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Electrically evoked compound action potentials (ECAPs) generated in the subthalamic nucleus (STN) contain features that may be useful for titrating deep brain stimulation (DBS) therapy for Parkinson’s disease. Delivering a strong therapeutic effect with DBS therapies, however, relies on selectively targeting neural pathways to avoid inducing side effects. In this study, we investigated the spatiotemporal features of ECAPs in and around the STN across parameter sweeps of stimulation current amplitude, pulse width, and electrode configuration, and used a linear classifier of ECAP responses to predict electrode location. Four non-human primates were implanted unilaterally with either a directional (n = 3) or non-directional (n = 1) DBS lead targeting the sensorimotor STN. ECAP responses were characterized by primary features (within 1.6 ms after a stimulus pulse) and secondary features (between 1.6 and 7.4 ms after a stimulus pulse). Using these features, a linear classifier was able to accurately differentiate electrodes within the STN versus dorsal to the STN in all four subjects. ECAP responses varied systematically with recording and stimulating electrode locations, which provides a subject-specific neuroanatomical basis for selecting electrode configurations in the treatment of Parkinson’s disease with DBS therapy.

Conventional wind turbines are equipped with multi-stage fixed-ratio gearboxes to transmit power from the low speed rotor to the high speed generator. Gearbox failure is a major issue causing high maintenance costs. With a superior power to weight ratio, a hydrostatic transmission (HST) is an ideal candidate for a wind turbine drivetrain. HST, a continuous variable transmission, has the advantage of delivering high power with a fast and accurate response. To evaluate the performance of the HST wind turbine, a power regenerative hydrostatic wind turbine test platform has been developed. A hydraulic power source is used to emulate the dynamics of the turbine rotor. The test platform is an effective tools to validate the control strategies of the HST wind turbine. This paper presents the high fidelity mathematical model of the test platform. The parameters of the dynamic equations are identified by the experiments. The steady state and transient operations results are compared with the experimental data. The detailed control architecture of the start-up and shut-down cycle is described for the test platform.