This study investigated the effect of palate morphology and anthropometric measures of the head and face on lingual consonant target (positional) variability of twenty one adult speakers (eleven male, ten female). An electromagnetic tracking system (WAVE, NDI, Canada) was used to collect tongue movements while each speaker produced a series of VCV syllables containing a combination of consonants /t, d, s, z, ʃ, tʃ, k, g, j/ and three corner vowel /i, ɑ, u/. Distributions of x, y, and z coordinates representing maximum tongue elevation during the consonants were used to represent target variability across contexts. Palate and anthropometric measures were obtained for each participant. A correlational analysis showed that target variability of the consonants produced in the front of the mouth (e.g. alveolar and palatal) was explained, to a degree, by palate morphology. The variability of velar consonants was not explained by the structural measures.

Trunk instability is a major problem for people with spinal cord injury (SCI); it not only limits their independence, but also leads to secondary health complications such as kyphosis, pressure sores, and respiratory dysfunction. In exploring mechanisms that may facilitate or compromise postural stability, dynamic models are very useful because the spine dynamics are difficult to study in vivo compared to other structures of the body. Therefore, one objective of this work was to develop a detailed three-dimensional dynamic model of the human trunk as a tool for investigating the neural-mechanical control strategy that healthy people apply to maintain trunk stability during various tasks. Since trunk control is fairly complex, however, another objective of this work was to provide insights into the balance control strategy of a simpler neuro-musculo-skeletal system that may facilitate future studies on trunk control. For this purpose, the control of the ankle joint complex during quiet standing (anterior-posterior degree of freedom) was studied in place of the trunk. The obtained results reveal that a neural-mechanical control scheme using a proportional-derivative controller as the neural control strategy can overcome a large sensory-motor (feedback) time delay and stabilize the ankle joint during quiet standing. Moreover, a detailed dynamic model of the trunk has been developed that is: (1) based on highly accurate geometric models; and (2) universally applicable. Thus, this work also responds to the postulation that structurally more complex models are needed to better characterize the biomechanics of multifaceted systems. Combining the developed biomechanical tools for the trunk with the postural control insights for the ankle joint during standing will be beneficial for: (1) understanding the neural-mechanical control strategy that facilitates trunk stability in healthy people; and for (2) developing neuroprostheses for trunk stability after SCI and other neurological disorders.

Trunk instability is a major problem for people with spinal cord injury (SCI); it not only limits their independence, but also leads to secondary health complications such as kyphosis, pressure sores, and respiratory dysfunction. In exploring mechanisms that may facilitate or compromise postural stability, dynamic models are very useful because the spine dynamics are difficult to study in vivo compared to other structures of the body. Therefore, one objective of this work was to develop a detailed three-dimensional dynamic model of the human trunk as a tool for investigating the neural-mechanical control strategy that healthy people apply to maintain trunk stability during various tasks. Since trunk control is fairly complex, however, another objective of this work was to provide insights into the balance control strategy of a simpler neuro-musculo-skeletal system that may facilitate future studies on trunk control. For this purpose, the control of the ankle joint complex during quiet standing (anterior-posterior degree of freedom) was studied in place of the trunk. The obtained results reveal that a neural-mechanical control scheme using a proportional-derivative controller as the neural control strategy can overcome a large sensory-motor (feedback) time delay and stabilize the ankle joint during quiet standing. Moreover, a detailed dynamic model of the trunk has been developed that is: (1) based on highly accurate geometric models; and (2) universally applicable. Thus, this work also responds to the postulation that structurally more complex models are needed to better characterize the biomechanics of multifaceted systems. Combining the developed biomechanical tools for the trunk with the postural control insights for the ankle joint during standing will be beneficial for: (1) understanding the neural-mechanical control strategy that facilitates trunk stability in healthy people; and for (2) developing neuroprostheses for trunk stability after SCI and other neurological disorders.

The demand of modern technology is highly required by humans. The Linear motor, one of the most significant inventions, has been playing a vital role in driving component. The Structure of the gantry is the main design and the requirement of high bandwidth and rigidity. Twin-linear motors coupled and paralleled with machining beam are to realize one degree-movement. To prevent the marching beam from deformation, the synchronized motion control becomes an important technology for this machine. This thesis solves the problem of the mechanism coupling by using of the synchronized master command approach which integrates the decouple control and internal model control and taking the mechanism beam as an uncertainty. Both system uncertainties and unknown disturbances occurring in actual implementation need to be carefully considered. And the synchronized motion control of the two linear servo systems with mechanism will be investigated. Better synchronization performance for two motors can therefore be anticipated.

Coordinated or synchronized tasks can always be found in various manufacturing processes, e.g., machining along spatial trajectories, coordinated operations of multi-manipulators, and vacuum pumps, etc. The vacuum pump is a typical device with synchronized motion among those examples. The vacuum pump has played an important role in current semiconductor manufacturing processes. Its pumping feature is achieved by synchronized motion of two mating pump rotors. A common approach to accomplish the synchronized motion is by idle gears. Nevertheless, this design cannot meet serious requirements of vacuum systems demanded by growing manufacturing techniques. In order to provide a complete and proper control strategy for synchronized motion, and to overthrow traditional architecture of vacuum pumps by raising a better control scheme for new generation oil-less products, the paper focuses on synchronized motion control for dual motors. The first objective of here is to develop a control method for synchronized motion of two separated motors. Both system uncertainties and unknown disturbances occurring in actual implementation need to be carefully considered. An experimental setup will also be established for examinations and verifications. And then synchronized motion control of dual motors including two mating screw rotors then will be investigated. During this period, the emphasis will be on solution finding for unexpected contact collision between two rotors. An effective and efficient control strategy will be developed for synchronized motion control of dual motors. Longer operation time and better synchronization performance for two motors can therefore be anticipated.

Abstract Coordinated or synchronized tasks can always be found in various manufacturing processes, e.g., machining along spatial trajectories, coordinated operations of multi-manipulators, and vacuum pumps, etc. The vacuum pump is a typical device with synchronized motion among those examples. The vacuum pump has played an important role in current semiconductor manufacturing processes. Its pumping feature is achieved by synchronized motion of two mating pump rotors. A common approach to accomplish the synchronized motion is by idle gears. Nevertheless, this design cannot meet serious requirements of vacuum systems demanded by growing manufacturing techniques. In order to provide a complete and proper control strategy for synchronized motion, and to overthrow traditional architecture of vacuum pumps by raising a better control scheme for new generation oil-less products, the paper focuses on synchronized motion control for dual motors. The first objective of here is to develop a control method for synchronized motion of two separated motors. Both system uncertainties and unknown disturbances occurring in actual implementation need to be carefully considered. An experimental setup will also be established for examinations and verifications. And then synchronized motion control of dual motors including two mating screw rotors then will be investigated. During this period, the emphasis will be on solution finding for unexpected contact collision between two rotors. An effective and efficient control strategy will be developed for synchronized motion control of dual motors. Longer operation time and better synchronization performance for two motors can therefore be anticipated.

Studies of static and dynamic motor control have a long research history. In most cases, studies have focused on one condition or the other. However, it is important to determine whether differences exist between the two types of task, especially when used in conjunction with task performance. Video game controllers, motorized wheel chairs, steering wheels, and robotic surgical equipment are all examples of how modern equipment uses static and dynamic motor control to achieve task performance goals. To this end, this study aimed to examine possible differences in accuracy or consistency of performance between static and dynamic variations of a precision fine motor tracking task. Nineteen healthy, right-handed volunteer participants were asked to manipulate a cursor to track a moving target with both index fingers, using a static control method in one task and a dynamic control method in another task. The cursor was to follow as closely as possible a target traveling along a diagonal line and back. The control methods were tested during two different testing sessions to reduce confounding of the task conditions. After 50 practice trials in a condition, 5 test trials were recorded. Two dependent variables, RMSE and CVE, were used to represent task performance as indicators of accuracy and consistency, respectively. Analyses of variance with a Latin Square design were used to compare overall performance of each dependent variable between the two conditions. Results showed a significant difference in both variables with p-values less than .001; tracking accuracy was better on the static task and cursor motion consistency was better on the dynamic task. These findings suggest that performance aspects of a fine motor control task does vary with control method and can be used to aid equipment design and task performance in the future. / text

This report will review critically the available research on deep brain stimulation and levodopa as a means of treatment for Parkinson’s disease in an attempt to determine why neither of these treatments improves speech. / text

This thesis presents evidence from a formant perturbation experiment which supports the hypothesis that speech targets are multimodal. A real-time auditory feedback perturbation is used to gradually shift English speakers' formants from the vowel /E/ towards /I/. Most speakers compensate at the level of acoustics, adjusting their production towards /ae/ such that they hear themselves producing the correct vowel. Subjects' articulation is tracked with electromagnetic-articulography. The articulatory data shows that subjects tend to produce marginal /E/s at the level of articulation - remaining within the normal articulatory bounds for that vowel, while adjusting the position of individual articulators to a sufficient extent to create an acoustic compensation to the perturbation. The higher-order relationship between speed and curvature is shown to differ across different vowel phonemes. However, this measure remains constant under formant perturbation. These findings are argued to show that phonemic targets are multi-modal, having acoustical, kinematic, and dynamic components.

This thesis presents evidence from a formant perturbation experiment which supports the hypothesis that speech targets are multimodal. A real-time auditory feedback perturbation is used to gradually shift English speakers' formants from the vowel /E/ towards /I/. Most speakers compensate at the level of acoustics, adjusting their production towards /ae/ such that they hear themselves producing the correct vowel. Subjects' articulation is tracked with electromagnetic-articulography. The articulatory data shows that subjects tend to produce marginal /E/s at the level of articulation - remaining within the normal articulatory bounds for that vowel, while adjusting the position of individual articulators to a sufficient extent to create an acoustic compensation to the perturbation. The higher-order relationship between speed and curvature is shown to differ across different vowel phonemes. However, this measure remains constant under formant perturbation. These findings are argued to show that phonemic targets are multi-modal, having acoustical, kinematic, and dynamic components.