Mobile – robot remote control and

communication system design

P. Petrova, R. Zahariev

Central Laboratory of Mechatronics and Instrumentation Bulgarian Academy of Sciences

Telerobot-Control and Communication 2

Telerobotics

• Introduction– History and use of Telerobots– Virtual Reality

• Teleoperation– Teleoperation and Telepresence– Tele-action

• Interfaces– Wireless connections: Wi-Fi, Bluetooth– “threaded” connections– Internet

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Main Applications

• Exploration, monitoring and surveillance– Space exploration

– Underwater/surface exploration

– Wildlife observation

– Fire awareness monitoring

– Debris cleaning and human rescue

– Spy-robots

• Household and education– Household appliances control

– Virtual simulators and games

– Virtual-distance laboratories

• Manipulations from distance, indirect manipulations– Bomb defusal

– Tele-surgery

– Nuclear decontamination and decommissioning

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Telerobot Characteristics

• Operation mode– Autonomous cyclic operation

– Semi-autonomous – surveillance algorithm can be interrupted by operator

– Operator-controlled

• Control interfaces– Combination of several interfaces working interchangeably

– Possible direct (RF) or indirect (Network) control

• Structure– Form

– Components

– Movement method – wheels, caterpillar tracks stc.

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Hardware

Mobile – Robot components:• Monitoring – camera and microphones • Sensors – possibility for night vision (IR), distance sensors,

obstacle sensors• Autonomous power supply – long lasting, easy changeable/

rechargeable, power saving operation • Local data storage – backup

Network components:• Server PC• Client PCs

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Access Types

• SOSR, single-operator multiple-robot– Most networked robots are SOSR, where control is limited to one

human operator at a time– each operator controls one robot arm and the robot arms have

overlapping workspaces

• MOMR multiple-operator multiple-robot– MOMR models are also relevant to on-line collaborative games,

where players remotely control individual avatars in a shared virtual environment

• SOMR single-operator multiple-robot– one human operator controls multiple robots. A variant is no-operator

multiple-robot (NOMR) systems, sometimes called collaborative or cooperative robotics, where groups of autonomous robots interact to solve an objective

• MOSR multiple-operator single-robot– serial pipelined communication, with overlapping plan and execution

phases; such collaboration improves overall execution time, but do not address conflict resolution between user

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MOSR Network Structure

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System Structure

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Communication Software

• Top Level – Server-Client-based– Server application

– Client application – Java based applet

• Low Level – embedded– Embedded C/C++ based control program

– Global trajectory planning

– Obstacle avoidance and smoothing algorithms

– GPS information and control

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GUI

• Off-the-shelf realization -LabView– Widely used software

environment– Facilitates modification

of functionality– Enables visual robot

programming• Custom-made realization –

Visual C++– Component-based

software approach– Low-level control

functions integration– Library implementation

•Graphical programming techniques can be used the implementation

LabView

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Software Operation Modes

• Access– Direct online monitoring – “live” feed – robot -> operator

– Downloadable client-server applications – bidirectional communication

– Direct RF control – short range - bidirectional

• Data transfer and storage– Server side data storage

– Data visualization – calculations and formatting algorithms

– Online activity history

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Security Issues

• Hardware reliability in hazardous environment• Operations queue – prioritization• Malicious activity reliability• Platform independency• TCP advantages/disadvantages• User Access/Registration – management

– Do we want anybody to be able to access and operate the robot?

• Operation mode management

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Conclusions

• The described architecture provides versatility to the mobile-robot, allowing for application modification

• The combination of commercial and custom-designed software facilitates the design and provides higher reliability

• The system could enhance the conduction of some on-field measurement experiments, allowing “on-line” access without necessary human presence