Voice Command Generation for Teleoperated Robot Systems

1. Voice Command Generation for Teleoperated Robot Systems Authors : M. Ferre, J. Macias-Guarasa, R. Aracil, A. Barrientos Presented by M. Ferre. Universidad Politécnica de Madrid (Spain)

2. Commands by voice • Voice is the most natural way for human communication • Multimedia interfaces allow communication by voice • Some telerobotics systems have been commanded by voice

3. The Speech Engine • It is based on an isolated word recognition system • It works in real time with a minimum hardware add-on. • It converts the spoken utterances into text, defined into a dictionary previously.

4. Experiments to evaluate human interaction. • Two kind of voice commands have been studied: • Low Level Commands : • Connected with telerobot movements • High Level Commands : • Connected with teleoperated task

5. Low Level Command Experiments. Description • A video image with the robot end position is displayed • A point is continuously drawn over it showing the ideal robot trajectory • Trajectory quality is the average error between end robot position and last drawn point.

6. LLC - Operator Input Devices • The 3 operator input devices are: • A master-arm, • A joystick, • A voice recognition system. • All experiments have a similar level of proprioception

7. LLC - Master Arm • Master-arm has 3 dof but only 2 are used, both confined within a horizontal plane • Operator takes the M-A by the end • M-A generates position references for the teleoperated robot

8. LLC - Joystick • The joystick has 2 dof. • It generates rate references for the telerobot: • Right movements involve telerobot right speeds, and so on.

9. LLC - Voice Commands • Voice interface vocabulary is made up by 13 words: • Numbers from “1” to“12” • “STOP” • Numbers indicated robot end speeds as a clockwise direction

10. LLC - Experiment Results • X-axes represents participants • Y-axes trajectory quality • Statistical tests show: • There are not differences between operators • There are differences between input devices • Master-Arm and Joystick are similar

11. High Level Commands • Two interfaces have been evaluated: • Natural Language Procedure: • Voice commands are generated following a given imperative grammar structure • Menu: • Different options shown graphically are chosen by voice

12. HLC - Natural Lan-guage Procedure • Isolated words are recognized by the VISHA system • An imperative grammar structure is defined for the operator sentences • Semantic Analysis extracts the meaning • D.I. and P.A. obtain the command for the telerobot

13. HLC - Menu • Menu interface provides the operator with different options chosen by voice. • Articulated words active the consecutive submenus until complete the desired command

14. HLC - Results • NLP and Menu interface generate the commands whit a very different interaction. • Recognition rate is a critical factor for the operator usefulness (>95 %) • Firstly operator prefers NLP interface because it is spectacular • Then operator prefers Menu interaction because it is more straightforward and comfortable for an isolated word recognition system

15. Voice Interaction Conclusions (I) • Hand movements are the best way to guide a telerobot (LLC) • In this experiments proprioception is more important than the mode control (rate or position) • To guide a robot by voice could be attractive but it is inefficiently because orders are generated slowly

16. Voice Interaction Conclusions (II) • HLC need a lot of information from the remote environment and the executed task • Menu is the best voice interface using an isolated word recognition system

17. Applications and Future works • A menu interface by voice has been applied in telerobotic system for live line maintenance, called ROBTET • Future works: • Study differences between rate and position control guiding a telerobot • Compare NLP and Menu interfaces using a word recognition system working continuously