Abstract: A method for direct write printing of an electrical or optical element based upon a generated master actual position map and a master expected position map is disclosed. The generated master actual position map is generated by efficiently stitching together a number of images using a hierarchical stitching process. Once the desired location of the electrical or optical element is determined by comparing the master actual position map with the master expected position map, a corresponding toolpath for a direct write printer is generated. The direct write printer then direct write prints the electrical or optical element using the generated toolpath. By using different types of inks, the electrical element may be a trace, a resistor, an inductor, a transformer, a capacitor, or some combination thereof. In like manner, the optical element may be a waveguide, a beam-splitter, a phase shifter, an optical attenuator, an interferometer, or some combination thereof.

Abstract: A capacitive soil moisture sensor for detecting moisture levels in soil comprises a biodegradable substrate. A capacitive circuit is positioned on the biodegradable substrate. An antenna circuit is configured to communicate capacitance data. A hydrophobic, biodegradable encapsulating material encases at least the capacitive circuit.

Abstract: A method for directly writing metal traces on a wide range of substrate materials is disclosed. The method includes writing a pattern of particle-free metal-salt-based ink on the substrate followed by a plasma-based treatment to remove the non-metallic components of the ink and decompose its metal salt into pure metal. The ink is based on a multi-part solvent whose components differ in at least one of evaporation rate, surface tension, and viscosity, which improves the manner in which the ink is converted into its metal constituent via the plasma treatment. In some embodiments, a microplasma is used for post-treatment of the deposited ink, where the plasma properties are controlled to provide different material properties, such as porosity and effective resistivity, in different regions of the metal pattern.

Abstract: A method for directly writing metal traces on a wide range of substrate materials is disclosed. The method includes writing a pattern of particle-free metal-salt-based ink on the substrate followed by a plasma-based treatment to remove the non-metallic components of the ink and decompose its metal salt into pure metal. The ink is based on a multi-part solvent whose components differ in at least one of evaporation rate, surface tension, and viscosity, which improves the manner in which the ink is converted into its metal constituent via the plasma treatment. In some embodiments, a microplasma is used for post-treatment of the deposited ink, where the plasma properties are controlled to provide different material properties, such as porosity and effective resistivity, in different regions of the metal pattern.