5,613 research outputs found
Continuum Deformation of a Multiple Quadcopter Payload Delivery Team without Inter-Agent Communication
This paper proposes continuum deformation as a strategy for controlling the
collective motion of a multiple quadcopter system (MQS) carrying a common
payload. Continuum deformation allows expansion and contraction of inter-agent
distances in a 2D motion plane to follow desired motions of three team leaders.
The remaining quadcopter followers establish the desired continuum deformation
only by knowing leaders positions at desired sample time waypoints without the
need for inter-agent communication over the intermediate intervals. Each
quadcopter applies a linear-quadratic-Gaussian (LQG) controller to track the
desired trajectory given by the continuum deformation in the presence of
disturbance and measurement noise. Results of simulated cooperative aerial
payload transport in the presence of uncertainty illustrate the application of
continuum deformation for coordinated transport through a narrow channel
Electric-field-driven polymer entry into asymmetric nanoscale channels
The electric-field-driven entry process of flexible charged polymers such as
single stranded DNA (ssDNA) into asymmetric nanoscale channels such as
alpha-hemolysin protein channel is studied theoretically and using molecular
dynamics simulations. Dependence of the height of the free-energy barrier on
the polymer length, the strength of the applied electric field and the channel
entrance geometry is investigated. It is shown that the squeezing effect of the
driving field on the polymer and the lateral confinement of the polymer before
its entry to the channel crucially affect the barrier height and its dependence
on the system parameters. The attempt frequency of the polymer for passing the
channel is also discussed. Our theoretical and simulation results support each
other and describe related data sets of polymer translocation experiments
through the alpha-hemolysin protein channel reasonably well
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