Orientation control and nonlinear trajectory tracking of colloidal particles using microfluidics
arXiv:1907.08567 · doi:10.1103/PhysRevFluids.4.114203
Abstract
Suspensions of anisotropic Brownian particles are commonly encountered in a wide array of applications such as drug delivery and manufacturing of fiber-reinforced composites. Technological applications and fundamental studies of small anisotropic particles critically require precise control of particle orientation over defined trajectories and paths. In this work, we demonstrate robust control over the two-dimensional (2D) center-of-mass position and orientation of anisotropic Brownian particles using only fluid flow. We implement a path-following model predictive control scheme to manipulate colloidal particles over defined trajectories in position space, where the speed of movement along the path is a degree of freedom in the controller design. We further explore how the external flow field affects the orientation dynamics of anisotropic particles in steady and transient extensional flow using a combination of experiments and analytical modeling. Overall, this technique offers new avenues for fundamental studies of anisotropic colloidal particles using only fluid flow, without the need for external electric or optical fields.
arXiv comment12 pages, 10 figures
References in corpus (3)
Cited by in corpus (7)
- Microscale investigation of binary droplet coalescence using a microfluidic hydrodynamic trap
- Flow topology during multiplexed particle manipulation using a Stokes Trap
- Double-mode relaxation of highly deformed vesicles
- Vesicle dynamics in large amplitude oscillatory extensional flow
- Chemical herding as a multiplicative factor for top-down manipulation of colloids
- Trajectory control using an information engine
- Controlled particle displacement by hydrodynamic obstacle interaction in non-inertial flows