A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC usin...A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC using small movements of single finger. By using image processing techniques with the Web camera, the finger is appropriately detected from the images captured by it. Control boxes for pointing and text input functions are also made. To verify performances of the interface, some tasks are experimentally performed by three able-bodied subjects and a person suffering from spinal muscular atrophy. It was clear from the experimental results that all the subjects could smoothly nerforrn the t,~k~展开更多
The dexterous upper limb serves as the most important tool for astronauts to implement in-orbit experiments and operations. This study developed a simulated weightlessness experiment and invented new measuring equipme...The dexterous upper limb serves as the most important tool for astronauts to implement in-orbit experiments and operations. This study developed a simulated weightlessness experiment and invented new measuring equipment to quantitatively evaluate the muscle ability of the upper limb. Isometric maximum voluntary contractions （MVCs） and surface electromyography （sEMG） signals of right-handed pushing at the three positions were measured for eleven subjects. In order to enhance the com- prehensiveness and accuracy of muscle force assessment, the study focused on signal processing techniques. We applied a combination method, which consists of time-, frequency-, and bi-frequency- domain analyses. Time- and frequency-domain analyses estimated the root mean square （RMS） and median frequency （MDF） of sEMG signals, respectively. Higher order spectra （HOS） of bi-frequency domain evaluated the maximum bispectrum amplitude （Bmax）, Gaussianity level （Sg） and lineari- ty level （S0 of sEMG signals. Results showed that B S,, and RMS values all increased as force increased. MDF and Sg val- ues both declined as force increased. The research demonstrated that the combination method is superior to the conventional time- and frequency-domain analyses. The method not only described sEMG signal amplitude and power spectrum, but also deeper characterized phase coupling information and non-Gaussianity and non-linearity levels of sEMG, compared to two conventional analyses. The finding from the study can aid ergonomist to estimate astronaut muscle performance, so as to opti- mize in-orbit operation efficacy and minimize musculoskeletal injuries.展开更多
文摘A noncontact user interface using image processing for people with neuromuscular diseases is presented in this paper. The user interface is composed of a Web camera and a PC, and allows users to manipulate the PC using small movements of single finger. By using image processing techniques with the Web camera, the finger is appropriately detected from the images captured by it. Control boxes for pointing and text input functions are also made. To verify performances of the interface, some tasks are experimentally performed by three able-bodied subjects and a person suffering from spinal muscular atrophy. It was clear from the experimental results that all the subjects could smoothly nerforrn the t,~k~
基金supported by the National High Technology Research and Development Program of Chinathe National Basic Research Program of China(Grant No.2011CB7000)
文摘The dexterous upper limb serves as the most important tool for astronauts to implement in-orbit experiments and operations. This study developed a simulated weightlessness experiment and invented new measuring equipment to quantitatively evaluate the muscle ability of the upper limb. Isometric maximum voluntary contractions （MVCs） and surface electromyography （sEMG） signals of right-handed pushing at the three positions were measured for eleven subjects. In order to enhance the com- prehensiveness and accuracy of muscle force assessment, the study focused on signal processing techniques. We applied a combination method, which consists of time-, frequency-, and bi-frequency- domain analyses. Time- and frequency-domain analyses estimated the root mean square （RMS） and median frequency （MDF） of sEMG signals, respectively. Higher order spectra （HOS） of bi-frequency domain evaluated the maximum bispectrum amplitude （Bmax）, Gaussianity level （Sg） and lineari- ty level （S0 of sEMG signals. Results showed that B S,, and RMS values all increased as force increased. MDF and Sg val- ues both declined as force increased. The research demonstrated that the combination method is superior to the conventional time- and frequency-domain analyses. The method not only described sEMG signal amplitude and power spectrum, but also deeper characterized phase coupling information and non-Gaussianity and non-linearity levels of sEMG, compared to two conventional analyses. The finding from the study can aid ergonomist to estimate astronaut muscle performance, so as to opti- mize in-orbit operation efficacy and minimize musculoskeletal injuries.
