SCHOOL OF ENGINEERING
these applications in mind, this research focuses on control of a robotic arm using a 14-electrode EEG headset. Both pure EEG signals and electromyography (EMG) signals are encoded as controls for six possible actions performed by the robotic arm.
EEG Action Encoding
STUDENTS Theus H Aspiras, Kelly Cashion, Carly A Gross ADVISORS Vijayan K Asari LOCATION, TIME RecPlex, 11:00 AM-12:30 PM Electrical and Computer Engineering, Poster - Graduate Research The Electroencephalograms (EEGs) Action Encoding is focused on translating the EEG signals into actions such as lift, turn, grab, drop, pull, push, and so on. This research has many possible applications, but more research must be done in order to turn these ideas into a reality. It could help the handicapped use robots to complete various tasks. It could also be used to communicate with coma patients. The robots could be controlled by thoughts to accomplish tasks too dangerous for humans. In order to translate the thoughts into actions, a program will be trained to recognize patterns in the EEG that are associated with one of these actions. Multiple challenges include variations in thought patterns between people and differences in thought patterns between thinking about and actually performing an action. An appropriate plan to collect and translate the data has been formulated. The patient will be fitted with the Data Acquisition Device and their brainwaves will be collected while they perform various tasks. This data will be filtered to remove noise and eye blinks, and then used to train the program.
Bidirectional Beam Propagation Method for Second-Harmonic Generation in Engineered Multilayer Photonic Bandgap Structures
STUDENTS Han Li ADVISORS Partha P Banerjee LOCATION, TIME RecPlex, 11:00 AM-12:30 PM Electro-Optics Graduate Engineering Program, Poster - Graduate Research The transfer matrix method (TMM) has been used to analyze plane wave and beam propagation through linear photonic bandgap structures. Here, we apply TMM to determine the exact spatial behavior of TE and TM waves in periodic refractive index nonlinear structures of arbitrary thickness. First, we extend the TMM approach to analyze plane wave propagation through Kerr type nonlinear media. Secondly, In the second order nonlinearity case, the proposed TMM takes into consideration reflections and the interferences between the forward and backward-propagating waves but the nonlinear process is assumed to be weak so that the pump wave is unaffected by the nonlinear process thus the undepleted approximation. Finally in the second order nonlinearity case, the TMM is applied to study beam propagation in such media by applying the TMM to its angular spectrum components.
Nonlinearly Induced Refractive Index Measurements by Using a Probe Beam.
STUDENTS Ujitha A Abeywickrema ADVISORS Partha P Banerjee LOCATION, TIME RecPlex, 11:00 AM-12:30 PM Electro-Optics Graduate Engineering Program, Poster - Graduate Research Self phase modulation is a nonlinear effects that is observed when a laser beam is focused on to a high-absorbing thermal medium. The refractive index of the medium changes due to the heat generated by the focused laser pump beam. In this paper, self phase modulation is investigated in different ways. An Ar-Ion laser of 514 nm is used as the pump beam and a 632 nm He-Ne laser is used as the probe beam. The probe beam is introduced from the opposite side of the pump beam. Ring patterns are observed from the each side of the sample. Regular far field ring patterns are observed from the pump beam, and two sets of rings are observed with the probe beam. The behavior of these inner and outer rings are monitored for different pump powers. A regular tea sample in a plastic cuvette is used as the nonlinear absorbing sample. The steady state heat equation is solved to obtain an exact solution for the radial heat distribution and far field ring patterns are simulated using the Fresnel'Kirchhoff diffraction integral. Ring patterns are theoretically explained using simulations results, and compared with experimental observations. Finally, an interferometric setup using the low power He-Ne laser is also used to determine the induced change in refractive index. Results are compared with those obtained directly from self-phase modulation and from the probe beam method.
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