System and method that allow to jointly cause movement of multiple micro-and-nano-objects to desired positions are described. A high speed camera tracks the locations of the objects. An array of photo-transistor-controlled electrodes is used to generate a dynamic potential energy landscape for manipulating objects with both DEP and EP forces, and a video projector is used actuate the array. One or more computing devices are used to: process images captured by the camera to estimate positions of the objects; generate desired trajectories of the objects using an objective function; compare the desired chiplet positions with current positions and generate input signals to minimize the error between them; and map the control inputs to images that are projected on the array using a video project. The projected images activate or deactivate electrodes, as indicated by the control inputs.

System and method that allow to jointly cause movement of multiple micro-and-nano-objects to desired positions are described. A high speed camera tracks the locations of the objects. An array of electrodes is used to generate a dynamic potential energy landscape for manipulating objects with both DEP and EP forces. One or more computing devices are used to: process images captured by the camera to estimate positions of the objects; use model predictive control optimization to obtain trajectories and electrode potentials for moving at least some of the objects from estimated positions to further positions; and control the electrodes based on electrode potentials.

In one embodiment, a 3D printing system includes: a stage on which a substrate is disposed; first and second syringe pumps; first and second syringes; a hydrodynamic flow focusing nozzle having a central channel coupled to the first syringe to receive a printing ink and two side channels on two sides of the central channel and coupled to the second syringe to receive a sheath fluid to pinch the central channel; and a pulse generator to apply an electric potential between the hydrodynamic flow focusing nozzle and the substrate to deposit the printing ink on the substrate on-demand and control ejection frequency of the printing ink. The first syringe pump is controllable to adjust a printing ink flow rate of the printing ink to deposit the printing ink onto the substrate. The second syringe pump is controllable to adjust a sheath fluid flow rate of the sheath fluid.

Filter assemblies are disclosed. In particular, filter assemblies including a filter media and an overlay portion covering the filter media are disclosed. Such filter assemblies may provide both acceptable filtering capacity and cleanable visible front surfaces.

System and method that allow to jointly cause movement of multiple micro-and-nano-objects to desired positions are described. A high speed camera tracks the locations of the objects. An array of electrodes is used to generate a dynamic potential energy landscape for manipulating objects with both DEP and EP forces. One or more computing devices are used to: process images captured by the camera to estimate positions of the objects; use model predictive control optimization to obtain trajectories and electrode potentials for moving at least some of the objects from estimated positions to further positions; and control the electrodes based on electrode potentials.

The present invention may be configured to: apply, while maintaining a separation distance (d) between a substrate and a conductive mask, different electric potentials to each of the substrate and the mask to form an electric field due to an electric potential difference; to make charged nanoparticles pass through a hole of the mask according to the intensity of the electric field to determine the degree to which the charged nanoparticles are focused on the substrate; and control the size and shape of a three-dimensional structure formed by depositing the nanoparticles on the substrate according to the focusing degree.

In one embodiment, a 3D printing system includes: a stage on which a substrate is disposed; first and second syringe pumps; first and second syringes; a hydrodynamic flow focusing nozzle having a central channel coupled to the first syringe to receive a printing ink and two side channels on two sides of the central channel and coupled to the second syringe to receive a sheath fluid to pinch the central channel; and a pulse generator to apply an electric potential between the hydrodynamic flow focusing nozzle and the substrate to deposit the printing ink on the substrate on-demand and control ejection frequency of the printing ink. The first syringe pump is controllable to adjust a printing ink flow rate of the printing ink to deposit the printing ink onto the substrate. The second syringe pump is controllable to adjust a sheath fluid flow rate of the sheath fluid.