Abstract: A self-folding machine comprises a laminate including a flexible layer with a first side and a second side; a first rigid layer including at least one gap laminated to the first side of the flexible layer; a second rigid layer including at least one gap laminated to the second side of the flexible layer, wherein the rigid layers are more rigid than the flexible layer; a first contractible layer laminated to the first rigid layer and extending across at least one gap in the first rigid layer; and a second contractible layer laminated to the second rigid layer and extending across at least one gap in the second rigid layer, wherein the first and second contractible layers retract to respectively create folds in the machine across gaps in the first and second rigid layers when activated.

Abstract: Self-regulating pressure source. The pressure source includes a chamber enclosing a chemical monopropellant. A moveable boss is attached to a deformable membrane sealing an air chamber, the moveable boss and air chamber being disposed within the chamber. A catalyst is disposed around the membrane so as to be covered by the boss in a retracted position so that the monopropellant is broken down by the catalyst to produce a gas. The gas pressure will increase within the chamber causing air in the air chamber to compress thereby to pull the boss into the retracted position to cover the catalyst thereby to regulate the pressure within the chamber. The self-regulating pressure source is particularly suited to power fluidic elastomeric actuators.

Abstract: A method of optical underwater communications comprises applying a Fountain code to a plurality of data blocks. A sequence of optical data packets is transmitted through an underwater communications channel. Each optical data packet comprises one of the plurality of data blocks preceded by a preamble. The sequence of optical data packets transmitted through the underwater communication channel is received to generate a sequence of received data packets. The sequence of received data packets is sampled with the sampling clock to recover the plurality of data blocks.

Abstract: A modular robotic system that includes a plurality of self-configuring robots. Each self-configuring robot includes a frame structure having a plurality of cylindrical bonding magnets positioned along the edges of the frame structure. The frame structure includes magnetic, non-gendered, hinges on any of the edges of the frame. The hinges provide enough force to maintain a pivot axis through various motions. The cylindrical bonding magnets are free to rotate allowing for multiple self-configurations with other like self-configuring robots. A movement generator is positioned within the frame structure that pivots to generate multi-axis movement allowing both robust self-reconfiguration with the other self-configuring robots and independent locomotion.

Abstract: A method of optical underwater communications comprises applying a Fountain code to a plurality of data blocks. A sequence of optical data packets is transmitted through an underwater communications channel. Each optical data packet comprises one of the plurality of data blocks preceded by a preamble. The sequence of optical data packets transmitted through the underwater communication channel is received to generate a sequence of received data packets. The sequence of received data packets is sampled with the sampling clock to recover the plurality of data blocks.

Abstract: A flexible unit-cell actuator includes a shape memory alloy sheet having a fold between adjacent legs in one state and a heat source that upon activation concentrates heating of the shape memory alloy sheet at the fold relative to the legs to change the fold between one state and another state. The heat source may include resistive heating due to an electric current passing through the shape memory alloy sheet. The fold typically includes a reduced cross-sectional area and may include slits to increase electrical resistance at the fold relative to the adjacent legs. An actuator array includes a plurality of flexible unit-cell actuators formed in a sheet, each unit-cell actuator mechanically coupled to at least one other unit-cell actuator at a coupling region. Plural unit-cell actuators may be mechanically coupled in series, in parallel, or both, may be electrically connected in series, and may move along a defined curve or surface.

Abstract: Methods to systematize the development of machines using inexpensive, fast, and convenient fabrication processes are disclosed. In an embodiment, a folding pattern and corresponding circuit design can provide the blueprints for fabrication. The folding pattern may be provided (e.g. laser machined) on a flat sheet of substrate material, such as a polymer. The circuit pattern may be generated by etching or applying (e.g. sputtering) a copper foil layer onto the substrate. Circuit components and actuators may then be added at specified locations. The flat substrate may then be folded along the predefined locations to form the final machine. The machine may operate autonomously to perform a task.

Abstract: In one embodiment, processing location data collected with a mobile device having a positioning system includes accepting trajectory data representing successive geographic positions of the mobile device, where the positions are associated with corresponding times. A set of coordinate segments is determined to represent in the accepted trajectory data, such that the trajectory data represent repeated traversals of at least some of the coordinate segments. A textual characterization is associated with each segment of the determined set of coordinate segments, and then a representation of the trajectory data (for example, an electronic diary) is formed using the textual characterization of the coordinate segments and stored. In some examples, a text based query associated with the accepted trajectory data is accepted and a response is determined using the stored representation of the trajectory data.

Abstract: An approach to compression of a large (n point or samples) data set has a combination of one or more desirable technical properties: for a desired level of accuracy (?), the number of compressed points (a “coreset”) representing the original data is O(log n); the level of accuracy comprises a guaranteed bound expressed as multiple of error of an associated line simplification of the data set; for a desired level of accuracy and a complexity (e.g., number k of optimal line segments) of the associated line simplification, the computation time is O(n); and for a desired level of accuracy (c) and a complexity of the associated line simplification, the storage required for the computation is O(log n).

Abstract: Self-regulating pressure source. The pressure source includes a chamber enclosing a chemical monopropellant. A moveable boss is attached to a deformable membrane sealing an air chamber, the moveable boss and air chamber being disposed within the chamber. A catalyst is disposed around the membrane so as to be covered by the boss in a retracted position so that the monopropellant is broken down by the catalyst to produce a gas. The gas pressure will increase within the chamber causing air in the air chamber to compress thereby to pull the boss into the retracted position to cover the catalyst thereby to regulate the pressure within the chamber. The self-regulating pressure source is particularly suited to power fluidic elastomeric actuators.

Abstract: Described are a method and an apparatus for color-corrected underwater imaging. A range to an underwater object to be imaged is determined and control values are selected according to the range. Control values are predetermined for a number of ranges according to an optimization of a color quality factor for each range based on the spectra of the optical sources used for illumination and the wavelength-dependent optical transmission of the water for the range. The optical power of each optical source is controlled according to a respective one of the selected control values. Advantageously, an acquired image requires no color correction as the adaptive illumination compensates for the wavelength-dependent losses in the light propagation path from the optical sources to the object and from the object to the imaging device.

Abstract: A flexible unit-cell actuator includes a shape memory alloy sheet having a fold between adjacent legs in one state and a heat source that upon activation concentrates heating of the shape memory alloy sheet at the fold relative to the legs to change the fold between one state and another state. The heat source may include resistive heating due to an electric current passing through the shape memory alloy sheet. The fold typically includes a reduced cross-sectional area and may include slits to increase electrical resistance at the fold relative to the adjacent legs. An actuator array includes a plurality of flexible unit-cell actuators formed in a sheet, each unit-cell actuator mechanically coupled to at least one other unit-cell actuator at a coupling region. Plural unit-cell actuators may be mechanically coupled in series, in parallel, or both, may be electrically connected in series, and may move along a defined curve or surface.

Abstract: Described are a method and an apparatus for color-corrected underwater imaging. A range to an underwater object to be imaged is determined and control values are selected according to the range. Control values are predetermined for a number of ranges according to an optimization of a color quality factor for each range based on the spectra of the optical sources used for illumination and the wavelength-dependent optical transmission of the water for the range. The optical power of each optical source is controlled according to a respective one of the selected control values. Advantageously, an acquired image requires no color correction as the adaptive illumination compensates for the wavelength-dependent losses in the light propagation path from the optical sources to the object and from the object to the imaging device.

Abstract: Methods and structure for dynamically tailoring selection of rich content for recommendation to a user wherein the recommendation process determines recommendations in accordance with past user selections. A server process (102) provides lists of recommended content to a client process (100), through a WAN (104), associated with an identified user. The user on the client process (100) then selects content and provides the server process (102) with a rating through the user feedback input (112).