A three-dimensional (3D) sensor device achieves high intrusion detection probability while keeping the probability of a false intrusion detection low by capturing a set of multiple spatial or temporal samples of a measured parameter for an object detected in the sensor's field of view. When an object is detected in the field of view, the TOF sensor device defines a window of N pixels comprising a subset of the pixels corresponding to the object, and obtains N distance measurements corresponding to the N pixels of the window. If the number of the N distance values that are less than a defined threshold distance is equal to or greater than a selected threshold value M (an integer less than N), the TOF sensor device determines that the object is intruding within a protective field and generates a suitable output.

Techniques are disclosed for detecting human presence and tracking motion within a given area using light reflections. Activity is detected by receiving light encoded with source-identifying data reflected from the area and sensing changes, caused by human presence in the area, from a previously established baseline in the light reflection profile for the area. The baseline is updated over time based on human movement and/or as the area changes. Location-indicative changes in the current baseline that are greater than a certain threshold indicate a change in occupancy state of that location. In some embodiments, lightguides are used to define a specific field-of-view for the sensors. The combination of a known field-of-view and a known source of reflected light allows location of each occupant's activity to be tracked within the area. Occupancy can be detected or inferred based on activity tracked entering the area followed by lack of an exit event.

A process executes at an electronic system. The process identifies device characteristics of an imaging device that includes signal emitters and signal detectors. The process illuminates a field of view by signals from the signal emitters according to a modulation signal generated by the imaging device. At each of the signal detectors, the process obtains a response signal, and samples the response signals to form a response vector. The process obtains a lookup table corresponding to the modulation signal and the device characteristics. The field of view is partitioned into a 3-dimensional plurality of voxels, and the lookup table specifies, for each voxel, expected signals received by the signal detectors when the voxel is filled and the signal emitters illuminate the field of view according to the modulation signal. The process compares the response vector to the lookup table to determine which voxels are filled.

A process executes at an electronic system. The process identifies device characteristics of an imaging device that includes signal emitters and signal detectors. The process illuminates a field of view by signals from the signal emitters according to a modulation signal generated by the imaging device. At each of the signal detectors, the process obtains a response signal, and samples the response signals to form a response vector. The process obtains a lookup table corresponding to the modulation signal and the device characteristics. The field of view is partitioned into a 3-dimensional plurality of voxels, and the lookup table specifies, for each voxel, expected signals received by the signal detectors when the voxel is filled and the signal emitters illuminate the field of view according to the modulation signal. The process compares the response vector to the lookup table to determine which voxels are filled.

A laser scanning sensor includes a distance data acquisition unit which acquires distance information in each measurement direction, and a memory which stores, as background distance information, a distance of an outer periphery of the detection area in each measurement direction. The sensor also includes a mirror surface determination unit which determines the presence of a reflecting surface when the distance information in continuous measurement directions is greater by at least a predetermined distance than the corresponding background distance information, and when this state changes thereafter by at least a predetermined rate in a predetermined time, a human body determination unit which extracts a portion of the distance information that may correspond to a human body and determines whether it corresponds to a human body, and an alarm output control unit which outputs an alarm signal when the presence of the reflecting surface or the human body is confirmed.

A laser scanning sensor includes a distance data acquisition unit which acquires distance information in each measurement direction, and a memory which stores, as background distance information, a distance of an outer periphery of the detection area in each measurement direction. The sensor also includes a mirror surface determination unit which determines the presence of a reflecting surface when the distance information in continuous measurement directions is greater by at least a predetermined distance than the corresponding background distance information, and when this state changes thereafter by at least a predetermined rate in a predetermined time, a human body determination unit which extracts a portion of the distance information that may correspond to a human body and determines whether it corresponds to a human body, and an alarm output control unit which outputs an alarm signal when the presence of the reflecting surface or the human body is confirmed.

An intrusion detection system and method are provided. The intrusion detection system may be configured to detect an intruder or authorized person in an area based on light-based feedback and absence of wireless communications with a remote device.

A process executes at an electronic system. The process identifies device characteristics of an imaging device that includes signal emitters and signal detectors. The process illuminates a field of view by signals from the signal emitters according to a modulation signal generated by the imaging device. At each of the signal detectors, the process obtains a response signal, and samples the response signals to form a response vector. The process obtains a lookup table corresponding to the modulation signal and the device characteristics. The field of view is partitioned into a 3-dimensional plurality of voxels, and the lookup table specifies, for each voxel, expected signals received by the signal detectors when the voxel is filled and the signal emitters illuminate the field of view according to the modulation signal. The process compares the response vector to the lookup table to determine which voxels are filled.

A process executes at an electronic system. The process identifies device characteristics of an imaging device that includes signal emitters and signal detectors. The process illuminates a field of view by signals from the signal emitters according to a modulation signal generated by the imaging device. At each of the signal detectors, the process obtains a response signal, and samples the response signals to form a response vector. The process obtains a lookup table corresponding to the modulation signal and the device characteristics. The field of view is partitioned into a 3-dimensional plurality of voxels, and the lookup table specifies, for each voxel, expected signals received by the signal detectors when the voxel is filled and the signal emitters illuminate the field of view according to the modulation signal. The process compares the response vector to the lookup table to determine which voxels are filled.

Sensors, systems, and methods for data center security are provided. In one example, a data center monitoring system includes at least one sensor configured to be attached to a fixture in a data center. The sensor is configured to transmit an optical signal towards a reflective component for detecting an unauthorized access attempt to the fixture. The system also includes at least one monitoring device configured to communicate with the at least one sensor. The monitoring device is configured to receive a signal from the at least one sensor indicative of the unauthorized access attempt to the fixture.