Abstract: A safety system for autonomously mobile machinery (e.g., automated guided vehicles) achieves safety-rated collision avoidance functionality by detecting objects located in the field of view of a three-dimensional (3D) time-of-flight (TOF) vision system or camera. Incorporating a 3D TOF camera into a collision avoidance system allows a large volume to be monitored for object intrusion, improving reliability of object detection. To ensure reliability of the safety system's obstacle detection capabilities, the collision avoidance system also includes self-diagnostic capabilities that verify the accuracy of the TOF camera's distance measurements even in the absence of a test object within the camera's field of view. This is achieved by tilting the TOF camera downward to include the floor within the camera's field of view, allowing the floor to act as a test object that can be leveraged to verify accuracy of the camera's distance measurements.

Abstract: A time of flight sensor device is capable of generating accurate propagation time information for emitted light pulses using a small number of measurement cycles by using multiple measuring capacitors to capture more return pulse information per pulse period. To mitigate the effects of mismatched measuring capacitors and reading paths, embodiments of the time of flight sensor device perform multiple measuring sequences per measurement operation, permutating the roles of the measuring capacitors for each of the measuring sequences. The data collected by the measuring capacitors for the multiple measuring sequences is then aggregated and used to compute the propagation time and corresponding distance. This technique mitigate yields accurate measurements despite mismatches between reading paths and measuring capacitors without the need to implement pixel-level calibration and compensation, thereby saving calibration time, memory space, and computing time.

Abstract: A time of flight sensor device is capable of extending its total sensing distance using multiple measuring sequences for each distance measuring operation. Such embodiments can execute two or more iterations of a measuring sequence, where the gating signal control sequence for each measuring sequence is offset in time relative to a previous sequence. This yields a greater number of sampling points within which a reflected pulse can be detected and measured, resulting in a total measurable time of flight range that is greater than a measuring operation that uses a fixed timing for the gating signals.

Abstract: A time of flight (TOF) sensor device employs a measuring sequence that facilitates accurate distance measurement across a high dynamic range. In one or more embodiments, for a given measuring sequence in which a distance of an object or surface corresponding to a pixel is to be determined, the TOF sensor device performs multiple iterations of a measuring cycle, whereby for each successive iteration the number of emitted and measured pulses that are accumulated for the iteration is increased relative to the previous iteration of the measuring cycle. In this way, multiple values of increasing resolution are measured for the same physical entity over a corresponding number of measuring cycles. The sensor then selects a value from the multiple measured values that yields the highest resolution without saturating the pixel, and this value is used to determine the pulse propagation time and object distance.

Abstract: An active illumination three-dimensional sensor device is configured with a number of diagnostic functions that can satisfy the requirements of industrial safety within the context of a single-channel safety sensor architecture. The sensor diagnostic functions provide sufficient diagnostic coverage for an optical safety sensor (e.g., a time-of-flight safety sensor) to achieve a desired safety integrity level without the need for multiple channels. The diagnostic features can be applied to one or more components along the single-channel path (e.g., the sequencer, the illumination source, input and/or output optics, image sensor pixel, etc.) to provide a level of diagnostic coverage that renders the optical safety sensor suitable for use within industrial safety applications requiring high safety integrity levels.

Abstract: A safety system for autonomously mobile machinery (e.g., automated guided vehicles) achieves safety-rated collision avoidance functionality by detecting objects located in the field of view of a three-dimensional (3D) time-of-flight (TOF) vision system or camera. Incorporating a 3D TOF camera into a collision avoidance system allows a large volume to be monitored for object intrusion, improving reliability of object detection. To ensure reliability of the safety system's obstacle detection capabilities, the collision avoidance system also includes self-diagnostic capabilities that verify the accuracy of the TOF camera's distance measurements even in the absence of a test object within the camera's field of view. This is achieved by tilting the TOF camera downward to include the floor within the camera's field of view, allowing the floor to act as a test object that can be leveraged to verify accuracy of the camera's distance measurements.

Abstract: A three-dimensional (3D) sensor device achieves accurate distance measurements in the presence of multipath illumination interference (MPII) by estimating the effect of indirect illumination on a given pixel's optical signal measurement and correcting the signal measurement to remove the estimated contribution from indirect illumination. After generating an initial point cloud image of a scene, the sensor device identifies target objects and background objects within the scene, where the background objects are potential sources of indirect illumination. The sensor device estimates the total amount of indirect illumination directed to a point on the target object by the background objects and received at a pixel corresponding to the point, and corrects the measured signal at the pixel to remove the contribution of this estimated indirect illumination.

Abstract: An active illumination three-dimensional sensor device is configured with a number of diagnostic functions that can satisfy the requirements of industrial safety within the context of a single-channel safety sensor architecture. The sensor diagnostic functions provide sufficient diagnostic coverage for an optical safety sensor (e.g., a time-of-flight safety sensor) to achieve a desired safety integrity level without the need for multiple channels. The diagnostic features can be applied to one or more components along the single-channel path (e.g., the sequencer, the illumination source, input and/or output optics, image sensor pixel, etc.) to provide a level of diagnostic coverage that renders the optical safety sensor suitable for use within industrial safety applications requiring high safety integrity levels.

Abstract: A three-dimensional (3D) sensor device achieves accurate distance measurements in the presence of multipath illumination interference (MPII) by estimating the effect of indirect illumination on a given pixel's optical signal measurement and correcting the signal measurement to remove the estimated contribution from indirect illumination. After generating an initial point cloud image of a scene, the sensor device identifies target objects and background objects within the scene, where the background objects are potential sources of indirect illumination. The sensor device estimates the total amount of indirect illumination directed to a point on the target object by the background objects and received at a pixel corresponding to the point, and corrects the measured signal at the pixel to remove the contribution of this estimated indirect illumination.

Abstract: 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.

Abstract: An active illumination three-dimensional sensor device is configured with a number of diagnostic functions that can satisfy the requirements of industrial safety within the context of a single-channel safety sensor architecture. The sensor diagnostic functions provide sufficient diagnostic coverage for an optical safety sensor (e.g., a time-of-flight safety sensor) to achieve a desired safety integrity level without the need for multiple channels. The diagnostic features can be applied to one or more components along the single-channel path (e.g., the sequencer, the illumination source, input and/or output optics, image sensor pixel, etc.) to provide a level of diagnostic coverage that renders the optical safety sensor suitable for use within industrial safety applications requiring high safety integrity levels.

Abstract: A time of flight sensor device is provided that is capable of generating accurate information relating to propagation time of emitted light pulses using a small number of measurements or data captures. By generating pulse time of flight information using a relatively small number of measurement cycles, object distance information can be generated more quickly, resulting in faster sensor response times. Embodiments of the time of flight sensor can also minimize or eliminate the adverse effects of ambient light on time of flight measurement. Moreover, some embodiments execute time of flight measurement techniques that can achieve high measurement precision even when using relatively long light pulses having irregular, non-rectangular shapes.

Abstract: 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.

Abstract: A time of flight sensor device is provided that is capable of generating accurate information relating to propagation time of emitted light pulses using a small number of measurements or data captures. By generating pulse time of flight information using a relatively small number of measurement cycles, object distance information can be generated more quickly, resulting in faster sensor response times. Embodiments of the time of flight sensor can also minimize or eliminate the adverse effects of ambient light on time of flight measurement. Moreover, some embodiments execute time of flight measurement techniques that can achieve high measurement precision even when using relatively long light pulses having irregular, non-rectangular shapes.

Abstract: Systems and techniques for determining sensing margins and/or diagnostic information associated with a sensor are presented. A statistics component generates statistical data based on sensor data associated with a sensing device. A margin component generates sensing margins for the sensing device based on the statistical data. An output component generates an indicator for a changing condition associated with the sensing device based on the sensing margins. In an aspect, a diagnostic component generates diagnostic data for the sensing device based on the statistical data.

Abstract: A time of flight (TOF) sensor device employs a measuring sequence that facilitates accurate distance measurement across a high dynamic range. In one or more embodiments, for a given measuring sequence in which a distance of an object or surface corresponding to a pixel is to be determined, the TOF sensor device performs multiple iterations of a measuring cycle, whereby for each successive iteration the number of emitted and measured pulses that are accumulated for the iteration is increased relative to the previous iteration of the measuring cycle. In this way, multiple values of increasing resolution are measured for the same physical entity over a corresponding number of measuring cycles. The sensor then selects a value from the multiple measured values that yields the highest resolution without saturating the pixel, and this value is used to determine the pulse propagation time and object distance.

Abstract: A time of flight sensor device is capable of extending its total sensing distance using multiple measuring sequences for each distance measuring operation. Such embodiments can execute two or more iterations of a measuring sequence, where the gating signal control sequence for each measuring sequence is offset in time relative to a previous sequence. This yields a greater number of sampling points within which a reflected pulse can be detected and measured, resulting in a total measurable time of flight range that is greater than a measuring operation that uses a fixed timing for the gating signals.

Abstract: A time of flight sensor device is capable of generating accurate propagation time information for emitted light pulses using a small number of measurement cycles by using multiple measuring capacitors to capture more return pulse information per pulse period. To mitigate the effects of mismatched measuring capacitors and reading paths, embodiments of the time of flight sensor device perform multiple measuring sequences per measurement operation, permutating the roles of the measuring capacitors for each of the measuring sequences. The data collected by the measuring capacitors for the multiple measuring sequences is then aggregated and used to compute the propagation time and corresponding distance. This technique mitigate yields accurate measurements despite mismatches between reading paths and measuring capacitors without the need to implement pixel-level calibration and compensation, thereby saving calibration time, memory space, and computing time.

Abstract: An energy-efficient industrial sensor is provided that optimizes power consumption based on characteristics of the requirements of the sensing application in which the sensor is used. Operating parameters of the sensor, such as sensing range, operating frequency, response time, noise immunity, or other such parameters, can be scaled to suit the sensing and response requirements and environmental conditions of the sensing application. This allows the sensor to consume less energy when used in sensing applications that do not require peak sensor performance. In some embodiments, the sensor can measure the environmental or machine operating conditions in its immediate vicinity and dynamically scale its operating parameters based on the measured information. By down-scaling the sensor's operating parameters from their maximum performance levels where appropriate, the overall energy footprint of a network of sensors can be reduced.

Abstract: A time of flight sensor device is provided that is capable of generating accurate information relating to propagation time of emitted light pulses using a small number of measurements or data captures. By generating pulse time of flight information using a relatively small number of measurement cycles, object distance information can be generated more quickly, resulting in faster sensor response times. Embodiments of the time of flight sensor can also minimize or eliminate the adverse effects of ambient light on time of flight measurement. Moreover, some embodiments execute time of flight measurement techniques that can achieve high measurement precision even when using relatively long light pulses having irregular, non-rectangular shapes.