Avalanche probe for snow cover analysis

Abstract

The invention relates to an avalanche probe for snow cover analysis, comprising a plurality of elongate probe elements (1) which can be releasably connected to one another via a plug-in connection in order to form a substantially rod-shaped arrangement of the length L, wherein the probe elements (1) each have an outer, substantially tubular casing (110), wherein at least individual probe elements (1) each have at least one temperature sensor (101), preferably three temperature sensors (101), and the avalanche probe has at least two temperature sensors (101) which are arranged at a distance D along the length L when the probe elements (1) are arranged in a connected manner, wherein the avalanche probe is characterized in that the temperature sensors (101) are arranged within the casing (110) of the respective probe element (1), and the casing (110) has a recess (111) for each temperature sensor (101), wherein the respective temperature sensor (101) is arranged in a flush manner in the recess (111).

Description

[0001] AVALANCHE PROBE FOR SNOW BLANKET ANALYSIS The present invention relates to a probe for analyzing the temperature profile in a snow blanket, a method for determining temperature data and a computer-implemented method for estimating avalanche risk.

[0002] BACKGROUND OF THE INVENTION

[0003] Due to the increase in winter sports activities and the growth of mountain tourism, the risk of avalanche accidents in mountain regions is steadily increasing.

[0004] Safety equipment for ski tourers, freeriders, and mountain rescuers includes avalanche transceivers, avalanche shovels, and avalanche probes. In an emergency, using an avalanche probe allows for a significantly faster rescue. It serves to precisely determine the position and depth of an avalanche victim in the snow and must therefore be long and sturdy enough to penetrate deep into the snowpack. On the other hand, the equipment's volume and weight are advantageously limited. An avalanche probe therefore consists of several connectable sections, usually made of lightweight materials such as aluminum, titanium, or carbon. When assembled, it is typically between 2 and 4 meters long and weighs approximately 200-250 grams.

[0005] Besides the necessary equipment for an avalanche, the assessment of avalanche danger, for example by avalanche warning services, plays a very important role. Due to small-scale influencing factors, a regional assessment of the avalanche situation can often be inaccurate.

[0006] To detect avalanche danger early and make appropriate risk assessments for activities, a precise analysis of snowpacks is essential, in addition to considering topographical influences and actual avalanche events. A superficial analysis of the snowpack is insufficient, as the layered structure of the snowpack can be crucial for the assessment. This assessment considers various parameters such as temperature, acoustic emission, moisture, density, and stability of the snowpack.In connection with the recording of local temperature gradients in snow for research purposes, a so-called "Snow Temperature Profile Probe" (STPP) with a length of 2.3 m and temperature-sensing semiconductor chips spaced 10 cm apart was developed as part of a master's thesis (Deems, JS, 2002, Topography effects on the spatial and temporal patterns of snow temperature gradients in a mountain snowpack, available at sites.wamercnr.colosate.edu / wp-content / uploads / sites / 74 / 2017 / 09 / MSU_EarthSci_MS_thesis_Jeffrey_Deems.pdf).

[0007] Various systems for monitoring snow or snowpack stability and avalanche activity are described in the prior art. US 5,661,464 A discloses a stationary probe for monitoring snowpack stability and avalanche activity. The device described in EP 3 935 359 Bl for measuring vertical temperature profiles with a housing designed as a floating system has also been proposed for analyzing a snowpack or ice layer.

[0008] CH 711 741 Al shows a device for determining avalanche danger based on the differential measurement of the position of the snow layers using vertical chains of tilt sensors.

[0009] A device for monitoring snow temperature and snowpack thickness in avalanche-prone areas is shown, among other places, in RU 2617 146 CI. The device is designed to be deployed by helicopter or skier and comprises several temperature sensors mounted vertically inside a rigid, rod-shaped plastic housing that extends along its entire length. The device also includes an antenna, a GPS receiver, a compass, position sensors, a radio modem, a control unit, a power supply, and a sharp point at the bottom of the tube. The control unit reads the measurements from the temperature sensors, GPS receiver, compass, and electronic gyroscope, records them in its internal memory, and transmits them via the radio modem to a remote server database for operational analysis. Power is supplied by an independent source.The software on the remote computer uses information about the temperature profile along the sensor to determine the position of the upper edge of the snowpack relative to the sensor. The position of the upper edge of the snowpack is determined, for example, by exceeding a predetermined threshold of the difference in measured values ​​between two adjacent temperature sensors, starting from the upper sensor. Such a device is designed to be stationary and to operate autonomously for a certain period of time.

[0010] A device for stationary measurement of snow layer thickness using temperature sensors is also disclosed in US 4,600,842 A.

[0011] DE 102016 104270 Al relates to a technique for determining snow profiles. The temperature of the snow layer in the measurement environment can be recorded as a thermal measurement. From this, the enthalpy and the state of matter of the snow layer can be determined. The device for recording a thermal measurement can include a temperature sensor designed to record the temperature of the snowpack in the specified measurement environment.

[0012] W003 / 056302 A1 discloses probes for measuring the density and strength properties of soil or snow. The sensor unit can include a temperature sensor in addition to sensors for penetration resistance. For determining snow stability, the vertical temperature profile of the snow is an important indicator of the probability of future metamorphism of the snow layers and the likelihood of an avalanche. This probe measures temperature data during insertion, among other things, and therefore it is not possible to obtain a rapid, standardized, and representative temperature profile across the entire depth of the snowpack.

[0013] DE 195 03 017 A1 discloses a device for measuring the layer structure of a snowpack (snow profile probe) using a temperature sensor, wherein the individual layer hardnesses of the respective snow layer thicknesses as well as the layer temperatures as a function of the snow depth along the probe can be recorded, evaluated and displayed as a snow profile. The document proposes that the snow profile probe can also be used as an avalanche probe.

[0014] In US 6,957,593 Bl and US 2014 / 116127 Al, portable devices for recording snow stability data are outlined.

[0015] The concept of an avalanche probe for snowpack analysis with multiple temperature measuring rings has already been (publicly) described by the inventors. However, an initial prototype did not meet the stability requirements to be suitable for practical use as an avalanche probe, and / or did not allow the acquisition of temperature data necessary for avalanche assessment.

[0016] BRIEF DESCRIPTION OF THE INVENTION

[0017] The object of the present invention is therefore to provide a device that is suitable as part of a mountaineer's safety equipment for use in open terrain and at the same time contributes to improving the assessment of the local avalanche danger.

[0018] This task is solved by an avalanche probe for snowpack analysis, comprising a plurality of elongated probe elements which can be detachably connected to each other via a plug connection in order to form an essentially rod-shaped arrangement of length L.

[0019] • wherein the probe elements each have an outer, essentially tubular shell,

[0020] • wherein at least individual probe elements each have at least one temperature sensor, and

[0021] • the avalanche probe has at least two temperature sensors which, when the probe elements are connected, are arranged at a distance D along the length L,

[0022] wherein the avalanche probe is characterized in that the temperature sensors are arranged within the casing of the respective probe element, and the casing has a recess for each temperature sensor, wherein the respective temperature sensor is arranged in the line of the recess.

[0023] The probe elements are typically connected by their casings, which are essentially straight tubes. If one end of the casing of a first probe element has an outer diameter smaller than the inner diameter of one end of the casing of a second probe element, the two probe elements can be connected. This connection allows the size of the avalanche probe to be adjusted. In one state, the probe elements are connected via the plug-in connection (plug-in state of length L), enabling the measurement of the temperature profile of a snowpack. In another state, the probe elements are not connected (unconnected state) and can, for example, be stored parallel to each other.This feature ensures the modularity of the avalanche probe and facilitates easy transport. As a result, the avalanche probe, when connected, can have a length L of 150 cm to 500 cm, advantageously 200 cm to 400 cm, while the individual probe elements, and thus the avalanche probe as a whole, when disconnected, can have a length 1 of 20 cm to 60 cm, advantageously 35 cm to 50 cm.

[0024] The placement of the temperature sensor within the probe allows the outer, essentially tubular casing (also called the shell) to retain its structural integrity. The typically point-like openings in the casing enable accurate measurement of the snowpack temperature without compromising the stability of the probe elements, allowing the avalanche probe to be inserted even into a compact snowpack. These openings can, for example, be holes with a diameter substantially smaller than the outer diameter of the tubular casing.

[0025] A multitude of temperature sensors can be arranged along the length of the probe, enabling the recording of a temperature profile over the entire length L. The term "temperature profile," as used herein, describes temperature values ​​along the entire length of the probe element or the snowpack. This temperature profile is determined during the use of an avalanche probe according to the invention. The temperature measurement, which will be discussed in detail with regard to the inventive method for acquiring temperature data, also allows for the recording of multiple measurements over time. Additional information can be derived from such a temperature gradient, such as whether the temperature sensor is located inside or outside the snowpack. The term "temperature gradient" is chosen in this context to express the change in ambient temperature over a time interval.The temperature gradient of a temperature sensor measuring the temperature of a snowpack shows an approximation of a stable temperature threshold. In contrast, the temperature gradient of a temperature sensor measuring the ambient temperature, or one positioned above the snowpack during the measurement process, exhibits different behavior, as the temperature is distorted, for example, by solar radiation. The temperature gradient thus makes it possible (automatically) to identify which temperature sensors are located outside the snowpack and should not be considered when determining the temperature profile within the snowpack. Therefore, the avalanche probe according to the invention, as defined above, can provide the necessary data for an avalanche risk assessment.

[0026] In a preferred embodiment, the avalanche probe according to the invention further comprises a head part which has a control unit and a housing, preferably designed as a handle.

[0027] The control unit, for example in the form of a microcontroller, centrally controls the temperature measurement and optionally the processing of the temperature data, either directly or by transmitting it to an external device such as a smartphone. To perform these functions, the central control unit can be connected to the temperature sensors of the probe elements.

[0028] Furthermore, the headpiece can include, for example, a charging socket, a battery, a switch, and several electronic components for the switch's circuit. Preferably, the headpiece is designed as a handle directly attached to a probe element, which, in the rod-shaped arrangement (assembled avalanche probe), constitutes the uppermost probe element. The housing of the headpiece can be made of a plastic, preferably polylactic acid (PLA) or glycol-modified polyethylene terephthalate (PETG). Advantageously, the housing of the headpiece is made of an injection-moldable and lightweight plastic, so that manufacturing by injection molding is possible.

[0029] In another preferred embodiment, the plug connections are each configured to form a detachable electrical contact that enables the transmission of data.

[0030] These types of connectors enable a connection between probe elements, and potentially between probe elements and a separate probe head, thus allowing data transmission and, advantageously, also power supply between the elements. The wireless nature of the connection minimizes stress on the material when connecting and disconnecting the avalanche probe elements and simplifies transport. This modularity also facilitates maintenance, repair, and replacement of individual probe elements. Consequently, the lifespan of the avalanche probe is extended, which can lead to reduced long-term costs.

[0031] Furthermore, it is preferred that the avalanche probe has a connecting cable with two ends, wherein a first end is fixedly connected to a probe element, runs slidably within further probe elements inside the casing / shell, and whose second end can be tensioned with a tensioning device such that all probe elements are held connected to one another. The tensioning device can preferably be arranged in the head section.

[0032] Such a construction with a connecting or guide rope, for example made of wire, is known for classic avalanche probes and allows the probe elements to be quickly brought together by throwing them out and pulling / tensioning the rope, in order to obtain the assembled avalanche probe as an essentially rod-shaped arrangement of length L.

[0033] Typically, the probe element, which is located at the end of the avalanche probe furthest from the head when the probe elements are connected, has a penetration tip. This preferably reinforced penetration tip facilitates penetration into the snow profile. In a preferred embodiment, the probe element with the penetration tip has a temperature sensor located at the tip. This temperature sensor allows the ground temperature to be recorded in addition to the temperature data of the snow profile.

[0034] In order to ensure that the proven handling is not significantly more complicated for the avalanche probe according to the invention, the features explained below with regard to the plug connection, via which the probe elements can be connected to each other, are preferred.

[0035] The plug connections are preferably configured such that the electrical contact is formed independently of the relative direction of rotation between the probe elements.

[0036] If the electrical contact is established by the plug connection independently of the relative direction of rotation between probe elements, the proven assembly of the avalanche probe via the connecting cable can be used to enable electrical contact and thus data transmission between the probe elements and the control unit, without the need for manual readjustment of the individual plug connections between the probe elements to orient the contact correctly. Suitable plug connections and contact elements, where the rotation at which the contacts meet is irrelevant, have been designed by the inventors and are described in more detail below and in the embodiments of Example 1.

[0037] In a preferred embodiment, the probe elements have a contact element at least at one end, preferably at both ends, selected from a female contact element or a male contact element.

[0038] It is understood that male and female contact elements complement each other to form a detachable electrical contact, enabling data transmission and power supply. In principle, probe elements with a female contact element at one end and a male contact element at the other can be combined to any desired length. The probe element with the head section and the probe element that forms the tip of the avalanche probe when assembled both typically have only one end with a contact element for establishing an electrical connection.

[0039] In a preferred embodiment, the male contact element comprises at least one, preferably two or three, spring contact pin(s), such as a test pin, a probe tip, a spring-loaded contact, a probe pin or a pogo pin.

[0040] Spring contact pins have a longitudinal axis that can be arranged parallel to or perpendicular to the longitudinal axis of the probe element. Typically, at least two spring contact pins are required for the application according to the invention to enable data transmission and also to supply power to the probe elements.

[0041] In a particularly preferred embodiment, the probe element, at one end which has a male contact element (for example, with at least one spring-loaded contact pin), comprises a male part of the mechanical connector, i.e., a section of the probe element's casing which, due to its smaller outer diameter, is suitable for insertion into the end of a casing of another probe element. In this embodiment, it is also preferred that the male part of the connector comprises a tip.

[0042] The tip is preferably positioned so that the spring contact pin(s), which are arranged, for example, perpendicular to the longitudinal axis of the probe element, is / are protected. In this embodiment, the tip is positioned distally (at the end) so that the male parts of the connector or the male contact elements, e.g., spring contact pins, are located below the tip. The tip allows the connector to be formed when the probe elements are joined without the male parts of the connector being subjected to mechanical stress and damage. The tip is preferably blunt, i.e., frustoconical in shape. This shape allows for an exit hole for a connecting rope and is ideally suited to the proven assembly of avalanche probes.

[0043] A female contact element can be shaped as a contact surface. In a preferred embodiment, female contact elements are shaped as circular or ring-shaped contact surface(s).

[0044] Several concentric, spaced-apart circles can serve as suitable contact or friction surfaces for the corresponding number of spring contact pins, provided these are arranged parallel to the longitudinal axis of the probe element. If the male contact elements are spring contact pins arranged perpendicular to the longitudinal axis of the probe element, suitable female contact elements can be designed as superimposed annular contact surfaces on the inner surface of the probe element's casing. The circular or ring shape ensures that electrical contact is established regardless of the relative direction of rotation between the probe elements.

[0045] In one embodiment, the temperature sensors within a probe element are connected to each other / in contact via a fixed electrical connection, such as a circuit board or cable. The circuit board or cable is preferably also located within the probe element. Within a probe element, temperature sensors and / or electrical connections and contact elements can each be positioned with a support element. This support element can be, for example, a one-piece or multi-piece plastic component. A plastic support element has proven advantageous because the material is lightweight, has minimal impact on heat transfer, and can be manufactured cost-effectively in series.

[0046] Through the described electrical connections and contacts, all temperature sensors can preferably be connected to each other via a single wiring system, controlled and supplied with the electrical current required for temperature measurement.

[0047] In a preferred embodiment, the temperature sensors are controllable via a protocol, the protocol being configured such that multiple temperature sensors connected via a single wiring system can be controlled. The wiring system can comprise multiple wires, preferably two or three, and is controllable, for example, via a one-wire protocol. Thus, the temperature sensors can be controlled internally. Preferably, the control is performed via the central control unit in the head section, which—for example, designed as a microcontroller—can be connected to the temperature sensors via electrical connections and (removable) contacts.

[0048] In one embodiment, the temperature sensors are arranged at a distance D from each other along the length L. The distance D between two temperature sensors can be selected (independently of each other) from the range of approximately 3 cm to 30 cm, preferably 5 cm to 20 cm. Preferably, the temperature sensors are spaced at regular intervals of approximately 5 cm to 20 cm. Thus, in a preferred embodiment, preferably 10 to 40, for example approximately 30, temperature sensors are distributed along the length L of the avalanche probe. A probe element of length 1 of 35 to 60 cm has approximately 2 to 7, for example 4, preferably evenly spaced temperature sensors. Experience has shown that the discussed distances are suitable for depicting a meaningful temperature profile within a snowpack.

[0049] The invention is not limited to specific types of temperature sensors. Suitable temperature sensors include, for example, digital sensors in which components change their resistance with temperature changes. However, optical sensors that detect temperatures using electromagnetic radiation are also conceivable. Besides the number of measuring points and the quality of the temperature sensors themselves, the thermal conductivity of the surrounding material plays a role in temperature determination. To enable the temperature sensors to determine the temperature as accurately as possible, the casing of the probe elements is preferably made of a heat-insulating material. This prevents heat transfer along the probe element from equalizing the temperature between different measuring points and thus distorting the measured temperature.The casing is preferably made of a material with a thermal conductivity of less than 200 W / (mK), preferably less than 100 W / (mK). Therefore, materials such as steel, plastics, and plastic composites are suitable with regard to thermal conductivity and are, for example, preferable to aluminum, which has a high thermal conductivity.

[0050] In a preferred embodiment, the casing is formed from a material belonging to the group consisting of carbon fiber reinforced plastics. The casing is preferably formed from a carbon fiber reinforced plastic with the lowest possible thermal conductivity. Carbon fiber reinforced plastic (colloquially also referred to as "carbon") exhibits high stiffness and flexural strength at a lower weight, the weight being, for example, less than that of a casing made of steel.

[0051] In another preferred embodiment, recesses for the temperature sensors in the casing are sealed with a thermally conductive material. The material can seal the recess for each temperature sensor in such a way that it is flush with the casing. This provides mechanical protection for the temperature sensor, while the thermal conductivity enables a rapid and accurate determination of the ambient temperature. According to the invention, a material is considered thermally conductive if its thermal conductivity is higher than that of the heat-insulating material of the casing.

[0052] Even though no additional sensors or electronics are required for the applications described below, further sensor elements can be integrated into the avalanche probe. For example, EP 1 700623 A1 describes a rod probe for locating buried persons with an electronic locating system, which would also be compatible with the avalanche probe according to the invention. In addition to temperature sensors, the probe element can include other sensors, such as distance sensors, to determine, for example, the distance between the probe head and the surface of the snowpack. Distance sensors can be designed as optical fibers.

[0053] The problem is also solved by a method for recording temperature data using the avalanche probe according to the invention, comprising the steps:

[0054] a) Connecting the majority of probe elements to form an essentially rod-shaped arrangement of length L, which constitutes an assembled avalanche probe,

[0055] b) Inserting the assembled avalanche probe into a snowpack, wherein the length L of the avalanche probe is partially or completely inserted into the snowpack,

[0056] c) Acquisition of raw data at the temperature sensors, wherein the raw data for each measuring point is preferably acquired in the form of a temperature gradient, d) Evaluation or processing of the raw data via i) a control unit which is arranged in the avalanche probe, and / or ii) an external device, wherein at least one temperature profile is generated for at least two temperature sensors with their position along the length L of the avalanche probe,

[0057] e) Optionally, establishing a wireless connection with an external device, preferably a smartphone, and

[0058] f) Optional wireless transmission of the captured or processed raw data to the external device.

[0059] This method describes the application of the avalanche probe according to the invention, wherein temperature data are generated and recorded as a result of the application, in particular in the form of a temperature profile for at least two temperature sensors with their position along the length L of the avalanche probe.

[0060] Step a) represents the first step of the method and corresponds to assembling the avalanche probe, preferably using a clamping device. The assembled avalanche probe, consisting of connected / clamped probe elements, is then at least partially inserted into a snowpack according to step b). Before or after step b), the electronics and the temperature sensor control are activated. This can be achieved by switching on the control unit at the probe head using a circuit after the avalanche probe has been assembled. AT 517066 B1 describes an activation element integrated into the clamping device that automatically activates an electronic location system when the probe is in its clamped configuration. Such a mechanism is also suitable for activating the electronics according to the invention.

[0061] Step c) describes the essential step of temperature measurement, i.e., the acquisition of raw data at the temperature sensors. Once the avalanche probe is inserted into the snowpack and activated, the time-varying temperature gradient and the temperature profile along the route are measured by acquiring raw data.

[0062] For each temperature sensor, the measured temperatures gradually approach the temperature of the snowpack at the corresponding altitude. This temperature equalization occurs according to Newton's law of cooling. For evaluation purposes, the previous temperature value can be compared with the current temperature value at the corresponding temperature sensor (i.e., at the corresponding altitude) for all temperature sensors after each measurement, and a difference can be calculated. Initially, this difference is high, as the temperatures are still equalizing. Over time, this difference decreases. In one embodiment, the microcontroller stores the temperature profile as soon as a certain temperature difference threshold is not exceeded several times consecutively across all temperature sensors.Alternatively, the decrease according to Newton's law of cooling can be fitted into appropriate models using fewer measurement points of the temperature gradient in order to determine the snowpack temperature by extrapolation.

[0063] As mentioned previously, temperature gradients can also be used to determine whether a temperature sensor is surrounded by ambient air or a layer of snow.

[0064] It can be useful for the avalanche probe to continue measuring the temperature at regular intervals after an initial temperature reading has been recorded. The measurement ends automatically when the avalanche probe is withdrawn from the snowpack and switched off. The probe can then be folded up and packed away, making it easy to store, for example, in a bag.

[0065] The evaluation or processing of the raw data is carried out via i) a control unit located in the avalanche probe, ii) an external device, or iii) a combination of both options. For example, determining the point in time at which the raw data is sufficient to record a temperature profile via the at least two temperature sensors positioned along the length L of the avalanche probe can preferably be done in a control unit within the avalanche probe, while further processing, for example with regard to avalanche risk assessment, can be carried out on an external device.

[0066] In preferred embodiments, the method therefore comprises steps for establishing a wireless connection with an external device, for example a smartphone, and for transferring the captured or processed raw data to the external device.

[0067] This allows currently captured or processed raw data to be transmitted wirelessly, for example via Wi-Fi, mobile network, Bluetooth, RFID, or NFC. The captured or processed raw data can then be (further) processed and / or displayed on an external device, such as a smartphone.

[0068] In another aspect, the temperature data recorded according to the invention can be used to predict avalanche risk.

[0069] The temperature data acquired using the inventive method can be integrated into existing systems, such as those used by avalanche warning services, which are designed to consider temperature profiles in snowpacks. Avalanche risk prediction systems provide a risk assessment, which is typically presented as a standardized guideline value and / or an explanatory text about the avalanche risk.

[0070] In a preferred embodiment, however, the temperature data are determined using a separate computer-implemented method for estimating the local avalanche risk. This method essentially relies on evaluating the temperature data acquired according to the invention with a model that has preferably been trained using machine learning and a large number of temperature data from independent measurements. Such an approach has the advantage that the widespread use of the avalanche probe according to the invention generates an ever-growing training set that can be easily used to improve the model.

[0071] The invention therefore also relates to a computer-implemented method for estimating a local avalanche risk, wherein

[0072] a set of temperature data is taken into account, wherein the temperature data each comprise temperature gradients for at least two temperature sensors with their position along the length L of an avalanche probe,

[0073] the set of temperature data is evaluated with a model, wherein the model, preferably using machine learning, has been trained with a large number of temperature data from independent measurements and

[0074] The model provides a risk assessment of the local avalanche risk for the set of temperature data.

[0075] The predictive accuracy of the risk assessment can be improved by considering not only temperature data but also the geographic location and additional data points such as slope angle, time of day, aspect, and ambient temperature. Advantageously, the avalanche probe or a computer-implemented method for estimating the local avalanche risk can also be configured to acquire this data automatically or through user input. In one embodiment, the temperature data set further includes the geographic location of the avalanche probe, and the risk assessment for the local avalanche risk is displayed at the geographic location of the probe.

[0076] DETAILED DESCRIPTION OF THE INVENTION

[0077] Further advantages and details of the invention are explained below with reference to the following figures and examples, without these being to be understood as limiting.

[0078] They show:

[0079] Figs. 1a, b, c Front view and spatial representation of the interior of a probe element of an avalanche probe according to the invention. Figs. 2a, b Side view and spatial representation of a probe element of an avalanche probe according to the invention.

[0080] Fig. 3a, b, c Side view, front view and spatial representation of the interior of a probe element of an alternative embodiment of an avalanche probe according to the invention.

[0081] Fig. 4a, b, c Side view, front view and spatial representation of a probe element of an alternative embodiment of an avalanche probe according to the invention. Fig. 5a, b, c Side view, front view and spatial representation of the electronics of a head part of an avalanche probe according to the invention.

[0082] Fig. 6a, b, c Side view, front view and spatial representation of a head part of an avalanche probe according to the invention.

[0083] Example 1 - Description of the prototypes shown in the figures

[0084] A first and preferred embodiment of the probe element 1 of an avalanche probe according to the invention is shown in Figures 1a to 2c and 2a, 2b, where Figures 1a to 2c illustrate the inner region 10 of the probe element 1. The probe element 1 consists of a casing 110 shown in Figure 2 and an inner region 10 shown in Figure 1.

[0085] Figure 1a shows a front view of the interior 10 of the probe element 1. The interior 10 comprises four temperature sensors 101, which are connected to each other via a circuit board 102. A first temperature sensor 101 is arranged near an upper end of the probe element 1 and soldered to the circuit board on the back. This arrangement allows the inner diameter at the upper end of the probe element 1 to be smaller than the inner diameter of the rest of the probe element 1, which is desirable with regard to the plug connection. A multi-part plastic element 103 positions the temperature sensors 101 and the circuit board 102. The parts of the plastic element 103 are essentially designed as vertical, tubular cylindrical sectors. In the embodiment shown, the plastic element 103 is multi-part, and the individual parts can be connected via a connection, preferably a screw connection.For such a screw connection, the parts of the plastic element 103 can each have a recess 107 on the outer surface of the plastic element 103. Alternatively, a one-piece design of the plastic element can be advantageous. At one lower end, the plastic element 103 is divided into an upper and lower hollow section by an integrated partition plate. This partition plate serves, on the one hand, as a boundary for the circuit board 102 and, on the other hand, allows for the separation of a circular cylindrical recess 106, which is formed by the lower hollow section.

[0086] The recess 106 represents the female part for a plug connection, and the contact surfaces within it serve as the female element for an electrical contact. The contact surfaces are essentially strip-shaped in two dimensions and extend in a ring shape over the entire inner circumference of the recess 106. To form such contact surfaces, for example, a flexible circuit board with two or three bar-shaped contact surfaces is rolled into a cylindrical shell, inserted into the recess 106, and connected to the circuit board 102.

[0087] The upper end of another identical probe element 1, with a male connector, can be inserted into the recess 106, which is located at a lower end of the probe element 1. In the illustrated embodiment, the upper end has a tip 105, which is shaped in a frustoconical form, this frustoconical shape having a circular cylindrical recess 109. A connecting cable can be passed through this recess 109. The male contact element 104 is located below the tip 105. The male contact element 104 is connected to the circuit board 102 and is designed in the form of two pogo pins. These two pogo pins are positioned almost at right angles to the longitudinal axis of the supporting plastic element 103, and thus of the probe element 1, and are spaced apart vertically.

[0088] The inner section 10 of the probe element 1 is inserted into a casing 110, which encloses the inner section 10 like a shell. The complete arrangement of the probe element 1 is shown in Fig. 2a, b. The casing 110 is made of a non-thermally conductive material, such as carbon. In Fig. 2a, it can also be seen that the tips of the two pogo pins protrude slightly beyond the edge of the base of the frustoconical tip 105. This partially protects the pogo pins from potential damage when assembling the avalanche probe. At the same time, contact with a contact surface remains possible, with the pogo pins coming into contact with an identical probe element 1 as soon as a tensioned, i.e., assembled, state is reached between the two probe elements 1.The contact surface can also consist of two strip-shaped surfaces extending over the entire circumference of the recess 106. These two strip-shaped surfaces are spaced vertically apart, with a distance approximately corresponding to the distance between the two pogo pins of the male contact element. An analogous configuration is possible for three pogo pins and three strip-shaped surfaces forming the contact area. It should be emphasized that the contacts encircle the entire circumference, thus allowing a 360-degree connection.

[0089] Furthermore, the casing 110 has recesses 111, which are preferably circular. These recesses 111 are aligned with the respective temperature sensors 101, which are arranged in the interior 10. The recesses can be filled with a thermally conductive material. The material can, for example, be introduced as a thermally conductive paste and thus connect the temperature sensors 101 to the recess 111 and to the casing 110. The non-thermally conductive casing 110 and the recesses 111 filled with thermally conductive material ensure that the temperature sensors 101 can only detect temperature data at the level at which they are arranged.

[0090] An alternative embodiment for the probe element 1 is shown in Figures 3a to 4c. This embodiment differs from the embodiment shown in Figures 1 and 2 primarily in the design of the electrical contact elements. Here, too, the plastic element 112 is essentially designed as a vertical, tubular cylindrical sector, but it has a contact surface at its lower end, which is designed as a perforated disc 113. Circular sliding contacts are arranged on the outward-facing surface of the perforated disc as the female contact element. The male contact element 104 is designed in the form of two pogo pins, with the pogo pins being arranged at the upper end of the probe element 1 parallel to the longitudinal axis of the probe element. However, the two pogo pins are radially spaced apart from each other.These pogo pins, when connected to an identical probe element 1, engage the perforated disc 113 at the lower end of the plastic element 112. The pogo pins make contact with the annular contact surfaces, which are arranged concentrically around a central hole in the perforated disc 113. The radial distance between the annular surfaces corresponds approximately to the distance between the pogo pins. A first circular hole is arranged in the center of the perforated disc 113 to allow a connecting cable to pass through. Figures 5a to 6c show a head section 12 of an avalanche probe according to the invention with a control unit 120. Shown in Figure 6, but hidden in Figure 5, is a housing 121 that encloses the head section 12 and can, for example, be designed similarly to the grip of a ski pole. The head section 12 sits directly on the casing 110 of a probe element 1. Inside the housing 121, as shown in Figure 6, a control unit 120 is located.As shown in Figures 5a to 5c, the electronics for operating the temperature sensors 101 are arranged. The headpiece 12, or rather the electronics within the headpiece 12, is thus configured as a control unit 120 or switching unit for the avalanche probe. The control unit 120 is, for example, implemented as a microcontroller. Furthermore, in this configuration, the headpiece 12 includes a charging socket 122, through which a battery 123 can be charged. Additionally, a switch 124 is mounted externally on the headpiece 12, for which the electronic components for the switch 124 circuit are located internally within the housing 121 as part of the control unit 120. The electronics are connected to, or can be connected to, the temperature sensors 101 via a one-wire protocol and a connecting cable, and can operate them. To connect the control unit 120 to the temperature sensors 101 of other probe elements 1, a plug connection is established between all elements.

[0091] The head section 12 shown in Figures 5a to 6c also includes a tensioning device 125 for a connecting cable, which in a preferred embodiment (independent of the control unit 120) can be arranged on the head section 12. The connecting cable is suitable for facilitating the assembly of the probe elements. During the process of tensioning the connecting cable using the tensioning device 125, the elements of the avalanche probe are arranged one another via the connecting cable in such a way that a tensioned state is created. In order for the connecting cable to tension the avalanche probe, a first end of the connecting cable is connected to the probe element 1. In the preferred case, where several probe elements 1 are connected to one another, the first end of the connecting cable is connected to the lowest probe element 1. Another end of the connecting cable is connected to a tensioning device 125, which is arranged in the head section 12.The tensioning device 125 is configured such that the head section 12 and the probe elements 1 are held connected to each other in a tensioned state when the connecting cable is taut. In this state, the avalanche probe according to the invention can have a length L of 240 cm. Furthermore, the temperature sensors 101 are arranged at a distance D along the length L in this tensioned state. The distance D between the temperature sensors can be, for example, 5 to 10 cm. The tensioning device 125 is also configured such that the connecting cable can be released again, so that the head section 12, which carries the probe element 1, and the other probe elements 1 are movable relative to each other in a released state. In the tensioned or connected state, the male contact elements 104 are in contact with the contact surfaces.This connection enables the operation of the temperature sensors 101 and the connection of the temperature sensors 101 to the electronics or the control unit 120.

[0092] Example 2 - Application of the avalanche probe to record a temperature profile

[0093] To record a temperature profile in a snowpack using one of the avalanche probes described in Example 1, the following sequence can be performed:

[0094] 1. The avalanche probe is removed from its casing in its folded state. By ejecting it and pulling on the connecting cord, the avalanche probe extends to its full length L, and the data connection between the individual temperature sensors 101 is established during the retraction process.

[0095] 2. The avalanche probe is switched on via the head unit 12. It starts measuring automatically, so no further setup is necessary.

[0096] 3. The avalanche probe is inserted into the snowpack until it reaches the ground. If the probe cannot be inserted to its full length, e.g., 240 cm, the remaining portion stays above the snow surface. 4. The avalanche probe begins continuously measuring temperature data.

[0097] 5. Over time, the measured temperatures change and become increasingly similar to the temperature of the snowpack at the corresponding altitude.

[0098] 6. With each measurement, the previous temperature value is compared to the current temperature value at the corresponding level for all temperature sensors, and a difference is calculated. Initially, this difference is high as the temperature equalizes, but it decreases over time. The temperature equalization occurs according to Newton's law of cooling.

[0099] 7. The temperature difference serves as an (additional) variable for a function to determine the time difference between the individual measurements.

[0100] 8. If a certain temperature difference threshold is not exceeded several times in succession across all temperature sensors 101, the microcontroller saves the temperature profile of the last measurement. After switching on, the user can connect a device to the avalanche probe via Bluetooth or similar technology and will receive information, for example in an app on the device, that data is still being measured. Once step 8 is complete, the temperature profile is sent to the device and the app at regular intervals.

[0101] The avalanche probe continues to measure temperature differences at regular intervals. Each transmission of the temperature data thus transmits the actual current temperature value.

[0102] The temperature profile is displayed and can be used by experts to measure the avalanche snow profile. Furthermore, the raw data can be exported for import into existing systems, e.g., by the avalanche warning service.

[0103] Once the data has been received, the avalanche probe can be pulled out of the snowpack and switched off.

[0104] By folding and packing it up, a lightweight and compact device is created that can be stored in a bag.

Claims

REQUIREMENTS 1. Avalanche probe for comprehensive snowpack analysis: a plurality of elongated probe elements (1) which can be detachably connected to one another via a plug connection to form an essentially rod-shaped arrangement of length L, • wherein the probe elements (1) each have an outer, essentially tubular shell (110), • wherein at least individual probe elements (1) each have at least one temperature sensor (101), preferably three to four temperature sensors (101), and • the avalanche probe has at least two temperature sensors (101) which, when the probe elements (1) are connected, are arranged at a distance D along the length L, the avalanche probe is characterized by the fact that the temperature sensors (101) are arranged within the shell (110) of the respective probe element (1), and the shell (110) has a recess (111) for each temperature sensor (101), wherein the respective temperature sensor (101) is arranged in the alignment of the recess (111).

2. Avalanche probe according to claim 1, characterized by a head part (12) which has a control unit (120) and a housing (121), preferably designed as a handle.

3. Avalanche probe according to claim 1 or 2, characterized in that the plug connections are each configured in such a way that a detachable electrical contact is formed which enables the transmission of data.

4. Avalanche probe according to claim 3, characterized in that the plug connections are each configured such that the electrical contact is formed independently of the relative direction of rotation between probe elements (1).

5. Avalanche probe according to any one of claims 1 to 4, characterized in that a probe element (1) has at least at one end a male contact element (104) which comprises at least one, preferably two or three, spring contact pin(s).

6. Avalanche probe according to claim 5, characterized in that the end of the probe element (1) which has a male contact element (104) comprises a male part of the plug connection with a tip (105), wherein the tip (105) is preferably arranged such that the male contact element (104) is protected, and wherein the tip (105) is preferably frustoconical in shape.

7. Avalanche probe according to one of claims 3 to 6, characterized in that a probe element (1) has at least at one end a female contact element which is shaped as an annular and / or circular contact surface.

8. Avalanche probe according to one of the preceding claims, characterized in that the casing (110) is formed from the group consisting of carbon fiber reinforced plastics.

9. Method for recording temperature data using an avalanche probe according to any one of claims 1 to 8, comprising the steps: a) Connecting the plurality of probe elements (1) to form a substantially rod-shaped arrangement of length L, which constitutes an assembled avalanche probe, b) Inserting the assembled avalanche probe into a snowpack, wherein the length L of the avalanche probe is partially or completely inserted into the snowpack, c) Acquiring raw data at the temperature sensors (101), wherein the raw data for each measuring point are preferably acquired in the form of a temperature gradient, d) Evaluation or processing of the raw data via i) a control unit (120) arranged in the avalanche probe, and / or ii) an external device, wherein at least one temperature profile is generated for at least two temperature sensors (101) with their position along the length L of the avalanche probe, e) Optionally, establishing a wireless connection with an external device, preferably a smartphone, and f) Optional wireless transmission of the captured or processed raw data to the external device.

10. Method according to claim 9, further comprising a step, (g) Predictions of a local avalanche risk using temperature data recorded as a temperature trend, wherein the step to predict a local avalanche risk represents a risk assessment, where step g) is preferably performed in an external device.

11. Computer-implemented method for estimating local avalanche risk, wherein a set of temperature data is taken into account, wherein the temperature data each comprise temperature gradients for at least two temperature sensors with their position along the length L of an avalanche probe, the set of temperature data is evaluated with a model, wherein the model, preferably using machine learning, has been trained with a large number of temperature data from independent measurements and The model provides a risk assessment of the local avalanche risk for the set of temperature data.

12. Computer-implemented method according to claim 11, characterized in that the set of temperature data further includes the geographical location of the avalanche probe, and the risk assessment for the local avalanche risk at the geographical location of the avalanche probe is reproduced.

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