• 제어로봇시스템학회논문지
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• 제12권6호
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• pp.568-572
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• 2006

This paper presents the device of recognizing image of the studded paving blocks, transmitting, the information by vibration to a visually handicapped person. Usually the blind uses the walking stick to recognize the studded paving block. This research uses a PCA (Principal Component Analysis) based image processing approach for recognizing the paving blocks. We classify the studded paving blocks into 5 classes, that is, vertical line block, right-declined line block, left-declined line block, dotted block and flat block. The 8 images for each of 5 classes are captured for each block by 112*120 pixels, then the eigenvectors are obtained in magnitude order of eigenvectors by using principal component analysis. The principal components for images can be calculated using projection of transformation matrix composed of eigenvectors. The classification has been executed using Euclidean's distance, so the block having minimum distance with a image is chosen as matched one. The result of classification is transmitted to the blind by electric vibration signals with different magnitudes and frequencies.

• 대한족부족관절학회지
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• 제22권3호
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• pp.100-104
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• 2018

Purpose: An axillary crutch is the most commonly used assistive device in foot and ankle patients who require nonweightbearing. On the other hand, its use frequently induces axillary or wrist pain and critical neurovascular injuries have been reported in several studies. This study compared the clinical outcomes of patients using the knee walker and axillary crutch. Materials and Methods: A retrospective analysis was performed comparing the utility of a knee walker and axillary crutch as a nonweightbearing ambulatory aid for 62 foot and ankle patients treated between November 2016 and March 2018. A comparative study of the two orthosis could be performed because all the patients temporarily used an axillary crutch before or after the use of a knee walker. A demographic study and comparative analysis based on the visual analogue scale (VAS) satisfaction score (0~100), complications, and fall down history were evaluated. Furthermore, under the assumption of having retreatment, their preference of orthosis between the knee walker and axillary crutch was investigated. Results: The mean age of the patients was 36.5 and the mean duration of ambulation with a knee walker and axillary crutch were 5.2 and 2.4 weeks. The VAS satisfaction score of the knee walker and crutch was 88.8 and 27.5, respectively (p<0.05). The most frequent complications of the knee walker and crutch were ipsilateral knee pain (6 cases) and axillary or wrist pain (56 cases), respectively. No case of falling down occurred during knee walker ambulation, but there were two cases of crutch ambulation. Fifty-eight patients (93.5%) preferred the knee walker and four patients (6.5%) preferred a crutch. Conclusion: Compared to the axillary crutch, the knee walker afforded lower complication and higher satisfaction. Most patients preferred the knee walker to a crutch. Therefore, the knee walker is an efficient and safe orthosis for foot and ankle patients who require nonweightbearing.