Design of a Ballistically-Launched Foldable Multirotor

The operation of multirotors in crowded environments requires a highly reliable takeoff method, as failures during takeoff can damage more valuable assets nearby. The addition of a ballistic launch system imposes a deterministic path for the multirotor to prevent collisions with its environment, as well as increases the multirotor’s range of operation and allows deployment from an unsteady platform. In addition, outfitting planetary rovers or entry vehicles with such deployable multirotors has the potential to greatly extend the data collection capabilities of a mission. A proof-of-concept multirotor aircraft has been developed, capable of transitioning from a ballistic launch configuration to a fully controllable flight configuration in midair after launch. The transition is accomplished via passive unfolding of the multirotor arms, triggered by a nichrome burn wire release mechanism. The design is 3D printable, launches from a three-inch diameter barrel, and has sufficient thrust to carry a significant payload. The system has been fabricated and field tested from a moving vehicle up to 50mph to successfully demonstrate the feasibility of the concept and experimentally validate the design’s aerodynamic stability and deployment reliability

Design and Autonomous Stabilization of a Ballistically Launched Multirotor

Aircraft that can launch ballistically and convert to autonomous, free flying drones have applications in many areas such as emergency response, defense, and space exploration, where they can gather critical situational data using onboard sensors. This paper presents a ballistically launched, autonomously stabilizing multirotor prototype (SQUID, Streamlined Quick Unfolding Investigation Drone) with an onboard sensor suite, autonomy pipeline, and passive aerodynamic stability. We demonstrate autonomous transition from passive to vision based, active stabilization, confirming the ability of the multirotor to autonomously stabilize after a ballistic launch in a GPS denied environment.Comment: Accepted to 2020 International Conference on Robotics and Automatio

Episodic Koopman Learning of Nonlinear Robot Dynamics with Application to Fast Multirotor Landing

This paper presents a novel episodic method to learn a robot’s nonlinear dynamics model and an increasingly optimal control sequence for a set of tasks. The method is based on the Koopman operator approach to nonlinear dynamical systems analysis, which models the flow of observables in a function space, rather than a flow in a state space. Practically, this method estimates a nonlinear diffeomorphism that lifts the dynamics to a higher dimensional space where they are linear. Efficient Model Predictive Control methods can then be applied to the lifted model. This approach allows for real time implementation in on-board hardware, with rigorous incorporation of both input and state constraints during learning. We demonstrate the method in a real-time implementation of fast multirotor landing, where the nonlinear ground effect is learned and used to improve landing speed and quality

Extended Dynamic Mode Decomposition with Learned Koopman Eigenfunctions for Prediction and Control

This paper presents a novel learning framework to construct Koopman eigenfunctions for unknown, nonlinear dynamics using data gathered from experiments. The learning framework can extract spectral information from the full non-linear dynamics by learning the eigenvalues and eigenfunctions of the associated Koopman operator. We then exploit the learned Koopman eigenfunctions to learn a lifted linear state-space model. To the best of our knowledge, our method is the first to utilize Koopman eigenfunctions as lifting functions for EDMD-based methods. We demonstrate the performance of the framework in state prediction and closed loop trajectory tracking of a simulated cart pole system. Our method is able to significantly improve the controller performance while relying on linear control methods to do nonlinear control

Design and Autonomous Stabilization of a Ballistically-Launched Multirotor

Aircraft that can launch ballistically and convert to autonomous, free-flying drones have applications in many areas such as emergency response, defense, and space exploration, where they can gather critical situational data using onboard sensors. This paper presents a ballistically-launched, autonomously-stabilizing multirotor prototype (SQUID - Streamlined Quick Unfolding Investigation Drone) with an onboard sensor suite, autonomy pipeline, and passive aerodynamic stability. We demonstrate autonomous transition from passive to vision-based, active stabilization, confirming the multirotor’s ability to autonomously stabilize after a ballistic launch in a GPS-denied environment

Design and Autonomous Stabilization of a Ballistically-Launched Multirotor

Aircraft that can launch ballistically and convert to autonomous, free-flying drones have applications in many areas such as emergency response, defense, and space exploration, where they can gather critical situational data using onboard sensors. This paper presents a ballistically-launched, autonomously-stabilizing multirotor prototype (SQUID - Streamlined Quick Unfolding Investigation Drone) with an onboard sensor suite, autonomy pipeline, and passive aerodynamic stability. We demonstrate autonomous transition from passive to vision-based, active stabilization, confirming the multirotor’s ability to autonomously stabilize after a ballistic launch in a GPS-denied environment

Improving levodopa delivery: IPX203, a novel extended-release carbidopa-levodopa formulation.

INTRODUCTION: IPX203 is a novel oral extended-release (ER) formulation of carbidopa (CD) and levodopa (LD) developed to address the short half-life and limited area for absorption of LD in the gastrointestinal tract. This paper presents the formulation strategy of IPX203 and its relationship to the pharmacokinetics (PK) and pharmacodynamic profile of IPX203 in Parkinson\u27s disease (PD) patients. METHODS: IPX203 was developed with an innovative technology containing immediate-release (IR) granules and ER beads that provides rapid LD absorption to achieve desired plasma concentration and maintaining it within the therapeutic range for longer than can be achieved with current oral LD formulations. The PK and pharmacodynamics of IPX203 were compared with IR CD-LD in a Phase 2, open-label, rater-blinded, multicenter, crossover study in patients with advanced PD. RESULTS: Pharmacokinetic data showed that on Day 15, LD concentrations were sustained above 50% of peak for 6.2 h with IPX203 vs. 3.9 h with IR CD-LD (P = 0.0002). Pharmacodynamic analysis demonstrated that mean MDS-UPDRS Part III scores prior to administration of the first daily dose were significantly lower among patients receiving IPX203 than IR CD-LD (LS mean difference –8.1 [25.0], P = 0.0255). In a study conducted in healthy volunteers, a high-fat, high-calorie meal delayed plasma LD Tmax by 2 h, and increased Cmax and AUCtau by approximately 20% compared with a fasted state. Sprinkling capsule contents on applesauce did not affect PK parameters. CONCLUSION: These data confirm that the unique design of IPX203 addresses some of the limitations of oral LD delivery

Analysis of the spectra of trivalent erbium in multiple sites of hexagonal aluminum nitride

The 12 K cathodoluminescence spectra of Er3+ doped into single crystals of aluminum nitride (2H-AlN) in the hexagonal phase are reported between 320 nm and 775 nm. The emission spectra represent transitions from the lower Stark level of 2P(3/2) to the Stark levels of the 4I(15/2), 4I(13/2), 4I(11/2), 4I(9/2), 4F(9/2), and 4S(3/2) multiplet manifolds of Er3+(4f(11)). Emission spectra from 4S(3/2) to 4I(15/2) are also reported. All observed strong line emission are accounted for in terms of two principle sites, denoted site a and site b , with a few line spectra attributed to additional sites. A parameterized Hamiltonian that includes the atomic and crystal-field terms for Er3+(4f(11)) (2S+1)L_J was used to determine the symmetry and the crystal field splitting of the a and b sites. A descent in symmetry calculation was carried out to determine if distortion due to the size difference between Er, Al and the vacancies can be discerned. Modeling results assuming C_3v and C_1h are discussed. It appears that the sensitivity to a C_1h model is not sufficient to invalidate the choice of C_3v as an approximate symmetry for both sites. The g-factors reported from an EPR study of Er3+ in single-crystal AlN are in reasonable agreement with calculated g-factors for Er3+ in the a site assuming C_3v symmetry

Practice Guidelines for Teledermatology

Previous American Telemedicine Association (ATA) Teledermatology Practice Guidelines were issued in 2007. This updated version reflects new knowledge in the field, new technologies, and the need to incorporate teledermatology practice in a variety of settings, including hospitals, urgent care centers, Federally Qualified Health Centers, school-based clinics, public health facilities, and patient homes.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140294/1/tmj.2016.0137.pd