Methods and systems for determination and classification of intoxicants in breath samples facilitated by user interaction schemes

Abstract

The present invention relates to a breath analysis system and method. In particular, the present invention relates to a breath analysis system and method arranged to provide a tracer assisted determination and classification of the presence of a respiratory intoxicant facilitated by a user interaction protocol. If the determination can not be performed within a first compliance mode of operation, an interactive mode is initiated in which the user is stepwise instructed to perform actions that facilitate the classification. An action compliance value indicative of how well the user followed the issued actions / instructions is determined and used to select actions.

Description

Technical Field

[0001] This invention relates to a respiratory analysis system and method. More specifically, this invention relates to a respiratory analysis system and method arranged to provide tracer-assisted determination and classification of the presence of respiratory narcotic substances facilitated by a user interaction scheme. Background Technology

[0002] Breathalyzer equipment is becoming increasingly common, primarily as a means of detecting and preventing driving under the influence of narcotic substances (especially ethanol) in vehicles. Breathalyzer equipment can be a standalone (or even handheld) unit that provides measurements of the levels of one or more substances in a driver's breath. Alternatively, breathalyzer equipment can be part of a system that also includes devices for identifying the driver and / or stationarying the vehicle. Such breathalyzer equipment is typically permanently installed in the vehicle and can be, for example, an integral part of the dashboard. Breathalyzer equipment can also be a stationary system for controlling access to work areas, fleet depots, etc.

[0003] Providing a breath analyzer with appropriate sensitivity, reliability, and reasonable speed of analysis is no small matter. This is especially true if the breath analysis equipment should be able to detect multiple substances and be unaffected by changes in humidity, CO2 levels, etc. Breath analysis equipment that meets these requirements is described, for example, in US7919754 and US9746454, which are incorporated herein by reference.

[0004] Breathalyzer equipment can be part of a system that also includes devices for identifying the driver and / or immobilizing the vehicle—the so-called "alcohol interlock." This breathalyzer equipment is typically permanently installed in the vehicle and can be, for example, an integral part of the dashboard, connected to the vehicle's control system. Alcohol interlocks are widely used in offender procedures as a mandatory accessory for the rehabilitation of car owners convicted of drunk driving. Similar systems and devices are also being used in commercial transportation such as buses, taxis, and trains. However, these systems appear poised to become prevalent in private transportation in the near future, and may even be mandatory in at least some countries and regions.

[0005] The most common method to date for installing breathalyzer testing equipment in vehicles is through a mouthpiece. After taking a deep breath, the user is required to clear their airway to the mouthpiece. This method is called active testing. To ensure accurate detection, the user should deliver a forced exhale at almost full lung capacity. This requires a significant amount of time and effort, especially for those with limited lung capacity. Additionally, for hygiene reasons, mouthpieces or parts thereof are often made of single-use plastic. This leads to cumbersome disposal and the use of a large quantity of single-use plastics, a situation that would arise if alcohol lockouts became mandatory, which is problematic from an environmental perspective.

[0006] An alternative approach is called contactless detection, in which no mouthpiece is used, and the breathalyzer test device typically receives a mixture of exhaled breath and ambient air, and determines the detection of the stimulant substance based on a breath sample taken during exhalation in normal breathing. This detection can be truly passive, requiring no action from the user, such as occurring when the user performs a routine vehicle start-up procedure. Alternatively, the user can be instructed to perform certain actions intended to facilitate the detection process, for example, the user can be instructed to breathe towards the air inlet, etc. Even when the user is instructed to breathe in a certain direction, etc., a challenge with contactless detection is the low concentration of the substance to be detected and analyzed. The established approach is to utilize a tracer gas (typically carbon dioxide or water vapor) that is always present in breath in highly predictable amounts to both trigger the analysis of the target substance and facilitate the determination of its concentration value. However, it has proven difficult to make contactless detection work satisfactorily in real-life scenarios. Even if the data indicating the presence or absence of the stimulant substance is ultimately correctly analyzed, the time required for such classification is too long and unacceptable in vehicles where alcohol locks prevent the vehicle from operating until, for example, approval is given. Therefore, there is a need for systems and methods that provide faster and more reliable feedback to users / drivers, and in particular, measurement errors must be handled effectively.

[0007] Co-pending application SE 2050105-2 by the same applicant as this invention discloses a respiratory analysis system and method arranged to provide rapid tracer-assisted classification of the presence of respiratory narcotic substances above a threshold concentration, and to provide the user with status updates related to the classification progress. SE 2050105-2 is incorporated herein by reference.

[0008] US 7,736,903 discloses a system and method for passively detecting alcohol using first and second tracers and first and second time periods for compensating for environmental changes. The response time for such systems is typically several minutes, which is considered far too slow for practical use in both automotive and other applications.

[0009] US 8,377,705 discloses the addition of another tracer, water vapor, and another detection mode, wherein ethanol and tracer signals are measured at a first time and a second time, different from the first time. However, no mention is made of how to avoid or manage measurement errors, and response time also appears to be an issue in this system / method.

[0010] US 2020 / 101982 relates to a breath alcohol sensor / analyzer, a microphone / voice discrimination unit, and a speaker / voice synthesizer. The voice synthesizer generates questions to be answered orally by the subject, thereby producing an airflow detectable by the breath analyzer. The analysis results determine the drivability of a vehicle. Issues related to ambiguous or invalid sensor data remain unresolved. Such ambiguity may arise from signal interference, out-of-range environmental conditions, technical errors, or poor subject cooperation. The latter reason is considered dominant.

[0011] Therefore, there remains a need to improve breathalyzer equipment in vehicles to gain widespread acceptance for this technology. Most importantly, the test must be quick and reliable for an alert driver / user who follows instructions on how to perform the test. Ideally, the test should not add any manual operation or cause any time delay in starting the vehicle for an alert and compliant driver / user. Summary of the Invention

[0012] The purpose of this invention is to provide a respiratory analysis system and operating method that overcomes the shortcomings of existing passive detection systems.

[0013] This is achieved by the method as defined in claim 1 and the respiratory analysis system as defined in claim 13.

[0014] According to one aspect of the invention, a method is provided for operating a respiratory analysis system to determine a constraint level for the user based on an analysis of the concentration of narcotic substances in the exhaled breath of a user performing a specified task and the user's behavior. The method includes a compliance operating mode and an interactive operating mode, and the method utilizes a predetermined set of constraint levels and a predetermined set of actions.

[0015] The compliance pattern includes the following steps:

[0016] - Sample the signal representing the local concentration of the narcotic substance, analyze the sampling results, and determine, based on the analysis results, whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision;

[0017] -If the category is determined to be potentially executable, then:

[0018] - Determine the respiratory concentration of the narcotic substance, and

[0019] - The inhalation concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level.

[0020] If the classification is determined to be impossible to execute, the method enters the interactive operation mode, which includes the following steps:

[0021] - The user is issued a selected action from a predetermined set of actions. The selection of the action is based on a session history log and an action compliance value, wherein the session history log includes information related to the selected actions issued in the current interactive mode session and the corresponding results of the issued selected actions, and the action compliance value is a value determined based on the result of the issued selected action. The result of the issued selected action may be an improved determination of the respiratory concentration of the narcotic substance or an output from an auxiliary sensor;

[0022] - The signal representing the local concentration of the narcotic substance is sampled and the sampling results are analyzed, and the results are used to determine whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision.

[0023] -If classification is determined to be possible, then:

[0024] - Determine the respiratory concentration of the narcotic substance, and

[0025] - Compare the inhaled concentration of the narcotic substance with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; and

[0026] If the classification is determined to be impossible, then:

[0027] - Determine the action compliance value based on an analysis of how well the user has complied with the selected action issued;

[0028] - Update the session history log, which includes at least information about which action from the predetermined action set has been issued;

[0029] - Repeat the steps in interactive mode until the constraint level is established.

[0030] The steps may be repeated, either alternatively or in combination, until a predetermined maximum time period is reached.

[0031] According to one embodiment of the method, the set of constraint levels includes multiple constraint levels representing increased restrictions on the drivability of the vehicle. The set of constraint levels may include one or more of the constraint levels corresponding to the settings of the vehicle: unconstrained driving, driving with issued warnings, limited drivability, and ignition lock.

[0032] According to one embodiment of the method, the predetermined set of actions includes at least one subset of: attention actions, directive actions, requests for actions, and warning actions. Attention actions may include activating a visually appealing element.

[0033] According to one embodiment of the method, the interaction unit is used by the respiratory analysis system to transmit the selected action to the user.

[0034] According to one embodiment of the method, the steps include a further step to be taken when the selected action is issued, the further step including receiving confirmation from the user that the user understands and accepts the selected action.

[0035] According to one embodiment of the method, the action compliance value is based on an analysis of the likelihood that the measurement of the narcotic substance has improved the classification within the desired level of accuracy and precision. Alternatively or in combination, the determined action compliance value is based at least in part on input provided by the auxiliary sensing unit.

[0036] According to one aspect of the present invention, the interactive operation mode includes the following steps:

[0037] - Issue a selected action from a predetermined set of actions to the user, the selection of which is based on the session history log and action compliance value, wherein the selected action is issued via the visual attraction element and / or the interaction unit;

[0038] - The signal representing the local concentration of the narcotic substance from the respiratory measurement unit is sampled and the sampling results are analyzed. Based on the analysis results, it is determined whether the respiratory concentration of the narcotic substance of the user can be classified within the required level of accuracy and precision.

[0039] If classification is determined to be feasible at the desired level of accuracy and precision, then:

[0040] - Determine the respiratory concentration of the narcotic substance, and

[0041] - Compare the inhaled concentration of the narcotic substance with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; and

[0042] If the classification is determined to be impossible, then:

[0043] - Using input from at least one auxiliary sensing unit, a motion compliance value is determined based on an analysis of how well the user has complied with the selected action. The auxiliary sensing unit provides additional information about the user that differs from that of the respiratory measurement unit.

[0044] - Update the session history log, which includes information about which action from the predetermined action set has been issued;

[0045] - Repeat the steps in interactive mode until a constraint level is established or a predetermined maximum time period is reached.

[0046] According to one embodiment of the method, issuing a selected action includes the respiratory analysis system using one or a combination of the interaction units: a speaker; and a display.

[0047] According to one embodiment of the method, determining the action compliance value after the selected action is issued includes using one or a combination of the auxiliary sensing units: a camera combined with image analysis capabilities, a microphone combined with voice recognition capabilities, an IR sensor, and a seat occupancy sensor.

[0048] According to one aspect of the present invention, a method and a respiratory analysis system are provided. The respiratory analysis system includes a respiratory measurement unit, at least one visual attraction element, at least one auxiliary sensing unit, at least one interaction unit, and a CPU. The respiratory analysis system is configured to provide a compliance mode including the following steps:

[0049] - The signal representing the local concentration of the narcotic substance from the respiratory measurement unit is sampled, the sampling results are analyzed, and the results of the analysis are used to determine whether the respiratory concentration of the narcotic substance in the user can be classified within the required level of accuracy and precision.

[0050] -If the category is determined to be potentially executable, then:

[0051] Determine the respiratory concentration of the narcotic substance, and

[0052] The inhaled concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level, and if a classification is determined to be impossible to execute, an interactive operation mode is provided, the interactive operation mode comprising the following steps:

[0053] - Issue a selected action from a predetermined set of actions to the user, the selection of which is based on the session history log and action compliance value, wherein the selected action is issued via the visual attraction element and / or the interaction unit;

[0054] - The signal representing the local concentration of the narcotic substance from the respiratory measurement unit is sampled and the sampling results are analyzed. Based on the analysis results, it is determined whether the respiratory concentration of the narcotic substance of the user can be classified within the required level of accuracy and precision.

[0055] -If classification is determined to be feasible at the desired level of accuracy and precision, then:

[0056] Determine the respiratory concentration of the narcotic substance, and

[0057] The inhaled concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; and

[0058] If the classification is determined to be impossible, then:

[0059] - Using input from at least one auxiliary sensing unit, a motion compliance value is determined based on an analysis of how well the user has complied with the selected action. The auxiliary sensing unit provides additional information about the user that differs from that of the respiratory measurement unit.

[0060] - Update the session history log, which includes information about which action from the predetermined action set has been issued;

[0061] - Repeat the steps in interactive mode until a constraint level is established or a predetermined maximum time period is reached.

[0062] This invention provides a breath analysis method and system that significantly reduces time to a reliable classification in the vast majority of testing scenarios. In particular, for conscious users following given instructions, the test will be quick and convenient.

[0063] One advantage provided by this invention is that the system utilizes most of the equipment already available in vehicles, such as touchscreens, voice recognition systems, and various sensors / detectors.

[0064] Another advantage is that this method offers an extension of actions that can be provided to the user, such as giving the user a warning that is not necessarily above the legal limits for narcotic substances, but still draws attention. The warning can be given in a way that also notifies passengers in the vehicle.

[0065] A further advantage is that the complexity of the actions requested by the user increases progressively, and consequently, the time required to perform the actions and / or analyze the results also increases progressively. Thus, complex and time-consuming actions are only utilized when actually needed.

[0066] The invention will now be described in more detail by way of example and non-limiting embodiments thereof, with reference to the accompanying drawings. Attached Figure Description

[0067] Figure 1a This is a schematic diagram of a respiratory analysis device according to the present invention, and Figure 1b This is a schematic diagram of a system according to the invention implemented in the dashboard of a vehicle;

[0068] Figure 2 This is a flowchart of the method according to the present invention; and

[0069] Figure 3 It is a graph illustrating how the method and system according to the present invention provide analytical results about the time from the start of the process. Detailed Implementation

[0070] Terms such as “top,” “bottom,” “upper,” “lower,” “below,” “above,” etc., are used merely with reference to the geometry of embodiments of the invention shown in the accompanying drawings and / or during normal operation of one or more devices, and are not intended to limit the invention in any way.

[0071] In this context, classification refers to determining whether the subject's inhaled concentration of an stimulant substance (e.g., ethanol) is above or below a predefined threshold.

[0072] Tracers are physiological substances inherently associated with exhaled breath, such as carbon dioxide or water vapor.

[0073] The baseline refers to the signal level corresponding to the concentration of the narcotic or tracer; other instantaneous signal values ​​are referenced to this signal level. Offset error is the deviation from the baseline.

[0074] The concentration peak is defined by the change of the maximum value of the measured concentration relative to time, where the concentration increases before the peak value and decreases thereafter.

[0075] The following description of a breathalyzer system and method for determining and classifying the concentration of narcotic substances will primarily focus on a system installed in and integrated with a vehicle. This is a typical implementation. However, as those skilled in the art will recognize, the system and method can also be implemented in other ways, such as, but not limited to, stand-alone systems used at the entrance to a restricted work area, vehicle depot, etc. Modifications to such implementations will be apparent to those skilled in the art based on this description.

[0076] The respiratory analysis system and method according to the invention will be primarily described as a contactless detection system installed in a vehicle, representing a key implementation of the invention. As those skilled in the art will recognize, the teachings are equivalent to standalone systems (e.g., systems at the entrance to work areas, fleet depots, etc.). According to some embodiments described below, the system and method according to the invention can be a combination of a contactless detection system and an active system utilizing a mouthpiece for sampling respiratory samples.

[0077] The main concern for gaining public acceptance of widespread or even mandatory sobriety testing, for example, in vehicles, is the time required to perform the tests and / or whether the tests are inconvenient for drivers to perform. It should also be recognized that while intoxicated drivers are a significant problem, the majority of drivers are sober, and therefore, sobriety testing performed in vehicles can be expected to detect no illegal amounts of sedatives in the vast majority of test instances. Estimates made by the Swedish Transport Authority give that 99.8% of drivers have blood alcohol concentrations below the legal limit. Although the exact figures vary across different countries, it is typically far lower than the 1% of all tests expected to result in concentrations above the legal limit. Breathalyzer systems are considered to have a good chance of acceptance: they are quick and convenient for visibly sober users who comply with given instructions, but will be more time-consuming in cases where early instructions indicate the presence of sedatives and / or user obstruction. The idea of ​​providing a system that follows a compliance detection mode as the normal operating mode, quick and convenient for most users and / or most testing occasions, and can switch to an interactive detection mode when needed. Interactive testing mode can be considered a special operating mode that requires interaction with the user and more time-consuming measurement / analysis, and is used only for a small portion of all test instances.

[0078] Figure 1aThis is a schematic diagram of the functional units of a respiratory analysis system 100 according to the present invention, including a respiratory measurement unit 12. The respiratory measurement unit 12 includes a measuring instrument or chamber 12a into which a respiratory sample is drawn for analysis of its tracer and narcotic substance content. The respiratory measurement unit 12 further includes: an inlet 12b connected to one end of the measuring instrument 12a; and an outlet 12c connected to the other end. The respiratory measurement unit 12 is further typically provided with: a fan for driving airflow through the measuring instrument; and one or more heaters for heating the incoming air and controlling the temperature of the incoming air. The respiratory measurement unit 12 will provide an estimate of one or more narcotic substances associated with the user. The respiratory measurement unit 12 may be referred to as a main sensing unit because the output from the device is central for further analysis and represents a measure of what decisions to make. Other main sensing units may be present in the vehicle, for example, a biometric detector for verifying the user's identity. One or more visual attraction elements 13 may be provided near the inlet 12b of the respiratory measurement unit 12. A visual attraction element 13 is provided to attract the user's attention, causing him / her to turn towards the visual attraction element 13 and thus also towards the inlet 12c of the respiratory measurement unit 12. According to one embodiment, the visual attraction element is an LED arranged to illuminate during respiratory sampling. Alternatively, the visual attraction element 13 can be an indicator or illustration on an existing display, such as an arrow pointing in the direction of the inlet 12c, which is displayed on the existing display during respiratory sampling.

[0079] The respiratory analysis system 100 may further be provided with at least one auxiliary sensing unit 14. The auxiliary sensing unit 14 is arranged to provide additional information related to the user, distinct from that of the main sensing unit. Examples of the auxiliary sensing unit 14 include, but are not limited to, a camera 14a combined with image analysis capabilities, a microphone 14b combined with voice recognition capabilities, an IR sensor 14c, and a seat occupancy sensor (not shown). The auxiliary sensing unit 14 may be used individually or in combination to provide information related to how the user complies with instructions given by the respiratory analysis system, and also to provide other information useful in the analysis, such as the passenger's presence and location within the carriage.

[0080] The respiratory analysis system 100 is further provided with at least one interaction unit 15, which is used by the system to convey instructions to a user and may also be arranged to receive responses from the user. Examples of the interaction unit 15 include, but are not limited to, a speaker 15a, combined with a speech generation function; and a display 15b, which can display instructions as, for example, text messages, images, videos, and animations. The display 15b may also be a touchscreen that allows input from the user. Alternatively, other known types of input units may be provided, such as units for speech recognition.

[0081] Measurement unit 12, auxiliary sensing unit 14, and interaction unit 15 are connected to central processing unit (CPU) 11, which controls the connected devices and receives and processes input signals or data from the devices. The respiratory analysis system 100 may further include a wired or wireless communication unit 16 for communicating with external entities or other systems of the vehicle. A long-term memory, which can be connected to CPU 11, is provided to act as a digital library 17, storing various messages, images, or videos for CPU 11 to select from to provide different instructions to the user. Program memory 18 is typically included to store the system's operating sequence. As those skilled in the art will appreciate, means for storing data, parameters, and instructions can be provided in many different ways, and the use of digital library 17 in conjunction with program memory 18 should be considered a non-limiting example of a suitable memory configuration. Power supply unit 19 is provided to provide power to all units / devices of the system. Alternatively, the units / devices of the system may be powered by the vehicle's public power supply system.

[0082] As those skilled in the art will recognize, many of the units and devices described in the Breath Analysis System 100 are already present in the infotainment systems of modern vehicles. Examples include speakers in the audio system, microphone(s), devices for speech recognition / generation, and various displays. Therefore, an obvious design choice is to “reuse” as much existing equipment as possible, rather than to replicate certain devices. According to one embodiment, the Breath Analysis System 100 is integrated with the vehicle's infotainment system, and at least the CPU, power supply, and audio system are portions used by both the infotainment system and the Breath Analysis System 100. Some of the units described above are not necessarily discrete units; for example, the speech recognition unit is typically a function or application running in the CPU or another processing unit. Those skilled in the art will recognize that the units and functions described above can be implemented in different ways, and the choice between dedicated hardware or multi-purpose hardware with different functions provided by software or firmware will be made in accordance with the teachings of the invention and the limitations and possibilities offered by particular implementations. Therefore, the design of a system, such as a standalone Breath Analysis System, which provides all the above functions “alone,” can be quite different from that of a vehicle-installed system with a large number of audiovisual communication facilities already present in a vehicle.

[0083] exist Figure 1b An exemplary implementation of the respiratory analysis system according to the present invention is schematically illustrated. Figure 1bThe instrument panel 20 of a vehicle (e.g., an automobile) is shown. The system is positioned and integrated with the instrument panel 20 and the steering wheel 21. The inlet 12b of the breathing measurement unit 12 is provided close to the center of the steering wheel 21, and very close to the inlet 12b is a light source positioned as a visual attraction element 13. The auxiliary sensing unit 14 is provided on the instrument panel 20 in the form of a camera 14a and a microphone 14b, and is adapted to monitor signals related to driver behavior. An interaction unit 15, including a speaker 15a and a display 15b (e.g., a touchscreen), is also provided on the instrument panel 20.

[0084] exist Figure 2 The flowchart illustrates a method according to the present invention for determining a constraint level for a user performing a specified task (typically, a driver who will start and drive a vehicle). Reference Figure 1a The described respiratory analysis system 100 is arranged to perform the steps of the method. The method includes two different operating modes: a compliance mode and an interactive mode. The compliance mode is designed to be rapid and does not require any specific actions from the driver beyond what is typically required while sitting in a driver's seat and breathing normally; this represents the basic instructions that all drivers should already be aware of. If the driver is awake and complies with these basic instructions, respiratory analysis can be performed in less than 10 seconds, preferably within 5 seconds. Therefore, for most testing scenarios, the method of the present invention should be in compliance mode, as discussed above. Interactive mode will only be entered when necessary (i.e., if respiratory analysis cannot be performed correctly in compliance mode). The reasons are, for example:

[0085] The concentration of the narcotic substance in the exhaled breath appeared to be close to the permissible limit, but the estimated uncertainty in the measurement was too great to definitively classify the driver.

[0086] - Breath analysis could not be performed due to driver obstruction.

[0087] - Breathing analysis could not be performed due to equipment malfunction.

[0088] - Breath analysis cannot be performed due to disturbances in the carriage (e.g., passengers with breath containing alcohol, windows open on windy days, and the presence of substances that may interfere with breath analysis).

[0089] - Any ambiguity in the available data, which may include both respiratory analysis data and input from the auxiliary sensing unit 14.

[0090] Interactive modes can take significantly longer than conforming modes. However, part of the method according to the invention is to progressively increase the likelihood of requests for interactive responses from the user, and therefore, the time required to perform classification also progressively increases. For example, the first failure to perform classification might typically result in a relatively quick action being issued to the user as the first attempt.

[0091] One part of the interactive operating mode is establishing action compliance values, which must exceed minimum requirements to classify the user's driving ability in terms of constraint levels. The session history log, including data recorded during the session, is used as a tool to determine updated versions of the action compliance values. The session history log includes information related to the selected actions issued in the current interactive mode session and the corresponding results of those actions; the action compliance value is a value determined based on the result of the issued selected action.

[0092] At the start of the interactive operation mode, the action compliance value is quantified to be below a required threshold to allow classification into the constraint level. The action compliance value is updated based on more detailed instructions and requests, and more data is obtained. The calculated, updated action compliance value determines the user's driving ability with respect to the applicable constraint level. The contents of the session history log are obtained using data recorded from sensor signals during the session through which the action compliance value is calculated.

[0093] The method according to the invention utilizes two sets of parameters and / or instructions, the contents of which have been previously provided and stored:

[0094] - A set of constraint levels, including "unrestrained driving," "driving with issued warnings," "limited drivability," and "ignition lock-up." A constraint level can be selected based on the measured respiratory concentration of the narcotic substance in the user, where a first concentration range corresponds to a first constraint level, a second concentration range corresponds to a second constraint level, and so on. The concentration range can correspond to the legal levels of one or more narcotic substances, and physiological aspects, such as whether the subject is in the absorption or elimination phase of the substance's concentration kinetics, can also be considered. Furthermore, in interactive mode, non-compliance with issued instructions may affect the selection of constraint levels, such that a constraint level limiting drivability is selected even if classification cannot be performed. Moreover, if the respiratory concentration of the narcotic substance is measured to be within, for example, a first range, a higher constraint level can be selected if non-compliance is determined (e.g., based on input from the auxiliary sensing unit 14).

[0095] - A predefined set of actions, such as including actions:

[0096] -Activate visually appealing elements

[0097] - Issue the instruction: "Facing the detector"; "Lean forward, exhale towards inlet 12b, facing the detector."

[0098] - Issue a warning: "Data is still missing. If not corrected, driving will be restricted or stopped."

[0099] The content can vary depending on the current implementation of the system and method, adapting to changes in aspects such as the availability of the auxiliary sensing unit 14 and / or the type of the interaction unit 15. Thus, the method according to the invention can be adapted to different hardware configurations by typically only requiring updates to the content of the set. Furthermore, how the actions will be implemented in detail will depend on the hardware configuration and the equipment in the vehicle. For example, ignition locking can be provided as an existing function of separation in the vehicle, but if not, an equivalent locking effect can be provided by other means.

[0100] The operating mode of the method according to the present invention includes the following steps: 200: sampling a signal representing the local concentration of the narcotic substance, analyzing the sampling results, and determining, based on the analysis results, whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision; 205: if classification is determined to be impossible to perform, then:

[0101] 205:1: Determine the respiratory concentration of the narcotic substance, and

[0102] 205:2: Compare the respiratory concentration of the narcotic substance with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, where each predetermined concentration interval corresponds to a predetermined constraint level;

[0103] 210: If the classification is determined to be impossible to execute, the method enters the interactive operation mode.

[0104] The interactive operation mode includes the following steps: 215: Issue a selected action to the user from a predefined set of actions, the selection of which is based on the session history log and action compliance value;

[0105] 220: Sample the signal representing the local concentration of the narcotic substance, analyze the sampling results, and determine, based on the analysis, whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision; 225: If classification is determined to be possible, then:

[0106] 225:1: Determine the respiratory concentration of the narcotic substance, and

[0107] 225:2: Compare the respiratory concentration of the narcotic substance with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, where each predetermined concentration interval corresponds to a predetermined constraint level; and

[0108] If the classification is determined to be impossible, then:

[0109] 230: Determine the action compliance value based on analysis of how well the user has already complied with the selected action issued;

[0110] 235: Update the session history log, which includes information on which action from the predefined action set has been issued; 240: Repeat steps (215-235) in interactive mode until a constraint level is established or a predefined maximum time period is reached.

[0111] Determining whether classification is possible (steps 205 and 225) should be interpreted as the ability to measure the concentration of the stimulant substance in the user's exhaled breath with acceptable accuracy and precision, and to classify whether the concentration is above or below a predetermined level (typically, a legal level) or within a predetermined range. Acceptable accuracy / precision can typically and preferably be determined by statistical analysis of the sampled data, typically in conjunction with knowledge of known error levels and predictable fluctuations (e.g., temperature dependence) in the breath analysis system. Due to the importance of correct classification, it is crucial that the entire measurement process be performed in a manner that ensures a high degree of determinism in the measurement of concentration. It is also feasible to include a "safety margin" in the use of the measured results to determine constraint levels, for example, to take into account the fact that a determination of a concentration at a certain point in time may be invalid after a certain time, depending on whether the subject is in the absorption or elimination phase of the substance's concentration kinetics. This aspect is particularly important in cases with low legal limits (e.g., in Sweden). The typical duration of the absorption phase is 30 minutes across a wide range of alcohol concentrations. Typically, elimination is linear over time, but can vary considerably from one individual to another. Typically, one centiliter of pure alcohol is metabolized in one hour.

[0112] Given the predetermined levels of accuracy and precision required, those skilled in the art can implement suitable measurement systems and methods. Co-pending application SE 2050105-2 by the same applicant as this invention provides a particularly time-efficient system and method for performing accurate and precise measurements and classifications.

[0113] According to one embodiment, the sedative substance is alcohol, and the measurement performed by the breath analysis system is a BrAC measurement (BrAC—breath alcohol concentration). A preferred method is a system based on tracer gas measurement, as described, for example, in US7919754 and US9746454.

[0114] According to one embodiment, the constraint level set includes multiple actions or settings representing increased restrictions on the drivability of the vehicle. The constraint level set may include: issuing a warning to the user, setting the vehicle to a limited drivability mode, and ignition lock. A constraint level should typically represent completely unrestricted use of the vehicle when the method has entered an interactive operating mode, and further steps result in: the user complying with given instructions, and any concentration of the narcotic substance being below a minimum legal limit. According to one embodiment, the constraint level set includes: unrestricted use of the vehicle and at least one of: issuing a warning to the user, setting the vehicle to a limited drivability mode, and ignition lock. Depending on the nature of the constraint level determined by the method and the respiratory analysis system 100, the results may be transmitted to other systems / functions of the vehicle, such as ignition lock. The results may also be transmitted to external entities, such as a fleet management system.

[0115] According to one embodiment, the predetermined set of actions includes multiple actions that can be grouped according to the following:

[0116] Pay attention to actions, such as activating visually appealing element 13.

[0117] - Command actions, for example, using the interaction unit 15 to issue the command "Please face the detector".

[0118] - Requests for actions, such as urging the driver to lean forward towards inlet 12b, can be combined with messages stating that if the user does not comply, there may be subsequent restrictions on driving ability.

[0119] - Warning actions, for example, using the interaction unit 15 to issue a warning "Your driving ability has not been verified due to missing data".

[0120] According to one embodiment, determining a motion compliance value includes evaluating sampling results, wherein improved classification support results in an increased motion compliance value, even if the sampling results are still insufficient for a final classification. Determining a motion compliance value may include evaluating auxiliary input data. Auxiliary input data typically includes data received from one or more of the auxiliary sensing units 14. Auxiliary input data may include video or images, signals from IR sensors (for detecting the presence of a user or passenger), and seat occupancy sensors. User behavior is analyzed and classified based on video and / or image analysis or other signals, or based on a combination thereof. The analysis can range from establishing the presence of a user to identifying the presence of multiple people in and around the vehicle using advanced image processing.

[0121] According to one embodiment, a further step is introduced to be taken upon the issuance of a selected action (typically, a warning action). This further step includes: the user confirming that he / she has understood the warning, and the system receiving and preferably storing such confirmation. Similarly, the user can be asked to confirm acceptance of a constraint in a step to be taken after a constraint has been issued. The confirmation can be input to the system via interaction unit 15.

[0122] According to one embodiment, the action compliance value determined in step 230 is based on the analysis of whether the measurement of the narcotic substance has improved the likelihood of classification to a predetermined level of certainty.

[0123] According to one embodiment, the interactive operating mode includes utilizing at least one auxiliary sensing unit 14. The auxiliary sensing unit 14 provides user compliance input used in step 230 of determining a motion compliance value. The motion compliance value can be based on both further user compliance input and changes (intended improvements) in the measurement results of the stimulant substance. The user compliance input provided by the auxiliary sensing unit 14 can be, for example, an image provided by a camera 14a combined with an image analysis function, which is considered to indicate whether the user has followed, for example, an instruction to face the detector. The motion compliance value is preferably parameterized as a set of integer values. One example is having three values, where value 1 corresponds to the user not following the instruction for the selected action, value 2 corresponds to partially following the instruction, and value 3 corresponds to fully following the instruction. The values ​​can be determined based on image or video analysis, where, for example, when the instruction is “lean forward toward the inlet,” value 1 is the user deliberately moving away from the sensor to guide his / her breathing, value 2 is guiding breathing toward the inlet, and value 3 is the user actually leaning close to the inlet. Such image / video analysis can be implemented by those skilled in the art in the context of existing methods. The analysis is not limited to the use of only one auxiliary sensing unit 14. For example, advantageously, inputs from a camera 14a combined with image analysis capabilities, a microphone 14b combined with voice recognition capabilities, an IR sensor 14c, and a seat occupancy sensor, in various combinations, can be used to analyze user behavior and provide action compliance values ​​after an action has been issued. It should also be understood that, typically, the action compliance value depends on the issued instruction and also on the session history log.

[0124] The session history log includes a list of selected actions and corresponding action compliance values, and can typically be stored in program memory 18. According to one embodiment, the session history log is refreshed for each session, such as a driving session or an entry into a restricted area. According to one embodiment, the historical session log is maintained for a predetermined period of time, such as approximately 30 minutes. This is to prevent the user from aborting the vehicle's start-up process in an attempt to manipulate the system. This functionality is preferably combined with a user identification mechanism so that the historical session log is reset if the user changes. When the identity of the subject is known from any of the available data sources, the compliance value can be personalized by comparing the actual compliance with the normal behavior of that particular subject, as can be seen from previous session history logs.

[0125] According to one embodiment of the invention, at least one auxiliary sensing unit 14 is activated in compliance mode, and if information obtainable from the auxiliary sensing unit 14 indicates tampering with the respiratory analysis, compliance mode is terminated and the method proceeds directly to interactive mode.

[0126] According to an embodiment of the present invention, using a reference Figure 1a and 1b The described respiratory analysis system 100, in an interactive operation mode, includes the following steps: 215': issuing a selected action from a predetermined set of actions to the user, the selection of the action being based on the session history log and the action compliance value, wherein the selected action is issued via the visual attraction element 13 and / or the interaction unit 15.

[0127] 220': Sample the signal representing the local concentration of the sedative substance from the respiratory measurement unit 12, analyze the sampling results, and determine whether the user's respiratory concentration of the sedative substance can be classified within the required level of accuracy and precision based on the analyzed results;

[0128] 225': If classification is determined to be feasible at the desired level of accuracy and precision, then:

[0129] 225:1': Determine the respiratory concentration of the narcotic substance, and

[0130] 225:2': Compare the respiratory concentration of the narcotic substance with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, where each predetermined concentration interval corresponds to a predetermined constraint level; and

[0131] If the classification is determined to be impossible, then:

[0132] 230': Using analysis from at least one auxiliary sensing unit 14, a motion compliance value is determined based on how well the user has complied with the selected action. The auxiliary sensing unit provides additional information related to the user that is different from that of the breathing measurement unit 12.

[0133] 235': Update the session history log, which includes information about which action from the predefined action set has been issued;

[0134] 240: Repeat the steps (215-235) of the interactive mode until a constraint level is established or a predetermined maximum time period is reached.

[0135] According to one embodiment, the selected action issued in step 215' includes one or a combination of the following using the interaction units 15 of the respiratory analysis system 100: a speaker 15a, typically and preferably combined with a voice generation function; and a display 15b, which can display instructions as, for example, text messages, images, videos, and animations. The display 15b may also be a touchscreen that allows input from the user.

[0136] According to one embodiment, the action compliance value determined in step 230' for issuing the selected action includes one or a combination of the auxiliary sensing units 14: camera 14a, combined with image analysis function; microphone 14b, combined with voice recognition function; IR sensor 14c; and seat occupancy sensor.

[0137] According to one embodiment of the present invention, the step of selecting a constraint level from a predetermined set of constraint levels (step 205:2 / 225:2 / 225:2') further includes: using one or a combination of interaction units 15 to notify the user of the constraint level.

[0138] The use of the system and method according to the invention can be explained from a time-consumption perspective. The compliance detection mode should be completed within 5 seconds. The decision-making process in the interactive detection mode based on respiratory analysis sensor data and the driver's response / compliance can include the following four main stages (and their time windows from start to finish):

[0139] • Note (0-5 seconds)

[0140] • Instructions (5-10 seconds)

[0141] • Request for action (10-20 seconds)

[0142] • Warning (20-30 seconds).

[0143] exist Figure 3The diagram illustrates the levels and timings for the four main stages. Experienced, alert drivers are typically approved within 3-5 seconds and permitted to drive without restraints. If data is lost, the driver receives detailed instructions on how to provide an approved breath sample before the vehicle's drivability is enabled. If data for the breath analysis is still lost after 10 seconds, a request for action is issued with repeated and more detailed instructions. If data is still lost after 20 seconds, a warning is issued. In this scenario, a final drivability decision and restraint level are issued after 30 seconds.

[0144] The embodiments described above should be understood as illustrative examples of the systems and methods of the present invention. Those skilled in the art will understand that various modifications, combinations, and changes can be made to the embodiments. In particular, where technically possible, different portions of the solutions in different embodiments can be combined in other configurations.

Claims

1. A method for operating a respiratory analysis system (100) to determine a constraint level for a user based on an analysis of the concentration of narcotic substances in the exhaled breath of a user performing a specified task and the user's behavior, the method comprising a compliance operating mode and an interactive operating mode, the method utilizing a predetermined set of constraint levels and a predetermined set of actions, The compliance operation mode includes the following steps: - Sample the signal representing the local concentration of the narcotic substance, analyze the sampling results, and determine, based on the analysis results, whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision; - If the category is determined to be potentially executable, then: - Determine the respiratory concentration of the narcotic substance, and - The respiratory concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; - If the classification is determined to be impossible to execute, the method enters the interactive operation mode, which includes the following steps: - Issue a selected action from a predetermined set of actions to the user. The selection of the instruction is based on the session history log and the action compliance value, wherein the session history log includes information related to the selected action issued in the current interactive mode session and the corresponding result of the issued selected action, and the action compliance value is a value determined based on the result of the issued selected action. - The signal representing the local concentration of the narcotic substance is sampled and the sampling results are analyzed, and the results are used to determine whether the user's respiratory concentration of the narcotic substance can be classified within the required level of accuracy and precision. - If classification is determined to be possible, then: - Determine the respiratory concentration of the narcotic substance, and - The respiratory concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; as well as If the classification is determined to be impossible, then: - Determine the action compliance value based on an analysis of how well the user has complied with the selected action issued; - Update the session history log, which includes at least information about which action from the predetermined action set has been issued; - Repeat the steps of the interactive operation mode until the constraint level is established.

2. The method of claim 1, wherein the set of constraint levels includes a plurality of constraint levels representing an increase in the drivability of the vehicle.

3. The method of claim 2, wherein the set of constraint levels includes one or more of the constraint levels corresponding to the settings of the vehicle: unconstrained driving, driving with issued warnings, limited drivability, and ignition lock.

4. The method of claim 1, wherein the predetermined set of actions includes at least one subset of: attention actions, instruction actions, requests for actions, and warning actions.

5. The method of claim 4, wherein the attention action includes activating a visually attractive element (13).

6. The method of claim 4, wherein the interaction unit (15) is used by the respiratory analysis system (100) to transmit actions to the user.

7. The method according to any one of claims 1 to 6, further comprising a step to be taken when the selected action is issued, the further step comprising receiving confirmation from the user of understanding and acceptance of the selected action.

8. The method according to any one of claims 1 to 6, wherein the determined action compliance value is based on an analysis of the possibility that the measurement of the narcotic substance has improved the classification to the desired level of accuracy and precision.

9. The method according to any one of claims 1 to 6, wherein the determined action compliance value is based at least in part on the input provided by the auxiliary sensing unit (14).

10. The method according to claim 1, wherein the interactive operation mode comprises the following steps: - Issue a selected action from a predetermined set of actions to the user, the selection of which is based on the session history log and action compliance value, wherein the selected action is issued via a visual attraction element (13) and / or an interaction unit (15); - The signal representing the local concentration of the sedative substance from the respiratory measurement unit (12) is sampled, the sampling results are analyzed, and the results of the analysis are used to determine whether the respiratory concentration of the sedative substance of the user can be classified within the required level of accuracy and precision. - If classification is determined to be feasible within the desired levels of accuracy and precision, then: - Determine the respiratory concentration of the narcotic substance, and - The respiratory concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level; as well as If the classification is determined to be impossible, then: - Using input from at least one auxiliary sensing unit (14), an action compliance value is determined based on an analysis of how well the user has complied with the selected action given, the auxiliary sensing unit provides additional information about the user that is different from that of the breathing measurement unit (12); - Update the session history log, which includes information about which action from the predetermined action set has been issued; - Repeat the steps of the interactive operation mode until the constraint level is established.

11. The method of claim 10, wherein the step of issuing the selected action includes the respiratory analysis system (100) using one or a combination of the interaction units (15): a speaker (15a); and a display (15b).

12. The method of claim 10, wherein determining the action compliance value after the selected action is issued includes using one or a combination of the auxiliary sensing units (14): a camera (14a) combined with image analysis functionality, a microphone (14b) combined with voice recognition functionality, an IR sensor (14c), and a seat occupancy sensor.

13. The method according to any one of claims 1 to 6, wherein if a predetermined maximum time period is reached, the repetition of the step of interactive operation mode is terminated.

14. A respiratory analysis system (100) comprising a respiratory measurement unit (12), at least one visual attraction element (13), at least one auxiliary sensing unit (14), at least one interaction unit (15), and a CPU (11), wherein the respiratory analysis system (100) is configured to provide a compliant operating mode comprising the following steps: - The signal representing the local concentration of the sedative substance from the respiratory measurement unit (12) is sampled, the sampling results are analyzed, and the results of the analysis are used to determine whether the respiratory concentration of the user's sedative substance can be classified within the required level of accuracy and precision. - If the category is determined to be potentially executable, then: Determine the respiratory concentration of the narcotic substance, and The inhaled concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level, and if a classification is determined to be impossible to execute, an interactive operation mode is provided, the interactive operation mode comprising the following steps: - Issue a selected action from a predetermined set of actions to the user, the selection of which is based on the session history log and action compliance value, wherein the selected action is issued via the visual attraction element (13) and / or the interaction unit (15); - The signal representing the local concentration of the sedative substance from the respiratory measurement unit (12) is sampled, the sampling results are analyzed, and the results of the analysis are used to determine whether the respiratory concentration of the sedative substance of the user can be classified within the required level of accuracy and precision. - If classification is determined to be feasible within the desired levels of accuracy and precision, then: Determine the respiratory concentration of the narcotic substance, and The inhaled concentration of the narcotic substance is compared with a set of predetermined concentration intervals to select a constraint level from a set of predetermined constraint levels, wherein each predetermined concentration interval corresponds to a predetermined constraint level. as well as If the classification is determined to be impossible, then: - Using input from at least one auxiliary sensing unit (14), an action compliance value is determined based on an analysis of how well the user has complied with the selected action given, the auxiliary sensing unit provides additional information about the user that is different from that of the breathing measurement unit (12); - Update the session history log, which includes information about which action from the predetermined action set has been issued; - Repeat the steps of the interactive operation mode until the constraint level is established.

15. The respiratory analysis system (100) according to claim 14, wherein the auxiliary sensing unit (14) is one or a combination of the following: a camera (14a), a microphone (14b), an IR sensor (14c), and a seat occupancy sensor.

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