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