Simulation and execution of autonomous robot systems
(2002)- Abstract
- Traditional off-line programming is not enough in order to use the full potential of virtual models and simulation system in industrial robot applications. The interface between off-line programming system and the robot controller is today restricted to program transfer. In this way a large amount of information is lost since typical robot programming languages is rather limited.
If the virtual model could be accessed during the execution of the robot task, intelligent decisions could be made to avoid collisions, singularities, exceeding joint limits and poor process quality despite changes in the state of the robot workcell which not was anticipated in advance when the robot task was planned. Instead of a simple... (More) - Traditional off-line programming is not enough in order to use the full potential of virtual models and simulation system in industrial robot applications. The interface between off-line programming system and the robot controller is today restricted to program transfer. In this way a large amount of information is lost since typical robot programming languages is rather limited.
If the virtual model could be accessed during the execution of the robot task, intelligent decisions could be made to avoid collisions, singularities, exceeding joint limits and poor process quality despite changes in the state of the robot workcell which not was anticipated in advance when the robot task was planned. Instead of a simple feedback loop to the robot movement, the virtual model is continuously updated so the new information together with previous knowledge is accumulated in a common format. High level re-planning of the robot task can then be automatically performed.
An experimental system has been created that take advantage of the suggested approach. A commercial robot simulation system has been extended with new functionality for e.g. real time control of a physical robot, sensor feedback with automatic on-line calibration of the virtual model, robot tasks described in a high level language that can adapt to changes in the robot workcell and continuously supervision of the robot system to handle limitations without failing the task process. A modified industrial robot system have been used that allows low level joint control.
Gas Metal Arc-welding (GMA) have been the target process during experiments. It is a complex process that needs continuous corrections in a delicate cooperation between robot and process equipment. A seam-tracker have mainly been used as sensor to illustrate the possibility to close the control loop in the virtual system. (Less) - Abstract (Swedish)
- Popular Abstract in Swedish
Att ha tillgång till en världsbeskrivning under exekveringen av sensorstyrda robotsystem kan potentialen hos ett industriellt robotsystem avsevärt förbättras. Intellegent beslut kan baseras på den nominella informationen tillgänglig under planeringsstadiet och den nya informationen som erhålles från sensorer under körningen. Världsbeskrivningen kan då uppdateras kontinuerligt och kunskapen om omvärlden ackumuleras.
Genom att alltid ha en korrekt världsbeskrivning kan problem som kollisioner, överskridna axelgränser och ofördelaktiga kinematiska konfigurationer undvikas. Om man dessutom har en modell för tillverkningsprocessen tillgänglig kan små korrektioner av processen... (More) - Popular Abstract in Swedish
Att ha tillgång till en världsbeskrivning under exekveringen av sensorstyrda robotsystem kan potentialen hos ett industriellt robotsystem avsevärt förbättras. Intellegent beslut kan baseras på den nominella informationen tillgänglig under planeringsstadiet och den nya informationen som erhålles från sensorer under körningen. Världsbeskrivningen kan då uppdateras kontinuerligt och kunskapen om omvärlden ackumuleras.
Genom att alltid ha en korrekt världsbeskrivning kan problem som kollisioner, överskridna axelgränser och ofördelaktiga kinematiska konfigurationer undvikas. Om man dessutom har en modell för tillverkningsprocessen tillgänglig kan små korrektioner av processen avlasta roboten från problem som nämns ovan. I avhandlingen diskuteras bågsvetsning som exempel på tillvekningsprocess där metoden kan tillämpas. För denna process kan små korrektioner av pistol orientering drastiskt ändra förutsättningarna för roboten att lösa. Utan tillgänglig världsbeskrivning hade motsvarande uppgift troligen fått avbrytas.
För människan är det främmande att tänka sig att lösa en uppgift utan tillgång till våra sinnen. För industrirobotar är det fortfarande i allmänhet en realitet. Industrins avoga inställning till sensorer har två viktiga anledningar; den totala komplexiteten ökar med större kostnader och teknisk risk, samt att det är svårt att i förhand veta hur systemet kommer att bete sig då det är svårt att förutse alla möjliga situationer som kan uppstå. De föreslagna tekniken ger nya fördelar som möjligtvis kan ändra på detta. Genom att utnyttja sensorer inte bara för lokal korrektion utan en uppdatering av världsbeskrivningen i sin helhet kan den fulla potentialen av sensor informationen utnyttjas. En beskrivning görs också av hur virtuella sensorer kan utnyttjas i simulering innan systemet realiseras. Då kan robustheten studeras innan systemet används i produktion.
Industriella komponenter har använts i experiment för att verifiera metodens möjligheter. Tekniken går kanske inte direkt överföra till verklig produktion men det är författarens mening att det i avhandlingen har visats att det är rätt väg att gå för framtida industriella robot system. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/20508
- author
- Olsson, Magnus LU
- supervisor
- opponent
-
- Dr Murphy, Steve, ABB
- organization
- publishing date
- 2002
- type
- Thesis
- publication status
- published
- subject
- keywords
- robotics, Automation, Elektronik och elektroteknik, sensor simulation robotics, Electronics and Electrical technology, control engineering, Automatiska system, robotteknik, reglerteknik
- pages
- 100 pages
- publisher
- Div of Robotics, PO-Box 118, SE-221 00 Lund, Sweden,
- defense location
- M-building room E, Lund Institute of Technology
- defense date
- 2002-03-22 10:15:00
- external identifiers
-
- other:ISRN: LUTMDN/(TMMV-1051)/1-100/2002
- ISBN
- 91-628-5120-9
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Robotics (ceased) (LUR000026)
- id
- c6c35538-f99d-44fc-b879-43aae2025dc1 (old id 20508)
- date added to LUP
- 2016-04-04 11:30:58
- date last changed
- 2018-11-21 21:05:21
@phdthesis{c6c35538-f99d-44fc-b879-43aae2025dc1,
abstract = {{Traditional off-line programming is not enough in order to use the full potential of virtual models and simulation system in industrial robot applications. The interface between off-line programming system and the robot controller is today restricted to program transfer. In this way a large amount of information is lost since typical robot programming languages is rather limited.<br/><br>
<br/><br>
If the virtual model could be accessed during the execution of the robot task, intelligent decisions could be made to avoid collisions, singularities, exceeding joint limits and poor process quality despite changes in the state of the robot workcell which not was anticipated in advance when the robot task was planned. Instead of a simple feedback loop to the robot movement, the virtual model is continuously updated so the new information together with previous knowledge is accumulated in a common format. High level re-planning of the robot task can then be automatically performed.<br/><br>
<br/><br>
An experimental system has been created that take advantage of the suggested approach. A commercial robot simulation system has been extended with new functionality for e.g. real time control of a physical robot, sensor feedback with automatic on-line calibration of the virtual model, robot tasks described in a high level language that can adapt to changes in the robot workcell and continuously supervision of the robot system to handle limitations without failing the task process. A modified industrial robot system have been used that allows low level joint control.<br/><br>
<br/><br>
Gas Metal Arc-welding (GMA) have been the target process during experiments. It is a complex process that needs continuous corrections in a delicate cooperation between robot and process equipment. A seam-tracker have mainly been used as sensor to illustrate the possibility to close the control loop in the virtual system.}},
author = {{Olsson, Magnus}},
isbn = {{91-628-5120-9}},
keywords = {{robotics; Automation; Elektronik och elektroteknik; sensor simulation robotics; Electronics and Electrical technology; control engineering; Automatiska system; robotteknik; reglerteknik}},
language = {{eng}},
publisher = {{Div of Robotics, PO-Box 118, SE-221 00 Lund, Sweden,}},
school = {{Lund University}},
title = {{Simulation and execution of autonomous robot systems}},
year = {{2002}},
}