Development of a telerobotic test bench system for small-field-of-operation bilateral applications with 3D visual and haptic (kinaesthetic) feedback

[摘要] ENGLISH ABSTRACT:Teleoperation as a field has seen much change since its inception in the early 1940s with Dr.Raymond Goertz producing the first teleoperation system for manipulating radioactivematerials. With advances in core and supporting technologies, the systems have grownin complexity and capability, allowing users to perform tasks anywhere in the world irrespectiveof physical distance. The feasibility of such systems has increased as the drive foruse of telepresence robots, exploration robots as in space exploration, search and rescuerobots and military systems such as UAVs and UGVs gain popularity.This prompted the development of a proof of concept modular, user centred teleroboticsystem. The current project is the second iteration in the development process.Teleoperation and more specifically telerobotic systems pose a challenge for many systemdevelopers. This may be a result of complexity or the wide assortment of knowledge areasthat developers must master in order to deliver the final system. Developers have to balancesystem usability, user requirements, technical design and performance requirements.Several developmental process models are considered in context of Engineering Management(EM). A larger Systems Engineering developmental process is used, with focus onthe primary and supportive EM components. The author used a hybrid developmentalmodel that is user focussed in its approach, the User-Centred Systems Design (UCSD)methodology was adopted as the primary model for application within the two distinctdevelopmental categories. The first category hardware and system integration utilised theUCSD model as is. The second - Software development - relied on the use of agile models,rapid application development (RAD) and extreme programming (XP) were discussedwith XP being chosen as it could easily incorporate UCSD principles in its developmentprocess.Hardware systems development consisted of mechanical design of end-effectors, configurationmanagement and design, as well as haptic and visual feedback systems design forthe overall physical system. Also included is the physical interface design of the input(master) cell. Further software development was broken into, three sections, the first andmost important was the graphical user interface, haptic control system with kinematicmodel and video feedback control.The force following and matching characteristics of the system were tested and were foundto show an improvement over the previous implementation. The force magnitude errorat steady state was reduced by 10%. While there was a dramatic improvement in systemresponse, the rise time was reduced by a factor 10. The system did however show a decreasein angular accuracy, which was attributed to control system limitations.Further human-factor analysis experiments were conducted to test the system in two typicaluse-case scenarios. The first was a planar experiment and the second a 3D placementtask. The factors of interest identified were field-of-view, feedback vision mode, and inputmodality. Heuristic performance indicators such as time-to-completion and number of collisionsfor a given task were measured. System performance was only showed significantimprovement when used with haptic control. This shows that the research into hapticcontrol systems will prove to be valuable in producing usable systems. The vision factoranalysis failed to yield significant results, although they were useful in the qualitativesystems analysis.The feedback from post-experimentation questionnaires showed that users prefer the Pointof View as a field of view and 2D viewing over 3D viewing, while the haptic input modalitywas preferred.The results from the technical verification process can be used in conjunction with insightsgained from user preference and human-factor analysis to provide guidance for futuretelerobotic systems development at Stellenbosch University.

[发布机构] Stellenbosch University