This study describes a method for performing transient finite element analysis (FEA) of an assistive device using experimental parameters obtained from gait analysis. A subject displaying pathologic gait, owing to lower limb deformity, was chosen for gait study. Using CAD tools, a remedial orthotic device was designed, which is expected to improve the gait of the subject. The orthotic model was subjected to static and transient loading conditions obtained from gait study, using an FEA tool. The stress ‘hot’ zones between the two modes of analysis are studied. In addition, the experimental gait data of a healthy control group were recorded to perform univariate regression studies for predicting the peak values of the normal forces, and validated by comparing with those available in the literature. The values thus obtained may be used for static behavioral analysis of assistive devices. From the FEA results, it can be conclusively said that the orthotic model is capable of sustaining gait cycle loading. The regression studies suggest the possibility of using anthropometric data to predict gait forces and subsequently perform static and transient loading analysis of assistive devices.

Cleft lip and palate (CLP) is a congenital disorder of the orofacial region. Nasal air emission (NAE) in CLP speech occurs due to the presence of velopharyngeal dysfunction (VPD), and it mostly occurs in the production of fricative sounds. The objective of present work is to study the acoustic characteristics of voiceless sibilant fricatives in Kannada distorted by NAE and develop an SVM-based classification to distinguish normal fricatives from the NAE distorted fricatives. Static spectral measures, such as spectral moments are used to analyze the deviant spectral distribution of NAE distorted fricatives. As the aerodynamic parameters are deviated due to VPD, the temporal variation of spectral characteristics might also get deviated in NAE distorted fricatives. This variation is studied using the peak equivalent rectangular bandwidth (ERBN)-number, a psychoacoustic measure to analyze the temporal variation in the spectral properties of fricatives. The analysis of NAE distorted fricatives shows that the maximum spectral density is concentrated in the lower frequency range with steep positive skewness and more variations in the trajectories of peak ERBN-number as compared to the normal fricatives. The proposed SVM-based classification achieves good detection rates in discriminating NAE distorted fricatives from normal fricatives.

The cleft of the lip and palate (CLP) caused by structural and functional deformation leads to various speech-related disorders, which substantially degrades the speech intelligibility. In this work, devoiced stop consonants in CLP speech are analyzed, and an approach is proposed for its modification in order to enhance the speech intelligibility. The devoicing errors are primarily characterized by the absence of voicebar in the closure interval and relatively longer voice onset time (VOT). The proposed approach first segments the regions corresponding to the closure interval and VOT based on the knowledge of glottal activity, voice onset point, voice offset point, and burst onset point. In the next stage, specific transformations are performed for the modification of closure bar and VOT respectively. For transformation, first different transformation matrices are learned for closure bar and VOT from normal and CLP speakers. The transformation matrix is optimized using nonnegative matrix factorization method. Further, the corresponding transformation matrices are used to modify the closure bar and VOT separately. The subjective evaluation results indicate that the devoiced stop consonants tend to exhibit the characteristics of voiced stop consonants.

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