Abstract: A device for optically scanning and measuring an environment is provided. The device includes at least one projector for producing at least one uncoded pattern on an object in the environment. A first camera is provided for recording at least one first image of the object provided with the pattern, the first camera having a first image plane. A second camera is provided for recording at least one second image of the object provided with the uncoded pattern, the second camera being spaced apart from the first camera in order to acquire the uncoded pattern on a second image plane. A controller is provided having a processor configured to determine the three-dimensional coordinates of points on the surface of the object based at least in part on the uncoded pattern, the at least one first image and the at least one second image.

Abstract: The invention relates to a method and arrangement for determining structures and/or geometry of a workpiece in a coordinate measuring machine by means of a tactile-optical measuring method, wherein the position of a shaped probe element is determined in at least one direction by means of a first sensor using an optically lateral measuring method, and the position of the shaped probe element is determined in at least one second direction using at least one distance sensor. In order to allow the error-free detection of the shaped probe element using the sensors, the invention proposes that at least one flexible connector element is used in a mounting for fastening the shaped probe element, permeated by the beam path of the first sensor in the beam direction, wherein the connecting element is transparent and/or is disposed severely out of focus with respect to the first sensor.

Abstract: A non-destructive method of measuring tear lines formed in a surface of a resilient automotive trim panel configured for overlaying an inflatable safety device includes the steps of periodically selecting a trim panel for testing from a flow of in-process trim panels, mounting the selected trim panel to a mounting jig configured to support a region of the selected trim panel adjacent a tear line and to temporarily splay said selected trim panel to expose opposed edges forming at least a portion of the tear line, scanning a 3D image of the opposed edges, storing said 3D image as data in an associated processor, and removing the selected trim panel from the mounting jig. The mounting jig includes a base forming upwardly facing longitudinally elongated converging guide surfaces intersecting at a common apex, and a cover member forming downwardly facing longitudinally elongated converging support surfaces intersecting at a common apex.

Abstract: A method for determining a distance between two spatial points, thus between a first point and a second point, includes recording a first picture from a first viewing point, wherein the first picture includes a reference object and the first point, recording a second picture for a second viewing point, wherein the second picture includes the reference object and the second point and wherein the second viewing point is different than the first viewing point and finally determining the distance between the first point and the second point from picture data of the first picture and picture data of the second picture using a known dimension of the reference object. Thereby, the first point and/or the second point can be arranged outside a plane encompassing the reference object.

Abstract: Various embodiments provide an improved conveyor belt comprising: a visible surface having a primary axis oriented in a machine direction; a plurality of first stripes having a first visible appearance, each of the plurality of first stripes at least in part defining the visible surface and being oriented perpendicular to the primary axis; and a plurality of second stripes having a second visible appearance, each of the plurality of second stripes at least in part defining the visible surface and being oriented perpendicular to the primary axis, wherein: the second visible appearance provides a contrasting appearance relative to the first visible appearance; and each of the plurality of second stripes are located intermediate two of the plurality of first stripes such that the plurality of first and second stripes collectively define an alternating contrasting pattern on the visible surface of the improved conveyor belt.

Abstract: Methods and systems of sensing conditions in a fiber includes launching a light beam into a fiber. A first branch of scattered light is set to a mode other than a fundamental mode. A second branch of scattered light is optically filtered to remove unscattered input light. Brillouin scattered light is coherently detected on the first branch to produce a combined temperature/strain profile of the fiber. Raman scattered light on the second branch is directly detected to produce a temperature profile of the fiber. A strain profile of the fiber is determined, using a processor, based on the combined temperature/strain profile and the temperature profile.

Abstract: A surface data acquisition, storage, and assessment system for detecting and quantifying similarities or differences between stored data and data collected from a scan. The system operates utilizing a method that decreases the time required for calculating a pose estimate thus increasing its performance making it more practical for applications that require real-time operations. In a preferred embodiment the system comprises one or more sensing components for scanning and measuring surface features of an object for determining the identity of the object, and determines differences between data obtained from two or more scans.

Abstract: To measure the three-dimensional shape of a target object with higher accuracy, a three-dimensional shape measurement apparatus projects a pattern image to a predetermined measurement area including a support structure on which the target object is placed; and captures an image of the predetermined measurement area. In addition, the apparatus derives, based on the captured image, a first correction value for correcting a position fluctuation of a support structure, and a second correction value for correcting a fluctuation of a projection position; and calculates, based on the captured image and the first correction value and the second correction value, a plurality of coordinates on a surface of the target object.

Abstract: An object detection device includes at least one light source, an irradiation optical system configured to irradiate a measured object with light emitted from the light source, a light reception element configured to image reflected light reflected by the measured object, and a detection unit configured to detect the measured object based on the reflected light received by the light reception element, and the irradiation optical system includes conversion means for converting the light emitted from the light source into a plurality of regular patterns.

Abstract: An alignment device to facilitate the alignment of a pulley and a sheave. The device may be used to align invention can be used in adjustable sheaves and in sheaves with multiple grooves. The device includes a laser beam generation component with a pulley contact section configured for releasable engagement with an interior surface of the groove of the pulley. The device also includes a laser beam target component with a sheave contact section configured for releasable engagement with an interior surface of the groove of the sheave. When the laser beam generation component and the laser beam target component are positioned facing one another in the pulley and sheave, respectively, the laser beam from the laser beam generation component contacts the target of the laser beam target component and wherein when the laser beam aligns with the target, the pulley and the sheave are aligned.

Abstract: A light-emitting device to detect passage or smoke in the emitted beam. The device includes a source of invisible radiation, a source of visible laser radiation, an alignment component to align the central axis of the visible radiation with an axis parallel to the central axis of the invisible radiation, and a switch to turn off the visible laser source. The device can further include a housing containing both sources of radiation. The switch is configured to be controlled by the closing of the housing and the source of visible laser radiation is turned off in response to the closure of the housing.

Abstract: A wall area estimation system generates an estimated wall area measurement of a building based on the received roof measurements (e.g., those generated by, received from or found in a three-dimensional model of the roof) and a reference distance. The reference distance is a measurement indicative of a distance between the roof and a model ground surface placed on an image of the building where the walls of the building meet the ground. This reference distance may be used to determine how for down to extend the walls of the building (e.g., to a ground level) when building a three-dimensional digital model of the building to aid in generating wall area measurements. The resulting wall measurements, roof measurements, measurements of areas missing from the wall used to generate a wall estimate report, or a combined roof and wall estimate report including various different identifiers indicating the different features and measurements based on the three-dimensional model.

Abstract: The invention relates to a method for testing the proper functionality of an elevator, in which a car (3) is movable in an elevator shaft having an elevator shaft excavation space, and a characteristic value is ascertained under predefined test conditions to determine the proper functionality of the elevator. To simplify the method, it is proposed according to the invention that a change of the distance (A) between a car lower side and a fixed measuring point in the elevator shaft excavation space be measured to ascertain the characteristic value.

Abstract: Methods and systems for using spectrally separated light pulses to collect more LIDAR information are presented. In one example, a laser pulse may be directed to a point on an object and a corresponding return light signal may be received. The return light signal may be wavelength separated into a plurality of spectral pulse components. Each of the spectral pulse components may be propagated down a separate fiber optic delay line each having a different length to provide a plurality of time-separated spectral pulse components. The time-separated spectral pulse components may be combined to provide a recombined spectral pulse signal. The recombined spectral pulse signal can be provided to an intensity-related measuring/detection circuitry to generate corresponding object location information and object spectral information regarding the point on the object.

Abstract: In an angular velocity sensor, when a width of a detection frequency band is set to f1 [Hz], a resonance frequency in a first rotational vibration mode in which a base portion rotates and vibrates around a detection axis with respect to fixing units in association with the deformation of beam portions is set to f2 [Hz], a detuning frequency is set to f3 [Hz], and a resonance frequency in a second rotational vibration mode, having a phase opposite to that of the first rotational vibration mode, in which the base portion rotates and vibrates around the detection axis with respect to the fixing units in association with the deformation of the beam portions is set to f4, a relation of f1<f2<f3<f4 or a relation of f1<f2<f4<f3 is satisfied.

Abstract: A gyroscope includes a cylindrical shell having a first end and a second end, a base on the second end of the shell, a substrate, an anchor coupling the base to the substrate, and electrodes for driving and sensing mechanically separated from the cylindrical shell.

Abstract: Methods and apparatus for sensing linear acceleration with a MEMS resonator mass, alone, or concurrently with sensing rate of rotation. A resonator mass, which may be a disk or a ring structure, is driven at a resonance frequency of one of the vibration modes of the resonator mass. The amplitude of vibration of that mode is sensed by a set of at least two drive-sense electrodes disposed at opposing positions across the resonator mass. A linear acceleration is derived based at least on a difference between signals of the opposing electrodes. Linear acceleration may be sensed in multiple orthogonal dimensions using multiple pairs of opposing electrodes. Rotation rate may be derived concurrently by sensing the energy coupled into an orthogonal mode of the resonator mass.

Abstract: This document discusses among other things apparatus and methods for a proof mass including split z-axis portions. An example proof mass can include a center portion configured to anchor the proof-mass to an adjacent layer, a first z-axis portion configure to rotate about a first axis using a first hinge, the first axis parallel to an x-y plane orthogonal to a z-axis, a second z-axis portion configure to rotate about a second axis using a second hinge, the second axis parallel to the x-y plane, wherein the first z-axis portion is configured to rotate independent of the second z-axis portion.

Abstract: There is provided a solution comprising detecting that a positioning device is within a predetermined control area associated with a building, acquiring a first sequence of magnetic field measurements carried out by the positioning device, wherein the first sequence represents at least one of the magnitude and the direction of Earth's magnetic field; determining that an operational environment of the positioning de-vice has changed between an indoor environment and an outdoor environment when a at least one predetermined criterion with respect to the first sequence is met; and causing actuation of a predetermined software function in or with respect to the positioning device when the operational environment of the positioning device has changed.

Abstract: A method to improve estimation and stabilization of heading in an inertial navigation system is provided. The method includes operating an inertial measurement unit oriented in a first orientation, forward-rotating the operational inertial measurement unit by a selected-rotation angle about a Z-body axis of the inertial navigation system, wherein the inertial measurement unit is oriented in a second orientation, operating the inertial measurement unit oriented in the second orientation, reverse-rotating the operational inertial measurement unit by the selected-rotation angle about the Z-body axis, wherein the inertial measurement unit is oriented in the first orientation, continuously receiving information indicative of an orientation of the inertial measurement unit at a rotational compensator, and continuously-rotationally compensating navigation module output at the rotational compensator, wherein output of the rotational compensator is independent of the rotating.

Abstract: A traveling direction velocity calculation device 1 calculates a posture of an acceleration sensor 10 with respect to a user, using a detection result represented in a local coordinate system associated with the acceleration sensor 10, detecting acceleration, which is worn on a user's body, when a change in the detection result of the acceleration sensor 10 satisfies a predetermined specific condition. The detection result of the acceleration sensor 10 at a time different from that when the posture is calculated and at a time when the specific condition is satisfied is transformed, using the calculated posture, to a mobile body coordinate system associated with a user. A velocity in a traveling direction of the user is calculated using the transformed detection result.

Abstract: A system and method for generating a seamless road network of a large geographical area includes a plurality of GPS probe traces extending across a geographical area. The probe traces are divided into sub-sets base on criteria, such as accuracy. A plurality of threads simultaneously employ the sub-sets traces to generate an independent network of the entire geographical area. The networks generated using sub-sets having a high accuracy are preferred over networks generating using sub-sets having a lower accuracy. The independent networks are combined to form a seamless networks of road segments.

Abstract: Aspects of the present disclosure relate to a vehicle for maneuvering a passenger to a destination autonomously. The vehicle includes one or more computing devices that receive a request for a vehicle from a client computing device. The request identifies a first location. The one or more computing devices also determine whether the first location is within a threshold outside of a service area of the vehicle. When the location is within the threshold distance outside of the service area of the vehicle, the one or more computing devices identify a second location within the service area of the vehicle where the vehicle is able to stop for a passenger and based on the first location. The one or more computing devices then provide a map and a marker identifying the position of the second location on the map for display on the client computing device.

Abstract: A method for inputting position data into a navigation device of a vehicle, includes the steps: —displaying (10) positions on a graphical output unit of a mobile radio terminal device; —marking (12) one of the displayed positions on the output unit by a mark; —displaying (14) a graphical representation of a symbol for a vehicle by the output unit, to which vehicle the mobile radio terminal device makes vehicle-specific communication link data available; —shifting (16) the mark to the symbol of the vehicle or the symbol of the vehicle to the mark on the output unit; and —transmitting (18) position data identifying the marked position to the navigation device of the vehicle.

Abstract: An map display method wherein a point of interest is displayed on a map, the geo-coordinates updated by a trusted person and then stored for subsequent display to the displays of a plurality of different computers such as through the internet.

Abstract: A vehicle localization system and method uses a hybrid communication layer. The system and method detect a vehicle location and transmit the vehicle location to an application layer using a plurality of communication methods. In addition, the method and system can determine a preferable communication method. The preferable communication method can be dependent on past vehicle locations.

Abstract: Computationally implemented methods and systems that are designed for receiving a request for transporting one or more end users; identifying one or more transportation vehicle units for transporting the one or more end users to one or more destination locations based, at least in part, on determining whether the one or more transportation vehicle units have one or more delivery package obligations; and transmitting one or more directives that direct the one or more transportation vehicle units to rendezvous with the one or more end users in order to transport the one or more end users to the one or more destination locations. In addition to the foregoing, other aspects are described in the claims, drawings, and text.

Abstract: A method is provided for unmanned control of at least one vehicle by a central processing unit. The central processing unit controls the at least one vehicle on a route determined by the central processing unit from a first location on the route to at least one second location on the route. The second location on the route is a parking site. The central processing unit further controls the vehicle so that the vehicle, after a parking operation at the second location, is provided automatically to a user for acceptance at a retrieval location as further location on the route. The route is calculated by the central processing unit dynamically depending on information concerning further routes for further vehicles managed by the central processing unit.

Abstract: A method for region guided and change tolerant fast shortest path determination and graph preprocessing for network management and control. In an embodiment, a method includes partitioning, by a network component, a plurality of network nodes into a plurality of regions, each network node belonging to one of the regions; identifying, by the network component, border nodes for each region, each border node in a region connecting to at least one border node in a connecting region; determining, by the network component, intervals between regions according to the border nodes, each interval comprising a minimum distance and a maximum distance between two regions; determining, by the network component, a path from a source node to a target node according to the intervals.

Abstract: A method, system, and computer program product for social media based weighted route selection are provided in the illustrative embodiments. It is detected that a first route and a second route are possible between two places. A first set of points of interest (POIs) is identified relative to the first route. By accessing a social media source, a set of social information is collected comprising information related to a POI. A subset of the social information is organized into a set of categories related to the POI. Each information in the subset is assigned a corresponding weight to compute a value for each information. A total value of each POI is determined using the computed values. From the first route and the second route, that route as presented as socially preferred route which has a higher total route value.

Abstract: Some embodiments of the invention provide a navigation application that allows a user to peek ahead or behind during a turn-by-turn navigation presentation that the application provides while tracking a device (e.g., a mobile device, a vehicle, etc.) traversal of a physical route. As the device traverses along the physical route, the navigation application generates a navigation presentation that shows a representation of the device on a map traversing along a virtual route that represents the physical route on the map. While providing the navigation presentation, the navigation application can receive user input to look ahead or behind along the virtual route. Based on the user input, the navigation application moves the navigation presentation to show locations on the virtual route that are ahead or behind the displayed current location of the device on the virtual route. This movement can cause the device representation to no longer be visible in the navigation presentation.

Abstract: Provided is a computer system and method for mapping a visual path. The method includes receiving one or more images included in a predefined area; receiving one or more parameters associated with the image; and integrating the images and parameters into a map of the predefined area to enable mapping the visual path through the predefined area in response to one or more input path parameters.

Abstract: Techniques are provided for presenting a route using a route presentation that provides both a context map and one or more detail route maps. Narrative instructions for the route also may be presented. The presentation of the context map and the one or more detail route maps may be interactive. The route presentation also may be user controllable such that a user may control the portions of a route that are printed. The route presentation also may include a re-routing feature that allows a user to request that a new route be identified that avoids a particular maneuver or maneuvers in a route.

Abstract: A method and apparatus for predicting traffic on a transportation network where real time data points are missing. In one embodiment, the missing data is estimated using a calibration model comprised of historical data that can be periodically updated, from select links constituting a relationship vector. The missing data can be estimated off-line whereafter it can be used to predict traffic for at least a part of the network, the traffic prediction being calculated by using a deviation from a historical traffic on the network. The invention further discloses a method for in-vehicle navigation; and a method for traffic prediction for a single lane.

Abstract: A fiber-optic sensor array (100) comprises a line array of fiber-optic sensor packages (AX, BX, CX, DX, AY, BY, CY, DY, AZ, BZ, CZ, DZ) each having a package input/output (i/o) fiber and each being arranged to output a finite output pulse series of optical output pulses via the package i/o fiber in response to input thereto of one or more interrogating optical pulses. The array further comprises a fiber-optic bus (104,106, 108, 110) extending along the length of the line array, each package i/o fiber being optically coupled to the fiber-optic bus at a respective positions along the line array. The array allows interrogation at a higher frequency than is the case for a serial array of the same number of fiber-optic sensing packages.

Abstract: A radiation detector head assembly is provided that includes a detector housing and a rotor assembly. The detector housing defines a cavity therein. The rotor assembly includes a detector unit, a body, and a sealing member. The body defines an opening oriented in the imaging direction. The body is disposed at a distance from the detector housing within the cavity defining a passageway extending axially along the body. The sealing member includes a body extending across the opening. The sealing member is coupled to at least one of the shielding unit or the collimator, and is mounted within the cavity to provide a gas-tight seal along the imaging direction between the passageway and the detector unit.

Abstract: Described are techniques for performing qualification protocol testing. A qualification entity category is selected indicating a category of an entity for which a qualification test protocol is generated. One or more qualification tests are selected and included in the qualification test protocol. Test information is specified for the one or more qualification tests. The test information includes first information identifying one or more code modules executed to perform said one or more qualification tests, second information identifying test inputs to said one or more code modules, and third information specifying how to evaluate tests results from executing each of said one or more qualification tests. A qualification protocol structure including said test information is generated.

Abstract: A method for controlling a sensor by a mobile device, the method comprising: executing an application performing a task; obtaining first sensor data using a first sensor to perform the task; receiving second sensor data obtained using a second sensor of at least one communicably connected external device; comparing the first sensor data with the second sensor data; and when the first sensor data is replaceable with the second sensor data, controlling an operation of the first sensor and the second sensor according to a battery state of the mobile device and the external device.

Abstract: A vortex flowmeter has first and second process connections with a meter inlet and outlet, respectively, therein. The first and second process connections are configured to connect, respectively, to upstream and downstream segments of a fluid pipeline. A fluid conveyance system conveys fluid from the inlet to the outlet and divides the fluid into separate fluid streams that flow through separate passages. Each of the passages has its own vortex metering unit configured to generate and detect vortices in the respective fluid stream. A processing system is configured to calculate a sum of the flow rates through all of the fluid streams.

Abstract: Method for operating for measuring the flow velocity of a flowing medium using a measuring device in which a magnetic field is induced in the flowing medium and on which a interference voltage is superimposed. During compensation measuring, a first magnetic flux density is generated in the medium and a first measuring voltage determined, a second magnetic flux density is generated in the medium and a second measured voltage determined, and a third magnetic flux density is generated in the medium and a third measured voltage determined. The flow velocity is determined from the first and second magnetic flux densities and measured voltages, and the interference voltage is determined form the third magnetic flux density and measured voltage and the determined flow velocity. Then, a fourth measured voltage is determined, and the flow velocity re-determined from the third magnetic flux density, the fourth measured voltage and the determined interference voltage.

Abstract: The invention relates to a thermal flow sensor comprising: a support, at least one element intended to be vibrated relative to the support, suspension means for said vibrating element relative to the vibrating element, means for heating the vibrating element, means for electrostatic excitation of the vibrating element so as to vibrate it at its resonance frequency, piezoelectric gauges for detecting the resonance frequency variation of the vibrating element, the gauges forming means for heating the vibrating element by Joule effect and the suspension means comprising two beams formed by nanowires so as to reduce the heat losses from the vibrating element toward the support.

Abstract: A flow rate measuring device with high precision is provided. The flow rate measuring device includes a sub-passage that takes a part of the fluid flowing in a main passage, first temperature measuring means for measuring a temperature of the fluid flowing in the passage, second temperature measuring means for measuring a temperature of a fluid flowing in the sub-passage, detecting means for detecting a flow rate of the fluid flowing in the sub-passage, and measuring means for measuring a flow rate of the fluid flowing within the main channel on the basis of an output of the first temperature measuring means, an output of the second temperature measuring means, and an output of the detecting means.

Abstract: The present invention is a system and method of visualizing fluid flow around an object, such as an aircraft or wind turbine, by aligning the object between an imaging system and a celestial object having a speckled background, taking images, and comparing those images to obtain fluid flow visualization.

Abstract: Method for determining the density (D) of a multiphase fluid (F) flowing through a pipe (1) and containing a gas (G) which determines a fluctuation of the actual instantaneous density of the fluid (F), said method comprising the following steps: defining a series of consecutive time periods (S0, S) which are shorter than the time length corresponding to the highest frequency-component of the fluctuation of the actual instantaneous density; conveying through a section (2) of the pipe (1) a photon beam (3) suited to undergo an attenuation while crossing the fluid (F); counting the actual number (A) of photons of the beam (3) which cross the pipe (1) during a first time period (S) of the series; calculating a corrected count (C) as the weighted average value of the actual count (A) and of the corrected count (C0) calculated for the preceding time period (S0); converting the value of the corrected count (C) into a corresponding value of the density (D) of the multiphase fluid (F) for the first time period (S) thr

Abstract: Technical solutions are described for predicting linepack delays. An example method includes receiving temporal sensor measurements of a first fluid-delivery pipeline network and generating a causality graph of the first fluid-delivery pipeline network. The method also includes determining a topological network of the stations based on the causality graph, where the topological network identifies a temporal delay between a pair of stations. The method also includes generating a temporal delay prediction model based on the topological network and predicting the linepack delays of a second fluid-delivery pipeline network based on the temporal delay prediction model, where a compressor station of the second fluid-delivery pipeline network compresses fluid based on the predicted linepack delays to maintain a predetermined pressure.

Abstract: In an embodiment, a method of sensing an ink level includes applying a pre-charge voltage Vp to a sense capacitor to charge the sense capacitor with a charge Q1, sharing Q1 between the sense capacitor and a reference capacitor, causing a reference voltage Vg at the gate of an evaluation transistor, and determining a resistance from drain to source of the evaluation transistor that results from Vg.

Abstract: A hematology instrument with liquid level detection for liquid in a container is provided. The hematology instrument includes a probe disposed next to a container site. The probe is displaceable relative to the container site to enter a container when positioned at the container site. Further, the probe is electrically grounded. The hematology instrument includes a capacitive sensor having at least one capacitive electrode disposed next to the container site. The capacitive sensor also has a detection module to detect capacitive changes at the at least one capacitive electrode when the probe contacts liquid in the container. The hematology instrument also includes a calibration module configured to calibrate the capacitive sensor a plurality of times as the probe displaces relative to the container site to enter the container. Kits and methods related thereto are also provided.

Abstract: Magnetic field sensor feedback for diagnostics is disclosed herein. A disclosed example apparatus includes a first magnetic field sensor to provide a first output signal in response to a magnetic field generated by a magnet coupled to a movable portion of a process control device, and a second magnetic field sensor to provide a second output signal in response to the magnetic field. The disclosed example apparatus also includes a processor to use the first and second output signals to generate diagnostic information associated with a feedback of the process control device.

Abstract: A checkweighing device, checkweighing systems employing one or more checkweighing devices, and methods of operation thereof. The checkweighing devices are designed for installation between parallel, spaced apart and vertically offset infeed and outfeed conveyors. Each checkweighing device includes a weighing cell with a weighing platform; a slide chute and at least one sorting gate for directing items either to the outfeed conveyor or to a discard receiver; and a power-actuated rake for sweeping incoming items from the infeed conveyor to the weighing platform, and sweeping weighed items from the weighing platform to the slide chute. While in no way limited to such a use, exemplary checkweighing device, system and method embodiments are well-suited for automatically checking the individual weights of small articles of high value, and/or other items that need to be weighed with high accuracy.

Abstract: An apparatus to detect vibration is provided. The apparatus comprises an optical transmitter and an optical receiver. The optical transmitter is configured to send an optical signal that is modified by a vibration sensor. The optical receiver configured to receive the optical signal from the vibration sensor, the optical signal comprising fluctuations responsive to vibration of the vibration sensor. The optical signal includes a radio frequency (RF) signal. The vibration sensor is comprised by an optical assembly configured to detect underground vibrations.