IMEKO Event Proceedings Search

   

Page 890 of 936 Results 8891 - 8900 of 9356

Pietro G. Morasso, Maura Casadio, Cristina Re, Vittorio Sanguineti
MOTOR CONTROL MECHANISMS IN UNSTABLE TASKS

The motor control mechanisms adopted by humans when carrying out unstable tasks are investigated in relation with 2 specific paradigms: A) Stabilisation of the standing posture; B) Stabilisation of an inverted pendulum, grasped at different heights. It is shown that stiffness control is present but is insufficient and predictive control mechanisms are filling the gap.

Francesco Crenna, Matteo Panero, Giovanni B. Rossi
EVALUATION OF THE SOUND EMITTED BY POST-SORTING MACHINES WITH JURY TEST METHODS

Ergonomics aspects in working environment have grown the awareness of the need of improving sound quality of machinery sound as well as to reduce its sound. Psychoacoustics supplies important tools (with more sophisticated methods employing ear–related metrics) in order to evaluate the sound quality. It is well recognized that jury (or panel) evaluation provides a reasonable guide to value the quality of machinery noise in working environment. The following work belongs to a project dealing with the studies and the applications of psychoacoustic methods in order to evaluate the sound emitted by post–sorting machines. After a measurement campaign, two kinds of jury tests have been performed, one based on pair comparison forced-choice trials, the other on magnitude estimation. The results allowed us to define a robust scale of pleasantness of typical sounds generated in a wide variety of post–sorting machines, in different environments and under different operating conditions.

Takashi Moriyama, Toshihiro Miyagawa, Shunsuke Fujiwara
TRANSIENT RESPONSE OF HUMAN BRAIN

This aim of the study is the improvement of the relationship between the operators and robotics in CIM room, and teahing room and students. It is said that we human beings are controlled by the left brain for the intelligent quality (IQ) and by the right brain for the emotional quality (EQ). The blood pressure and frequency, the face temperature and 1/f music taste and odor, the several music are supplied for alpha1 waves (8-10 Hz for the reluxation) and alpha2 waves (10-13 Hz for the concentration). Changing the tacct time of the testee’s liking suitable music is better for making tha alpha1 waves and the alpha2 waves for the right brain. For example changing Allegro (133 c/min) to Andante (70 c/min) of Mozart’s Piano Concert No.21, K 467 or Mendelssohn’s Concert for violin and orchestra in E minor, Op.64 ior Tchaikovsky’s Concert for violin and orchestra in D major, Op.35 is suitable making alpha1 and alpha2 waves in the right brain.

Ken Ohta, Mikhail Svinin, ZhiWei Luo, Shigeyuki Hosoe
DEALING WITH CONSTRAINTS: OPTIMAL TRAJECTORIES OF THE CONSTRAINED HUMAN ARM MOVEMENTS

Opening a door, turning a steering wheel, rotating a coffee mill are typical examples of human movements that require physical interaction with external environment. In these tasks, the human arm is kinematically constrained by the external environment. Although there are infinite possibilities for human subject to select his/her arm trajectories as well as interacting forces, experimental data of human constrained motion show that there exists some regulation inherent in all the measurement data. It is suggested in this paper that in the constrained movements human optimizes the criterion that minimizes the change of the hand contact forces as well as the muscle forces. This criterion differs from the minimum torque change criterion, predicting unconstrained reaching movements. Our experiments show close matching between the prediction and the subjects' data. Therefore, human may use different optimization strategies when performing constrained movements.

Douglas M. Shiller, David J. Ostry
CONTROL OF MECHANICAL IMPEDANCE IN THE OROFACIAL SYSTEM

Studies of arm movement have suggested that the control of stiffness may be important for maintaining stability during interactions with the environment. Here we have examined the voluntary control of stiffness in the human jaw. The goal was to determine whether changes in jaw stiffness might be used to maintain jaw position in the face potentially destabilizing mechanical loads. A series of force pulses was applied to the jaw using a robotic device. The loads were designed to disrupt the ability of subjects to maintain a static jaw posture. In all cases, subjects increased the magnitude of jaw stiffness in order to maintain jaw position. A clear effect of the magnitude of the destabilizing load was observed — greater increases in stiffness were observed when larger forces were applied. Moreover, subjects were able to differentially modify stiffness in the direction of the destabilizing load in the case of loads in the vertical direction. The observed change in the relative magnitude of stiffness in different directions indicates some ability to control the pattern of stiffness of the jaw. The results indicate that jaw stiffness can be adjusted voluntarily, and thus may play a role in maintaining stability. Stiffness regulations may similarly provide a means to achieve the differential precision requirements of speech.

Ksenia Sapozhnikova, Roald Taymanov
ABOUT A MEASURING MODEL OF EMOTIONAL PERCEPTION OF MUSIC

The problem of finding the parameters of musical composition, which cause emotional perception of music and at that, can be measured, has been formulated. A hypothesis has been advanced and proved under which the perception of music is realized in an inertial nonlinear system, the emotional reaction of a listener depending on the parameters of a combinative spectrum.
The regularities have been discovered which distinguish the combinative spectrum of oscillations at the output of the non-linear system under the influence of music components written in various major and minor keys.
The regularities discovered are important for psychotherapy, biophysics and science of art and can be used for developing new musical instruments.

Jukka Lekkala, Jussi Tuppurainen, Mika Paajanen
MATERIAL AND OPERATIONAL PROPERTIES OF LARGE-AREA MEMBRANE TYPE SENSORS FOR SMART ENVIRONMENTS

Certain plastic film materials can be used as sensitive tactile and impact sensors covering large surfaces. In surveillance and health care applications they can sense movement, activity or some physiological parameters. Various available film materials and their operational principles are reviewed. Comparison has been made between piezoelectric polymer film, thin porous electret material, and soft capacitive film materials in their sensing capabilities. Generation of the signal and measurement instrumentation for different sensor configurations is discussed. The structure and properties of a voided polypropylene film material and some applications and measurement results are presented. It can be shown that especially in large area applications the electret type porous films show several benefits when compared with the other solutions.

Koji Ito, Mikiko Hori, Toshio Kondo
THE IMPEDANCE AND POSITION CONTROL OF THE ROBOT MANIPULATOR BY THE EMG SIGNAL

The present paper proposes a human interface regulating the viscoelastic characteristics of the robot manipulator by the EMG signals picked up from the subject. The desired trajectory intended by the subject is generated through the bilinear internal arm model with the EMG input signals, and then the viscoelastic coefficients of robot manipulator are regulated corresponding to the sum of the flexor and extensor EMG levels. It is then shown that the subject is able to change the interactive characteristics against the robot’s environment by his own intention.

Tomáš Dresler, Jan Holub, Radislav Šmíd
VOICE TRANSMISSION QUALITY MEASUREMENT BASED ON WAVELET TRANSFORMATION

A new method for objective voice quality measurements is described in the article. It is based on wavelet transformation that enables intrinsically also time localisation of eventual impairments. In comparison with other methods (based on P.861 and P.862 algorithms), the described method saves about one half of operations needed for achievement of comparable results, thus saving computation power and time.

Isamu Kajitani, Nobuyuki Otsu, Tetsuya Higuchi
IMPROVEMENT OF MYOELECTRIC PATTERN CLASSIFICATION RATE WITH µ-LAW QUANTIZATION.

In order to realize a myoelectric-controlled multi-functional hand prosthesis, this paper proposes a method to improve the myoelectric pattern classification ability of a hand controller. By applying the proposed method of µ-LAW quantization, the pattern classification rate increased by 11.1% (averaged for five subjects) and by 15.5% (maximum), with a practical pattern classification rate of 97.8% being achieved.

Page 890 of 936 Results 8891 - 8900 of 9356