',' expression]* ')' [remark] '\n'
blockStatement ::= '<block>\n' [statement]* '</block>\n'
breakStatement ::= ('break' [symbol] | 'continue' ) [remark] '\n'
enableStatement ::= ('enable' | 'disable') [symbol] [remark] '\n'
ifStatement ::= 'if (' expression ')' [remark] '\n' statement [remark] '\n' [elseStatement]
elseStatement ::= 'else' [remark] '\n' statement [remark] '\n'
emptyStatement ::= [remark] '\n'
remark ::= ('#' | ';' | '//') xmlText except '\n'