CONTACTLESS MOTION DETECTION SENSOR THAT USES DISTANCE AND INTENSITY STATISTICS

Abstract

Devices and associated methods refer to jam detection when the intensity of a reflected signal exceeds a predetermined intensity threshold and an intensity window metric based on historical intensity value(s) has not exceeded an intensity window threshold for longer than a predetermined time threshold. In an illustrative example, a jam detection unit (JDU) might emit a signal and detect a reflection of that signal. The JDU might, for example, compare the intensity of the reflected signal to the intensity threshold. The JDU might, for example, compare the intensity threshold to at least one historical intensity value to determine the intensity window metric. If the intensity value exceeds the intensity threshold and the intensity window metric has not exceeded the intensity window threshold for longer than the time threshold, then the JDU might, for example, generate a jam signal.Several methods can usefully detect jams based on the intensity of a reflected signal.

Description

CONTACTLESS MOTION DETECTION SENSOR THAT USES DISTANCE AND INTENSITY STATISTICS CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of U.S. application serial number 17 / 654,010, entitled Non-Contact Motion Detection Sensor Utilizing Distance and Intensity Statistics, filed by Oberpriller, et al., on March 8, 2022, and claims the benefit of that application. This application and U.S. application serial number 17 / 654,010 both claim the benefit of U.S. provisional application serial number 63 / 158,697, entitled Non-Contact Motion Detection Sensor Utilizing Distance and Intensity Statistics, filed by Oberpriller, et al., on March 9, 2021. This application incorporates the entire content of the application(s) mentioned above by reference. The subject matter of this application may have common inventive authorship with and / or may relate to the subject matter of the following documents: • US application serial number 17 / 072,028, entitled Image-Based Jam Detection [Image-Based Jam Detection, filed by Wade Oberpriller, et al., on October 15, 2020; • US application serial number 62 / 916,087, entitled Imaging System Using Triangulation, filed by Wade Oberpriller, et al., on October 16, 2019; • U.S. application serial number 62 / 924,020, entitled Imaging System Using Triangulation, filed by Wade Oberpriller, et al., on October 21, 2019; and, • U.S. application serial number 17 / 303,061, entitled Pixel Domain Field of Triangulation Sensors, filed by Wade Oberpriller, et al., on May 19, 2021. This application incorporates the entire content of the aforementioned application(s) by reference. TECHNICAL FIELD Several modalities generally refer to contactless motion detection. 7. i hRnn / pznz / Β / γΐΛΐ BACKGROUND OF THE INVENTION Conveyor belts typically transport objects from one location to a desired second location. There are many different types of conveyor belts. For example, conveyor belts can consist of surfaces that include rollers, wheels, woven or textured belts, or some other surface that easily allows the movement of materials or objects from one place to another. Some conveyor belt monitoring systems can monitor the movement of objects on a conveyor belt. Specifically, these systems can determine whether objects being transported are flowing (e.g., moving freely) or if the flow is jammed (e.g., stopped and no longer moving as expected). In some cases, determining the flow of objects on the conveyor belt may involve direct human intervention by a user. For example, the user may directly observe the objects as they move along the belt from one point to another. In other cases, monitoring the flow of objects may be performed by a camera-based system that records the movement of the objects as they are transported along the conveyor belt. The objects being transported can be of various types. As can be observed from the perspective of a conveyor belt monitoring system located at an observation point, objects on the conveyor belt can, in various applications, exhibit different shape factors and / or external profiles. For example, some objects may appear as a nearly continuous stream scattered along the conveyor belt, with intermittent spacing that may result in a non-deterministic distribution of spacing between objects. In some applications, objects may be distributed along the conveyor belt in a substantially regular or uniform (e.g., deterministic) manner.In some conveyor systems, the shape profiles and / or orientations of monitored objects may be uniform or non-uniform, such as individual boxes of various sizes and shapes, or continuous and uniform, such as a long roll of paper or paper towels. U.S. patent application serial number 2015 / 329296A1, filed by Alexander Shteinfeld et al., discloses a conveyor jam detection system. European patent application number EP3188461A1, filed by Deliang Zhang, discloses a method, apparatus, and device for calibrating detection distances. U.S. patent number 5,970,433, filed by Koji Oka et al., discloses an obstacle detection sensor. U.S. patent number 5,914,785, filed by Stephen W. Allison et al., discloses a method and apparatus for making absolute distance or range measurements using Fresnel diffraction.The publication of the US patent application serial number 2012 / 023929A1 filed by Masanobu. 7. i hRnn / cznz / B / YiAi Hongo et al., discloses a paper feeding system that has a jam detection unit. BRIEF DESCRIPTION OF THE INVENTION Devices and associated methods refer to jam detection when the intensity of a reflected signal exceeds a predetermined intensity threshold and an intensity window metric based on historical intensity value(s) has not exceeded an intensity window threshold for longer than a predetermined time threshold. In an illustrative example, a jam detection unit (JDU) might emit a signal and detect a reflection of that signal. The JDU might, for example, compare the intensity of the reflected signal to the intensity threshold. The JDU might, for example, compare the intensity threshold to at least one historical intensity value to determine the intensity window metric. If the intensity value exceeds the intensity threshold and the intensity window metric has not exceeded the intensity window threshold for longer than the time threshold, then the JDU might, for example, generate a jam signal.Several methods can usefully detect jams based on the intensity of a reflected signal. Several approaches can achieve one or more advantages. For example, in one instance, a cost-effective and competitive advantage results from using a minimal amount of hardware for jam detection. For instance, a single electromagnetic signal source (e.g., optical), such as a laser triangulation sensor, can efficiently project a linear optical beam that illuminates a target object being transported by a conveyor system and generates a detection signal based on the reflection of the linear optical beam from the target object and its impact on a corresponding detection surface. The detection signal can indicate whether the object is jammed or moving.Such modalities can, by way of example and not limitation, achieve effective detection results with minimal hardware (for example, with an optical image source that may include a laser and a linear image reader for intensity and / or distance measurement, and a processing engine). In some modalities, steps within a method can effectively provide image processing to determine motion based on comparing intensity and / or distance with one or more predetermined thresholds. In some configurations, a sensor can, for example, effectively discriminate between acceptable movement and a jammed state when minimal distance variations occur. For instance, configurations incorporating intensity measurements can accurately determine the existence of a non-jamming state for large passing objects with minimal distance variation from the sensor, based on variations in measured intensity over time (e.g., due to labeling or color patterns). 7. i hRnn / cznz / B / YiAi In some embodiments, a sensor can usefully detect, by way of example and not limitation, whether a jam exists on a substantially flat surface based, at least in part, on intensity measurements. Such embodiments can, for example, usefully enable the accurate, non-contact detection of a jam on flat sheets (e.g., paper, tissue, fabric). In some configurations, a sensor operating in background mode can usefully determine a non-jamming state when a predetermined stationary background is detected. The predetermined stationary background, for example, can be detected according to a predetermined intensity threshold. In some modes, a sensor operating in a backgroundless mode can usefully determine a non-jamming state when no object is detected in a predetermined detection zone. The predetermined detection zone can be defined according to a predetermined intensity threshold. In several modes, the intensity threshold can be predetermined during a training operation. Details of various embodiments are presented in the accompanying drawings and in the description below. Other features and advantages will become apparent from the description and figures, and from the claims. BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates a perspective view of an example implementation of a motion detection system that implements jam detection units operating in both background and backgroundless modes in an illustrative use case. Figure 2 illustrates a top view of an example implementation of a motion detection system that implements a background mode in an illustrative use case. Figure 3 illustrates a top view of an example implementation of a motion detection system that implements a backgroundless mode in an illustrative use case. Figure 4 illustrates a top-level block diagram of an example jam detection circuit. Figure 5A illustrates a flowchart that presents in detail an example motion detection process that implements a background mode. Figure 5B illustrates a flowchart that presents in detail an example background mode training process. Figure 6A illustrates a flowchart that presents in detail an example motion detection process that implements a backgroundless mode. Figure 6B illustrates a flowchart that presents in detail an example backgroundless mode training process. 7. i hRnn / cznz / B / YiAi Similar reference symbols in the various figures indicate similar elements. DETAILED DESCRIPTION OF THE INVENTION To facilitate understanding, this document is organized as follows. First, an example use case of scanners deployed in background and backgroundless modes to detect conveyor movement is briefly introduced with reference to Figure 1. With reference to Figure 2, an example jam detection motor system suitable for operation in either mode is introduced. Then, with reference to Figures 2-3, example implementations of jam detection motors operating in background and backgroundless modes are introduced. The discussion then continues with an example jam detection unit modality with reference to Figure 4. Moving on to Figures 5A-6B, example motion detection processes are discussed. Finally, features and details of additional examples are discussed. In some modalities, an electromagnetic imaging source, such as a sensor device with at least one photoelectric receiver element or pixel, scans target objects moving on a conveyor belt and creates a detection signal. This detection signal can be processed by a monitoring system, which can then generate one or more pixel intensity and / or distance values. These generated intensity and / or distance values ​​can be evaluated at various time points against one or more thresholds to determine whether the target objects are moving on the conveyor belt or are stuck. In several configurations, the sensor may include, but is not limited to, a laser and an optical receiver (e.g., a single-pixel receiver and / or a linear image reader). The signal strength generated by the light received by the optical receiver (e.g., a reflected laser beam) can be determined. The sensor can then process the difference in signal strength over time to determine if an object is continuously moving on a conveyor belt. In some configurations, a distance can be measured using optical triangulation, which determines the position of an object by measuring light reflected from the target object. The sensor can then process the difference in signal strength (e.g., intensity) and / or distance over time to determine if an object is continuously moving on a conveyor belt. Figure 1 illustrates a perspective view of an example implementation of a motion detection system that implements jam detection units operating in both background and bottomless modes in an illustrative use case. A conveyor system 100 includes a conveyor 105 equipped with two jam detection units (JDUs) 110 and 120 operating in bottomless mode, and one JDU operating in background mode. 7. i bRnn / cznz / B / YiAi JDUs 110, 120, and 135 can be configured, for example, to detect the movement of objects such as target object 130 relative to conveyor 105. Therefore, various modes, for example, can usefully detect movement and / or lack of movement (e.g., a jam) of target objects on a conveyor line. JDUs 110, 120, and 135 can, for example, include both an electromagnetic signal source and an electromagnetic signal receiver. JDUs 110, 120, and 135 can, for example, be configured to emit signal 115, signal 125, and signal 140 and detect any retroreflection. In the illustrated example, JDUs 110 and 120 are configured to operate in backgroundless mode. For example, and not as a limitation, JDU 110 emits an electromagnetic signal 115 (e.g., a laser beam). No target object obstructs the beam's path, and therefore signal 115 cannot be reflected back to JDU 110. Therefore, JDU 110 can be configured to determine that the signal traveled infinitely, and there is no jamming.In a further illustration, an object outside the field of view in Figure 1, for example, can obstruct the path of signal 115, causing a reflected signal to return to JDU 110 from a foreign object rather than a target object. Therefore, JDU 110 can be configured, for example, to determine that the detected reflection corresponds to an object outside a target zone (e.g., as determined by an intensity threshold and / or distance threshold) and thus determine that no jamming exists. The JDU 120 detects a reflection of signal 125 from target object 130 and determines from this that a target object is on the conveyor. The JDU 120 can be configured to compare the received reflection at multiple time points and determine from this whether target object 130 is moving and, therefore, whether a jam state exists. Thus, various modes configured to operate in a backgroundless mode can, for example, usefully detect the presence and / or absence of a jam condition, for example, based on the application of intensity and / or distance threshold(s) to determine whether a detected signal reflection(s) correspond(s) to a predetermined detection region. The JDU 135, operating in background mode, emits an electromagnetic signal 140 that is reflected from a stationary background 145. The reflection is received back by the JDU 135. The JDU 135 can be configured, for example, with a predetermined threshold corresponding to an intensity and / or distance associated with receiving a reflection of signal 140 from the background 145. Therefore, the JDU 135 can be configured to determine that signal 140 is being reflected from the stationary background 145 and, consequently, that no target object is in front of the JDU 135 and therefore no jam exists. Consequently, various modes configured to operate in background mode can, for example, usefully detect the presence and / or absence of a jam condition, based, for instance, on... 7. i hRnn / cznz / B / YiAi the application of an intensity and / or distance threshold(s) to determine if a reflection(s) of signals correspond(s) to a predetermined stationary background. In several modes, by utilizing intensity, the JDU can advantageously provide greater robustness in discriminating between a desired motion and a jammed state, for example. The JDU can, for instance, advantageously discriminate motion not only based on distance (e.g., changes in distance between a reflecting object and a JDU receiver) but also based on changes in intensity relative to the motion of a reflected signal. For example, a substantially flat moving surface (e.g., a sheet of material) may not change substantially in distance from the JDU. However, the JDU can detect motion and discern that a jammed state does not exist based on changes in intensity (e.g., based on labels, color patterns, grayscale patterns, or changes in reflectivity). In an illustrative example, a large package (e.g., a long box) might pass a JDU monitoring a conveyor. The detected surface of the package might not change substantially with its distance from the JDU. However, the package might have markings and / or patterns. The JDU might determine that the package is moving based on changes in intensity over time, even when no significant change in distance to the reflective object is detected over time within a watchdog timer (e.g., elapsed time threshold). Figure 2 illustrates a top view of an example implementation of a motion detection system that implements a background mode in an illustrative use case. A transport system 200 includes a conveyor belt 205 bounded on the left side of the belt 205 by a stationary boundary wall 210 and on the right side by a stationary boundary wall 215. Target objects 220, 225, and 230 are placed on the belt 205. Example JDUs 235, 245, and 255 emit electromagnetic signals 240, 250, and 260, respectively, which may be, by way of example but not limitation, optical beams. Signal 240 hits target object 225 and is reflected back to JDU 235. Signal 250 hits target object 230 and is reflected back to JDU 245. Signal 260 hits stationary background 265 and is reflected back to JDU 255.The JDUs 235, 245, and 255 can be configured, for example, to determine the intensity of a reflected signal and / or to determine from a reflected signal the distance to an object that causes the associated beam to be reflected. If the target objects 220, 225, and 230 are moving upwards (relative to Figure 2) at a desired speed on the conveyor belt 205, for example, and there is no jamming condition, during a period where the time each of the JDUs 235, 245, and 255 detects 7. i hRnn / cznz / B / YiAi a reflection of the corresponding signal 240, 250, and 260, respectively, from background 265, target object 230, target object 225, and target object 220, followed by the stationary background 265 again. The JDUs can be configured, for example, to determine an intensity and / or distance value associated with the received reflection. The intensity and / or distance value can be compared, for example, with a predetermined intensity and / or distance threshold(s) that correlate(s) with a reflection of a signal from the stationary background 265. Therefore, JDUs 235, 245, and 255 can determine whether band 205 is free of target objects, at least at the monitored location.The predetermined threshold(s) may, for example, be set in a training mode (e.g., by entering a training mode, which allows a signal to be reflected from a known stationary background and by determining a threshold from this), may be set by manually entering threshold value(s) (e.g., by entering a known distance and / or intensity value), or some combination thereof. Figure 3 illustrates a top view of an example implementation of a motion detection system that implements a backgroundless mode in an illustrative use case. The transport system 201 includes a conveyor belt 205 bounded on the left side of the belt 205 by a stationary boundary wall 210 and on the right side by a stationary boundary wall 215. Target objects 220, 225, and 230 are placed on the belt 205. Example JDUs 235, 245, and 255 emit electromagnetic signals 240, 250, and 260, respectively, which may, by way of example and not limitation, be optical beams. Signal 240 strikes target object 225 and is reflected back to JDU 235. Signal 250 strikes target object 230 and is reflected back to JDU 245. Signal 260 either travels indefinitely or is reflected back to JDU 255 from a non-target object not shown in Figure 3.JDUs 235, 245, and 255 can be configured, for example, to determine the intensity of a reflected signal and / or to determine, from a reflected signal, the distance to an object causing the reflection of the associated beam. If target objects 220, 225, and 230 are moving upwards (relative to Figure 3) at a desired speed on conveyor belt 205, for example, and therefore there is no jamming condition, then over a period of time each of JDUs 235, 245, and 255 detects no reflection (or a reflection from a distant object) of the corresponding signal 240, 250, and 260, respectively, followed by a reflection from target object 230, then from target object 225, then from target object 220, followed again by no reflection or a reflection from a distant object.JDUs can be configured, for example, to determine an intensity and / or distance value associated with the received reflection. The intensity and / or distance value can be compared, for example, with a predetermined intensity and / or distance threshold(s) that correlate with a reflection of a signal. 7. i hRnn / cznz / B / YiAi from an object between one of the JDUs and wall 215. Therefore, JDUs 235, 245, and 255 can determine if any target object is present within a detection window corresponding to band 205, at least at the monitored location. The default threshold(s) can, for example, be set in a training mode (e.g., by entering a training mode, which allows a signal to be reflected from an object placed on wall 215 and by determining a threshold from there), can be set by manually entering a threshold value(s) (e.g., by entering a known distance and / or intensity value corresponding to wall 215), or some combination thereof. Figure 4 illustrates a top-level block diagram of an example jam detection circuit. A jam detection circuit 400 includes a controller 405. The controller may, for example, include a microprocessor operatively coupled with at least one data store equipped with an instruction program and configured to execute instructions to cause the motion monitoring operations to be performed. The controller 405 is operatively coupled and configured to control a transmitter 410 and a receiver 415. The transmitter 410 may be operated to emit electromagnetic signals, for example, optical beams. The transmitter 410 may, by way of example and not limitation, be an optical transmitter (for example, a laser), an ultrasonic transmitter, or some combination thereof. The receiver 415 may be operated to detect reflected electromagnetic signals, such as those emitted by the transmitter 410.The 415 receiver can, by way of example and not limitation, be an optical receiver (e.g., a photoelectric element), an ultrasonic receiver, or some combination thereof. Controller 405 is operationally coupled and configured to cause intensity motor 420, distance motor 425, and time motor 430 to perform operations. Intensity motor 420 can be operationally coupled to controller 405 and configured to determine the intensity of a reflected signal received by receiver 415. Intensity motor 420 can, for example, compare an intensity against one or more predetermined intensity thresholds. An intensity threshold can, for example, correspond to a predetermined detection window or a predetermined stationary background. Distance motor 425 can be operationally coupled to controller 405 and configured to determine a distance from a reflected signal received by receiver 415. Distance motor 425 can, for example, compare a distance against one or more predetermined distance thresholds.A distance threshold can, for example, correspond to a predetermined detection window or a predetermined stationary background. A distance motor 425 can be omitted in some modes. An intensity motor 420 can be omitted in some modes. 7. i hRnn / cznz / B / YiAi modalities. A timing motor 430 can be operationally coupled with a controller 405 and configured to monitor and determine an elapsed time since a predetermined characteristic of a reflected signal received by the receiver 415. The timing motor 430 can be configured to determine an elapsed time since a trigger has been activated, such as, by way of example and not limitation, a potential jam detection trigger activated because an attribute (or attributes) (e.g., strength and / or distance) of a received reflected signal is greater than, or less than, a predetermined threshold (or thresholds). Similarly, for example, a window between a maximum and a minimum of an attribute can be compared to a predetermined threshold, and a trigger can be activated and monitored by the timing motor 430.Therefore, several modalities can, for example, profitably detect the existence of a jamming condition by evaluating one or more attributes of the reflected signal(s) against one or more predetermined threshold(s) at a plurality of time points. Figure 5A illustrates a flowchart detailing an example motion detection process that implements a background mode. The method 500 begins by generating 505 a NO JAM signal indicating a non-jamming condition. Variables are reset 510 to default values, including a timer that can be set to zero, and a maximum and minimum intensity and / or a maximum and minimum distance that can be set to zero and infinity, respectively. A received reflection of an electromagnetic signal can be evaluated to determine 515 a corresponding intensity and / or distance.If a corresponding signal from a received reflection is detected 520, the distance and / or intensity value(s) determined in step 515 is / are compared 525 against a corresponding predetermined distance and / or intensity threshold (e.g., a predetermined window corresponding to a background such as, for example, a stationary background 145 in Figure 1 and / or a stationary background 265 in Figure 2). By way of example, and not as a limitation, an intensity greater than a predetermined intensity threshold (e.g., an intensity that is greater than an intensity window associated with a trained stationary background) may be associated with the detection of a target object between a JDU and a predetermined stationary background.If the calculated intensity value(s) and / or the calculated distance value(s) are not within the predetermined window(s) (for example, intensity greater than or equal to a predetermined intensity threshold(s) associated with the stationary background, and / or a distance less than or equal to a predetermined distance threshold(s) associated with the stationary background, respectively), the current measurements are compared with stored maximum / minimum distance and / or intensity values ​​and the running maximum / minimum values ​​are updated 530 from. 7. i hRnn / cznz / B / YiAi corresponding manner. A current intensity window and / or distance window is determined 535 by comparing the respective maximum and minimum values ​​updated in step 530. The window(s) determined in step 535 is / are compared 540 with a corresponding predetermined distance and / or intensity window threshold(s). A window below a predetermined window threshold may, by way of example and not limitation, correspond to the passage of a target object into a detection window of the JDU. For example, the window threshold may correspond to a distance difference between a specific target object at its closest position to the JDU and a gap between the specific target object and a subsequent target object. Thus, various modalities may, for example, identify a potential jam state when a predetermined window threshold is not exceeded.If the window is not larger than the corresponding default threshold, then the current elapsed time from the timer is compared to a default elapsed time threshold. If the elapsed time exceeds the threshold, a JAM signal is generated, indicating a jammed condition, for example, on a conveyor belt. By way of example, and not as a limitation, a default elapsed time threshold might correspond to the time required for a target object to move past the JDU. Therefore, various modalities can, for example, usefully implement a watchdog timer such that a potential jammed state must be detected for a predetermined amount of elapsed time before a JAM signal is generated. If a signal is not detected in step 520, the process immediately continues to compare the current elapsed time against the predetermined elapsed time threshold. By way of example, and not as a limitation, the absence of a signal in step 520 might indicate that an object is directly adjacent to a JDU face such that, for example, an emitted signal is reflected directly back to the emitter (for example, a box surface pressed directly against an emitter surface and completely blocking the emitter), so that the receiver does not receive a reflected image. Therefore, if no signal is detected, the process might, for example, treat this situation as a tentative deadlock condition and review the elapsed time without resetting the time counter at least until a signal is detected again. If the intensity value in step 525 and / or the distance value is within the default window (for example, the intensity is less than a default intensity threshold associated with the stationary background and / or the distance is greater than the default distance threshold, respectively), the process returns to step 505 to generate a NO JAM signal and subsequently resets the timer and the max / min values. 7. i hRnn / cznz / B / YiAi For example, and not as a limitation, an intensity lower than the default intensity threshold and / or a distance value greater than the default distance threshold may indicate the detection of a target object between the default stationary background and the JDU. Therefore, the JDU can be usefully configured to immediately detect a non-stuck state based on a predetermined intensity and / or distance threshold associated with a known stationary background. If the predetermined intensity and / or distance window in step 540 is determined to be greater than the predetermined window threshold(s), the process returns to step 505. By way of example, and not as a limitation, an intensity and / or distance window greater than a predetermined window threshold can be associated with a predetermined distance difference to an object reflecting an electromagnetic signal emitted between two measurements. Therefore, various modalities can, for example, be configured to usefully detect non-stuck motion by detecting a difference in distance and / or intensity between at least two time points. If the current elapsed time is not greater than the predetermined elapsed time threshold (step 545), the process returns to step 515. The timer and the maximum / minimum distance and / or intensity values ​​are not reset, and the current intensity and / or distance values ​​are determined. For example, and not as a limitation, an elapsed time not greater than the predetermined elapsed time threshold may be associated with a potential jam state that should not yet be determined as a jam condition. For example, a long box passing through may trigger the detection of a potential jam state. The predetermined time threshold may, for example, correspond to a maximum box length at a predetermined movement speed. Therefore, various modes may, for example, usefully reject false jam alarms by using a predetermined elapsed time threshold.Figure 5B illustrates a flowchart that presents in detail an example background mode training process. In an example method 501, the training process begins when a background training mode is initiated 555. The training process can, for example, be initiated by a user (e.g., by pressing a button on a JDU, or by starting it from a control console). In an example use case, for example, a JDU might be placed on one side of a conveyor belt, and a stationary background might be placed on the opposite side of the conveyor belt. The stationary background might, by way of example and not limitation, be an existing structure (e.g., a wall), a specially installed structure (e.g., an installed reflective barrier), another suitable background capable of reflecting an emitted electromagnetic signal, or some combination thereof.The JDU is then operated to launch an electromagnetic signal towards 560. 7. i hRnn / cznz / B / YiAi the predetermined stationary background, and the process determines whether a reflection of the emitted electromagnetic signal is detected 565. If the reflected signal is not detected, the emitter, receiver, and / or background are realigned 570, and the process is repeated. If a reflected signal is detected 565, a value(s) for the intensity and / or distance of the reflected signal is / are determined 575. The value(s) may, for example, be associated with the detection by a JDU of a predetermined stationary background. The value(s) determined in step 575 is / are set 580 as the predetermined intensity and / or distance threshold(s). Therefore, a JDU can determine whether a predetermined stationary background is detected and can thus quickly determine from there the possible presence of a jam state. For example, when the predetermined stationary background is detected, the JDU can immediately determine that there is no jam state. Subsequently, a window of intensity and / or distance value 585 is determined. By way of example, and not as a limitation, the window can be manually adjusted by entering default values. The window can, for example, be adjusted in an assisted training operation, where the JDU detects a maximum and a minimum range and, therefore, determines an appropriate window from there. In various modalities, the window can, by way of example, and not as a limitation, correspond to a background object location (e.g., as described with reference to 145, 265 of Figures 1-2). In the illustrated example, a window threshold with a predetermined intensity and / or distance value is then generated (590). The window threshold may correspond, for example, to the threshold applied in step 540 of method 500 described with reference to Figure 5A. The window threshold may, for example, be selected from a default value (or values), be taught during assisted training, be manually entered by a customer, or some combination thereof. The window threshold may, for example, provide a threshold for detecting motion even when a reference background is not visible. In several configurations, the window threshold can, for example and not as a limitation, correspond to the radius of a bottle (e.g., a row of bottles), a maximum width of a box, or another appropriate window. Therefore, several such configurations can, for example, be set up to usefully distinguish between individual target objects on a conveyor. In several configurations, the training operation can also include teaching an elapsed time threshold. An elapsed time threshold can, for example and not as a limitation, be taught through a stopwatch mechanism configured to determine (e.g., by a user specifying a start and stop time) an elapsed time for a target object to pass through the JDU. Figure 6A illustrates a flowchart that presents a detailed example process 7. i hRnn / cznz / B / YiAi motion detection that implements a backgroundless mode. Method 600 begins by generating 605 a NO JAM signal indicating a non-jammed condition. The variables are reset 610 to their default values, including a timer that can be set to zero, and a maximum and minimum intensity and / or a maximum and minimum distance that can be set to zero and infinity, respectively. A received reflection of an electromagnetic signal can be evaluated to determine 615 a corresponding intensity and / or distance. If a signal corresponding to a received reflection is detected 620, the distance and / or intensity value(s) determined in step 615 is / are compared 625 against a corresponding predetermined distance and / or intensity threshold (e.g., intensity and / or distance window, as illustrated, corresponding to a region of interest).By way of example and not limitation, an intensity greater than or equal to a predetermined intensity threshold (e.g., associated with the detection of a target object within a predetermined detection zone from the JDU) and / or a distance less than or equal to a predetermined distance threshold (e.g., associated with a target object within a predetermined distance from the JDU) may be associated with the detection of a target object between a JDU and a predetermined distance from the JDU. If the calculated intensity value(s) and / or the calculated distance value(s) are within the predetermined window (for example, intensity greater than or equal to a predetermined threshold(s) corresponding to a maximum distance from the sensor of a predetermined detection zone and / or a distance less than or equal to a predetermined threshold(s) corresponding to a maximum extent of a predetermined detection zone), the current measurements are compared with stored maximum / minimum distance and / or intensity values, and the running maximum / minimum values ​​are updated accordingly. A current intensity window and / or distance window is determined by comparing the respective maximum and minimum values ​​updated in step 630.The window(s) determined in step 635 is / are compared 640 with a corresponding predetermined distance and / or intensity window threshold(s). A window below a predetermined window threshold may, by way of example and not limitation, correspond to the passage of a target object into a JDU detection window. For example, the window threshold may correspond to a distance difference between a specific target object at its closest position to the JDU and a gap between that specific target object and the next target object. Therefore, various modalities may, for example, identify a potential jam state when a predetermined window threshold is not exceeded. If the window is not larger than the corresponding default threshold, then a time 7. The current elapsed time of the timer is compared 645 with a predetermined elapsed time threshold. If the elapsed time exceeds a threshold, a JAM signal is generated 650 indicating a jammed condition, for example, on a conveyor belt. By way of example, and not as a limitation, a predetermined elapsed time threshold could correspond to the time required for a target object to move past the JDU. Consequently, various modalities can, for example, usefully implement a watchdog timer such that a potential jammed state must be detected for a predetermined amount of elapsed time before a JAM signal is generated. If a signal is not detected in step 620, the process immediately proceeds to step 605 to produce a NO JAM signal. For example, and not as a limitation, the absence of a signal in step 620 could indicate that no object is in front of the JDU, such that, for instance, an emitted signal travels indefinitely without being reflected (e.g., in a warehouse), and the receiver receives no reflected image. Therefore, if no signal is detected, the process treats this situation as a non-jam condition. If the intensity value in step 625 and / or the distance value is not within the default window (for example, intensity less than the default intensity threshold and / or distance greater than the default distance threshold), the process returns to step 605 to generate a NO JAM signal and subsequently resets the timer and the max / min values. By way of example, and not as a limitation, an intensity and / or distance value within a default window (for example, greater than the default intensity threshold and / or less than the default distance threshold, respectively) may indicate that the JDU has detected a target object within a default detection zone.Therefore, the JDU can be advantageously configured to immediately detect a non-jamming state based on a predetermined window of distance and / or intensity (e.g., at least one threshold) associated with a position outside a predetermined detection window (e.g., a conveyor belt width). If the intensity and / or distance window determined in step 640 is found to be greater than the predetermined window threshold(s), the process returns to step 605. By way of example, and not as a limitation, an intensity and / or distance window greater than a predetermined window threshold can be associated with a predetermined distance difference to an object reflecting an electromagnetic signal emitted between two measurements. Therefore, various modes can, for example, be configured to usefully detect non-stuck motion by detecting a difference in distance and / or intensity between at least two time points. 7. i hRnn / cznz / B / YiAi If the current elapsed time is not greater than the predetermined elapsed time threshold (step 645), the process returns to step 615. The timer and the maximum / minimum distance and / or intensity values ​​are not reset, and the current intensity and / or distance values ​​are determined (step 615). By way of example, and not as a limitation, an elapsed time not greater than the predetermined elapsed time threshold may be associated with a potential jam state that should not yet be determined as a jam condition. For example, a long box may be passing through, triggering the detection of a potential jam state. The predetermined time threshold may, for example, correspond to a maximum box length at a predetermined movement speed. Therefore, various modes may, for example, usefully reject false jam alarms by using a predetermined elapsed time threshold. Figure 6B illustrates a flowchart that shows in detail an example backgroundless mode training process. In an example method 601, the training process begins when a backgroundless training mode is initialized 655. The training process can, for example, be initiated by a user (e.g., by pressing a button on a JDU, or by initialization from a control console). In an example use case, for instance, a JDU might be positioned on one side of a conveyor belt and oriented to emit a beam across the belt and substantially parallel to one of its carrying surfaces.The JDU may, by way of example and not limitation, in the absence of a target object on the conveyor belt, receive no reflected signal and / or receive a reflection caused by an emitted signal that is reflected from an object not on the conveyor belt (e.g., a distant object, wall, person, vehicle). A time limit may be placed to define a predetermined detection zone (e.g., on the opposite side of the conveyor belt from the JDU). The JDU is then operated to emit an electromagnetic signal toward the time limit. In some modalities, a user and / or additional steps in a circuit-implemented process may determine, for example, whether a reflection of the emitted electromagnetic signal is detected. If no reflected signal is detected, the emitter, receiver, and / or limit may be realigned, and the process is repeated. An intensity and / or distance value(s) for a reflection of the electromagnetic signal is determined (675). The value(s) may, for example, be associated with the JDU's detection of an object within a predetermined detection zone. The value(s) determined in step 675 is / are set (680) as a predetermined intensity and / or distance threshold(s). Therefore, a JDU can determine whether a target object is detected within a predetermined detection zone and, consequently, can quickly determine from this whether a potential jamming state may not exist and / or whether a signal from a reflection is present. 7. The detected hRnn / pznz / Β / γΐΛΐ should be rejected because it is caused by an object outside the predetermined detection zone. For example, when no reflection is detected, or when a reflection is detected that comes from outside the predetermined detection zone, the JDU can immediately determine that there is no jam state. Subsequently, a window of intensity and / or distance value 685 is determined, for example, as discussed in relation to step 585 of Figure 5B. In the illustrated example, a window threshold of intensity and / or distance value 690 is generated (for example, as described with reference to step 590 of Figure 5B). The window threshold may, for example, correspond to the default threshold of step 640 described with reference to Figure 6A. In various modes, the window threshold may, for example, be selected from a default value(s), be trained during an assisted training operation, be manually entered by a customer, or some combination thereof. The window threshold may, for example, provide a threshold for detecting motion even when an object is detected (for example, a reflected electromagnetic signal is received).In several configurations, an elapsed time threshold can, for example, be determined in accordance with the discussion in relation to Figure 5B. Although several configurations have been described with reference to the figures, other configurations are possible. For example, even though an example system has been described with reference to the figures, other implementations can be deployed in other industrial, scientific, medical, commercial, and / or residential applications. For example, even though distance and / or intensity windows have been described in the context of maximum-to-minimum windows (e.g., ranges), such as 535 in Figure 5A and 635 in Figure 6A, other windows can be generated. As an illustrative example, a window can be generated based on a standard deviation and / or other statistical analysis. In some configurations, for example, a first-in, first-out buffer can store N samples. A (predefined) analysis can be performed on M (where M < N) of the N samples. The N samples can, for example, include the current intensity and / or distance sample. The predefined analysis can include a statistical analysis. A window can be generated based on a predefined multiplier of one standard deviation of the M samples. For example, even though several predefined thresholds have been described as being in a user-defined environment, a user can set a threshold configuration in a training mode (e.g., a learning mode) of the monitoring system. For example, a JDU can generate and store one or more threshold configurations. Beneficial results can be achieved if the threshold configuration is automatically adjusted by the JDU (e.g., by a monitoring module) after the 7. i hRnn / cznz / B / YiAi Initial configuration to calibrate a threshold setting more accurately. For example, the JDU can calibrate a threshold based on temperature. The JDU can calibrate a threshold, for example, based on ambient light. The JDU can, for example, update a threshold based on user feedback (for example, indicating a jammed or non-jammed state, such as agreeing or disagreeing with a state currently produced by the JDU). In one useful example modification, a JDU can be configured for training criteria that identify a motion state, set the learned criteria as a baseline for motion detection, and / or automatically calibrate a threshold based on the learned criteria. In another useful mode, the JDU can be configured to allow both a user-defined threshold and a machine-learned threshold. Although several configurations have been discussed here in relation to integrated JDUs, other configurations are possible. For example, various jam detection systems may include a combination of separate and / or integrated sensors, emitters, and controllers. While several configurations have been discussed here in relation to individual JDUs, JDUs can be chained or otherwise associated. By way of example, and not as a limitation, one or more thresholds (e.g., intensity, distance, and / or time) can be configured to be applied to a combination of signals from one or more JDUs. For example, a controller can be configured to determine whether a JAM signal is generated based at least partially on a comparison of signals from multiple JDUs.By way of example, and not as a limitation, a non-stuck state can be detected by comparing reflections received by two spatially separated JDUs. Therefore, various methods can, for example, effectively reduce false jam alarms and / or more quickly identify a jammed condition. In some embodiments, various computer system circuits and / or environments (e.g., jam detection circuit 400) may include fewer or more components (e.g., than those discussed in relation to Figure 4) to perform the described method(s). For example, the computing system and devices may include various combinations of hardware and / or software capable of performing the indicated functions. Such components may, by way of example and not limitation, include computers, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), network devices, and / or Internet applications, including, for example, and without limitation, web-based applications. A computer system environment may, for example, be connected to other devices not illustrated.A computer system environment can, for example, operate as a standalone system. In some configurations, functionalities provided by various components (illustrated here) can, by way of example and not necessarily. 7. i hRnn / cznz / B / YiAi limiting, combine with fewer components. In some modalities, for example, a functionality may be distributed across additional components. In some modalities, for example, the functionality of some of the illustrated components may not be provided and / or additional functionalities may be available. While several elements are typically stored in memory or a data store, in some configurations these elements or portions of them can be transferred between memories and other storage devices, for example, for memory management and data integrity. In some configurations, some or all of the software components can run in memory on another device and communicate with the computer system being represented via computer-to-computer communication. In various configurations, some shunt circuit implementations can be controlled in response to signals from analog or digital components that may be discrete, integrated, or a combination thereof. In some configurations, they may include programmed devices, programmable devices, or some combination thereof (e.g., PLAs, PLDs, ASICs, microcontrollers, microprocessors) and may include one or more data stores (e.g., cells, registers, blocks, pages) that provide single- or multi-level digital data storage capacity and that may be volatile, non-volatile, or some combination thereof. Some control functions may be implemented in hardware, software, firmware, or a combination thereof. Computer program products may contain a set of instructions that, when executed by a processing device, cause the processor to perform prescribed functions. These functions may be performed in conjunction with controlled devices in operational communication with the processor. Computer program products, which may include software, may be stored in a data store tangibly embedded in a storage medium, such as an electronic, magnetic, or rotating storage device, and may be fixed or removable (e.g., hard disk, floppy disk, flash memory, CD, DVD). Although an example of a system that can be portable has been described with reference to the figures above, other implementations can be deployed in other processing applications, such as desktop computers or network environments. Temporary auxiliary power inputs can be obtained, for example, from rechargeable or disposable batteries, enabling use in portable or remote applications. Some models can operate on DC power sources, such as 9V (nominal) batteries. Alternating current (AC) inputs, which can be supplied, for example, from a 50 / 60 Hz power supply port or a portable generator, can also be used. 7. i hRnn / cznz / B / YiAi to be received through a rectifier and appropriate scaling. Provision for AC inputs (e.g., sine wave, square wave, triangle wave) may include a line frequency transformer to provide voltage boost, voltage step-down, and / or isolation. Even though specific architectural features have been described, other features can be incorporated to improve performance. For example, caching techniques (e.g., L1, L2, etc.) can be used. Random access memory (RAM) can be included, for example, to provide a notepad memory and / or to load executable code or stored parameter information for use during runtime operations. Other hardware and software can be provided to perform operations, such as networking or other communications using one or more protocols, wireless communications (e.g., infrared), stored operating energy and power supplies (e.g., batteries), switching circuits and / or linear power supplies, software maintenance (e.g., self-testing, updates), and the like.One or more communication interfaces may be provided to support data storage and related operations. Some systems can be implemented as a computer system that can be used with various implementations. For example, various implementations might include digital circuitry, analog circuitry, hardware, firmware, computer software, or a combination thereof. Devices can be implemented as a computer program product tangibly embedded in a data storage medium, such as a machine-readable storage device, for execution by a programmable processor; and methods can be performed by a programmable processor executing a program of instructions to perform functions of various modes by operating on input data and generating output.Several methods can be profitably implemented in one or more computer programs that are executable on a programmable system that includes at least one programmable processor coupled to receive data and instructions from a data storage system and to transmit data and instructions to that system, at least one input device, and / or at least one output device. A computer program is a set of instructions that can be used, directly or indirectly, on a computer to perform a certain activity or to produce a certain result. A computer program can be written in any programming language, including compiled or interpreted languages, and can be deployed in any form, including as a standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. Processors suitable for executing a program of instructions include, by way of example, both general-purpose microprocessors and special-purpose microprocessors, 7. i hRnn / cznz / B / YiAi which may include a single processor or one of multiple processors of any type of computer. Generally speaking, a processor will receive instructions and data from read-only memory or random-access memory, or both. The essential elements of a computer are a processor to execute instructions and one or more memories to store instructions and data. Generally speaking, a computer will also include, or be operationally coupled to communicate with, one or more mass storage devices to store data files; such devices include magnetic disks, such as internal hard drives and removable disks; magneto-optical disks; and optical disks.Suitable storage devices for tangibly incorporating computer program instructions and data include all forms of non-volatile memory, including, for example, semiconductor memory devices such as EPROM, EEPROM, and flash memory devices; magnetic disks such as internal hard drives and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM discs. The processor and memory may be supplemented by or integrated into ASICs (application-specific integrated circuits). In some implementations, each system can be programmed with the same or similar information and / or initialized with substantially identical information stored in volatile and / or non-volatile memory. For example, a data interface can be configured to perform self-configuration, self-download, and / or update functions when attached to an appropriate host device, such as a desktop computer or server. In some implementations, one or more user interface features can be custom-configured to perform specific functions. Various modalities can be implemented on a computer system that includes a graphical user interface and / or an internet browser. To provide user interaction, some implementations can be deployed on a computer that has a display device, such as a CRT (cathode ray tube) or LCD (liquid crystal display) monitor to visually present information to the user, a keyboard, and a pointing device, such as a mouse or trackball, through which the user can provide input to the computer. In various implementations, the system can communicate using appropriate communication methods, equipment, and techniques. For example, the system can communicate with compatible devices (e.g., devices capable of transferring data to and / or from the system) using point-to-point communication, in which a message is carried directly from the source to the receiver over a dedicated physical link (e.g., fiber optic link, point-to-point wiring, daisy chain). System components can exchange information. 7. i hRnn / cznz / B / YiAi in any form or on any analog or digital data communication medium, including packet-based messages on a communication network. Examples of communication networks include, for instance, a LAN (local area network), a WAN (wide area network), a MAN (metropolitan area network), wireless and / or optical networks, the computers and networks that make up the Internet, or some combination thereof. Other implementations may carry messages by broadcast to all, or substantially all, devices coupled together by a communication network, for example, by using omnidirectional radio frequency (RF) signals. Other implementations may carry messages characterized by high directivity, such as RF signals transmitted using directional antennas (i.e., narrowband) or infrared signals that may optionally be used with focusing optics.Other implementations are possible that utilize appropriate interfaces and protocols, such as, but not limited to, USB 2.0, FireWire, ATA / IDE, RS-232, RS422, RS-485, 802.11 a / b / g, Wi-Fi, Ethernet, IrDA, FDDI (Fiber Distributed Data Interface), token ring networks, frequency division, time division, or code division multiplexing techniques, or some combination thereof. Some implementations may optionally incorporate features such as error checking and correction (ECC) for data integrity, or security measures such as encryption (e.g., WEP) and password protection. In various configurations, a computer system can include Internet of Things (IoT) devices. IoT devices can include objects integrated with electronics, software, sensors, actuators, and network connectivity that allow these objects to collect and exchange data. IoT devices can be used with wired or wireless devices by sending data through an interface to another device. IoT devices can collect useful data and then autonomously transmit that data between other devices. Various examples of modules can be implemented using circuitry, including various electronic hardware components. By way of example, and without limitation, the hardware may include transistors, resistors, capacitors, switches, integrated circuits, other modules, or some combination thereof. In some examples, the modules may include analog logic, digital logic, discrete components, traces, and / or memory circuits fabricated on a silicon substrate that includes various integrated circuits (e.g., FPGAs, ASICs) or some combination thereof. In some embodiments, the module(s) may involve the execution of pre-programmed instructions, software executed by a processor, or some combination thereof. For example, some modules may include both hardware and software. For illustrative purposes, a contactless motion detection monitoring system can 7. i hRnn / cznz / B / YiAi include a processor. The monitoring system may include an electromagnetic imaging source. The electromagnetic imaging source may include a receiver element configured by the processor to generate an intensity signal (e.g., 515, 615) based on the intensity of a reflected electromagnetic signal. The monitoring system may include a data store operatively coupled with the processor and containing instructions that, when executed by the processor, cause the processor to perform operations to detect an object's motion state. The operations may include, in response to the detection of the reflected electromagnetic signal (e.g., 515, 615), comparing the intensity signal to a predetermined intensity threshold (e.g., 525, 625).The operation may include, if the intensity signal is greater than or equal to the intensity threshold, then determining an intensity window metric by comparing the intensity threshold with at least one stored intensity value (for example, 535, 635). Operations may also include determining if the intensity window metric is greater than a predetermined intensity window threshold (for example, 540, 640). Furthermore, operations may include, if the intensity window metric is not greater than the intensity window threshold and the time elapsed since a historical intensity window metric exceeded the intensity window threshold is greater than a predetermined elapsed time threshold (for example, 545, 645), then generating a signal indicating a jammed state (for example, 550, 650). Operations may include, if no reflected electromagnetic signal is detected (e.g., 515) and if the time elapsed since a historical intensity window metric exceeded the intensity window threshold is greater than the elapsed time threshold (e.g., 545), then generating the signal indicating the jammed state (e.g., 550, 650). The operations may include, if the intensity signal is within the intensity threshold (e.g., 525), then generating a signal indicating a non-stuck state (e.g., 505). The receiver may also be configured to generate a distance signal from the reflected electromagnetic signal. The operations may include comparing the distance signal to a predetermined distance threshold (e.g., 525). The operations may include, if the distance signal is within the distance threshold (e.g., 525), then generating a signal indicating a non-stuck state (e.g., 505). The operations may include, if the intensity signal is outside the intensity threshold (e.g., 625), then generating a signal indicating a non-stuck state (e.g., 605). The receiving element may be configured to generate a distance signal from the reflected electromagnetic signal. Operations may include comparing the distance signal to a predetermined distance threshold (e.g., 625). Operations may include, if the distance signal is outside the distance threshold (e.g., 625), then generating a signal that 7. i hRnn / cznz / B / YiAi indicates a non-stuck state (e.g., 605). Operations may include, if the intensity window metric is outside the intensity window threshold (e.g., 540, 640), then generating a signal indicating a non-stuck state (e.g., 505, 605). The operations may include, if the elapsed time is less than the elapsed time threshold (e.g., 545, 645), then repeating the operations. The operations may include, if the reflected electromagnetic signal is not detected (e.g., 615, 620), then generating a signal indicating a non-stuck state (e.g., 605). The operations may include intensity threshold presetting operations to generate a predetermined intensity threshold. Intensity threshold presetting operations may include providing a predetermined object such that an electromagnetic signal directed at that object generates the electromagnetic signal reflected back to the receiver. Intensity threshold presetting operations may include, in response to the detection of the reflected electromagnetic signal (e.g., 565, 665), determining the intensity value of the reflected electromagnetic signal (e.g., 575, 675). Intensity threshold presetting operations may include generating the intensity threshold from the intensity value. Intensity threshold presetting operations may include determining an intensity value window.The intensity threshold presetting operations may include generating a default intensity window threshold. Operations to detect an object's movement state may include, in response to the generation of a signal indicating a non-stuck state, then resetting the elapsed time to zero. The intensity threshold can be set to correspond to a predetermined maximum distance from the receiving element. The intensity threshold can be set to correspond to a predetermined stationary physical background. Imaging using an electromagnetic wave beam may include a laser source. The receiving element may include at least one photoelectric sensor. The monitoring system may include an application-specific integrated circuit (ASIC). The ASIC may include an interface for connection to the processor. The ASIC may include circuitry for controlling processor operations. For illustrative purposes, a contactless motion detection method configured to detect the motion state of objects may include generating, by a receiver of an electromagnetic imaging source, an intensity signal (e.g., 515, 615) based on the intensity of a reflected electromagnetic signal. The method may include, in 7. i hRnn / cznz / B / YiAi response to the detection of the reflected electromagnetic signal (e.g., 515, 615), compare the intensity signal with a predetermined intensity threshold (525, 625). The method may include, if the intensity signal is greater than or equal to the intensity threshold, then determining an intensity window metric from a comparison of the intensity threshold with at least one stored intensity value (e.g., 535, 635). The method may also include determining if the intensity window metric is greater than a predetermined intensity window threshold (e.g., 540, 640).The method may include, if the intensity window metric is not greater than the intensity window threshold and if the time elapsed since a historical intensity window metric exceeded the intensity window threshold is greater than a predetermined elapsed time threshold (e.g., 545, 645), then generating a signal indicating a jammed state (e.g., 550, 650). The method may include generating, by the receiving element, a distance signal from the reflected electromagnetic signal. The method may include, in response to the detection of the reflected electromagnetic signal (e.g., 515, 615), comparing the distance signal with a predetermined distance threshold (e.g., 525). The method may include, if the distance signal is within the distance threshold (e.g., 525), then generating a signal indicating a non-stuck state (e.g., 505). The method may include generating, by the receiving element, a distance signal from the reflected electromagnetic signal. The method may include, in response to the detection of the reflected electromagnetic signal (e.g., 515, 615), comparing the distance signal with a predetermined distance threshold (e.g., 625). The method may include, if the distance signal is outside the distance threshold (e.g., 625), then generating a signal indicating a non-stuck state (e.g., 605). Several implementations have been described. However, it is understood that various modifications are possible. For example, beneficial results may be achieved if the steps of the disclosed techniques are carried out in a different sequence, or if components of the disclosed systems are combined differently, or if the components are supplemented with other components. Therefore, other implementations are contemplated within the scope of the following claims.

Claims

1. A contactless motion detection monitoring system comprising: a processor; an electromagnetic imaging source comprising a receiver element configured by the processor to generate an intensity signal (515, 615) based on the intensity of a reflected electromagnetic signal; and a data store operatively coupled to the processor and containing instructions that, when executed by the processor, cause the processor to perform operations to detect an object motion state, the operations comprising: in response to the detection of the reflected electromagnetic signal (515, 615), comparing the intensity signal with a predetermined intensity threshold (525, 625);If the intensity signal is greater than or equal to the intensity threshold, then determine an intensity window comparison metric from a comparison of the intensity signal with at least one stored intensity value (535, 635); determine if the intensity window comparison metric is greater than a predetermined intensity window threshold (540, 640); and, if the intensity window comparison metric is not greater than the intensity window threshold and if the time elapsed since a historical intensity window metric last exceeded the intensity window threshold is greater than a predetermined elapsed time threshold (545, 645), then generate a signal indicating a jammed state (550, 650).

2. The monitoring system according to claim 1, wherein if the reflected electromagnetic signal is not detected (515) and if a time elapsed since a historical intensity window metric exceeded the intensity window threshold is greater than the elapsed time threshold (545), then generate the signal indicating the jammed state (550, 650).

3. The monitoring system according to claim 1, wherein if the intensity signal is within the intensity threshold (525), then generate a signal indicating a non-stuck state (505).

4. The monitoring system according to claim 1, wherein: the receiving element is further configured to generate a distance signal from the reflected electromagnetic signal; and the operations further comprise: comparing the distance signal with a predetermined distance threshold (525); and, if the distance signal is within the distance threshold (525), then generating a signal indicating a non-stuck state (505).

7. i hRnn / cznz / B / YiAi 5. The monitoring system according to claim 1, wherein if the intensity signal is outside the intensity threshold (625), then generate a signal indicating a non-stuck state (605).

6. The monitoring system according to claim 1, wherein: the receiving element is further configured to generate a distance signal from the reflected electromagnetic signal; and the operations further comprise: comparing the distance signal with a predetermined distance threshold (625); and, if the distance signal is outside the distance threshold (625), then generating a signal indicating a non-stuck state (605).

7. The monitoring system according to claim 1, wherein if the intensity window metric is outside the intensity window threshold (540, 640), then generate a signal indicating a non-stuck state (505, 605).

8. The monitoring system according to claim 1, wherein if the elapsed time is less than the elapsed time threshold (545, 645), then repeat the operations.

9. The monitoring system according to claim 1, wherein if the reflected electromagnetic signal is not detected (615, 620), it generates a signal indicating a non-stuck state (605).

10. The monitoring system according to claim 1, further comprising intensity threshold predetermination operations to generate a predetermined intensity threshold, the intensity threshold predetermination operations comprising: providing a predetermined object such that an electromagnetic signal launched towards it generates the reflected electromagnetic signal towards the receiver; in response to the detection of the reflected electromagnetic signal (565, 665), determining the intensity value of the reflected electromagnetic signal (575, 675); and generating the intensity threshold therefrom.

11. The monitoring system according to claim 10, wherein the intensity threshold predetermination operations further comprise: determining an intensity value window; and generating a predetermined intensity window threshold.

12. The monitoring system according to claim 1, further comprising, in response to the generation of a signal indicating a non-stuck state, then resetting the elapsed time to zero.

13. The monitoring system according to claim 1, wherein the intensity threshold is configured to correspond to a predetermined maximum distance from element 7. i hRnn / cznz / B / YiAi receiver.

14. The monitoring system according to claim 1, wherein the intensity threshold is configured to correspond to a predetermined stationary physical background.

15. The monitoring system according to claim 1, wherein the electromagnetic image source comprises a laser source.

16. The monitoring system according to claim 1, wherein the receiving element comprises at least one photoelectric sensor.

17. The monitoring system according to claim 1, further comprising an application-specific integrated circuit (ASIC) comprising: an interface for connection to the processor, and circuitry for controlling the processor operations.

18. A method for contactless motion detection configured to detect a motion state of objects, the method comprising: generating, by the receiving element of an electromagnetic imaging source, an intensity signal (515, 615) as a function of a reflected electromagnetic signal intensity; in response to the detection of the reflected electromagnetic signal (515, 615), comparing the intensity signal with a predetermined intensity threshold (525, 625); if the intensity signal is greater than or equal to the intensity threshold, then determining an intensity window comparison metric from a comparison of the intensity threshold with at least one stored intensity value (535, 635); determining whether the intensity window comparison metric is greater than a predetermined intensity window threshold (540, 640);and, if the intensity window comparison metric is not greater than the intensity window threshold and if a time elapsed since a historical intensity window metric last exceeded the intensity window threshold is greater than a predetermined elapsed time threshold (545, 645), then generate a signal indicating a jammed state (550, 650).; 19. The method according to claim 18, further comprising: generating, by the receiving element, a distance signal from the reflected electromagnetic signal; in response to the detection of the reflected electromagnetic signal (515, 615), comparing the distance signal with a predetermined distance threshold (525); if the distance signal is within the distance threshold (525), then generating a signal indicating a non-stuck state (505).

20. The method according to claim 18, further comprising:

7. i hRnn / cznz / B / YiAi generating, by the receiving element, a distance signal from the reflected electromagnetic signal; in response to the detection of the reflected electromagnetic signal (515, 615), comparing the distance signal with a predetermined distance threshold (625); and 5 if the distance signal is outside the distance threshold (625), then generating a signal indicating a non-stuck state (605).

Images