EP4281196A1

EP4281196A1 - Adaptive counter-current system for a swimming pool

Info

Publication number: EP4281196A1
Application number: EP22702903.0A
Authority: EP
Inventors: Jan Van Loon
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-22
Filing date: 2022-01-21
Publication date: 2023-11-29
Also published as: NL2027375B1; WO2022157335A1

Abstract

A system for a counter current swimming pool, the system comprising a counter current swimming device; a processing device; a detection device, and a light output signal module; wherein the processing device is configured to, during operation of the system: obtain a signal representing a swimmer's position from the detection device; cause the counter current device to adjust a water output of the counter current swimming device based on the swimmer's position; and cause a light output of the lighting device to change based on the swimmer's position.

Description

Adaptive counter-current system for a swimming pool

Field of the invention

[0001] The invention relates to a counter current system for a swimming pool.

Background of the invention

[0002] Traditional counter current swimming pool systems have a counter current swimming device which creates water currents. in a swimming pool in a direction opposite to a swimmers direction of travel. The water flow creates extra resistance, creating a challenge for the swimmer to maintain his/her swim in that direction. This is particularly beneficial for swimmers (and users alike) for training, therapy or exercising purposes.

[0003] Known counter current swimming devices allow the swimmer to configure the direction and magnitude of the current before the swimmer enters the pool. Recently, as shown in FR 2822183 A1 , improvements have been made to a counter current swimming devices to automatically adapt the current based on the progress of the swimmer in the swimming pool. Such systems incorporate camera’s that detects the position of the swimmer and adapts the current based on the detected position. Also, as shown in US 2017/0191281 A1, a transmitter, operated by a trainer (person outside of the swimming pool) could also be used to adjust the flow rate of a counter current swimming device.

[0004] While such systems allow the swimmer to swim against varying water flow, the swimmer may also want to be informed about their progress of the current training, therapy or exercise. In order to find out, the swimmer would either have to interrupt their session and check, for example, by asking someone (such as a trainer). The counter current swimming pool system may then detect that the swimmer has slowed down, and as a result may reduce the water flow, which may lead to inaccurate training, exercise or therapy results.

[0005] US 2016/0038815 A1 describes how change indicators can be used to indicate any upcoming changes to the exercise of a swimmer. For example, a set of lights is placed at the bottom of a pool, close to one edge of said pool, indicating that the swimmer has reached a predetermined distance (or time interval) and a transition (such as the swimmer performing a wall turn manoeuvre) is upcoming. Such indicators are operatively connected with the counter current swimming device so that, in the case the swimmer will perform the wall turn manoeuvre, the counter current swimming device powers down so that the swimmer can approach the wall and perform said manoeuvre. Such indicators can also be used to inform the swimmer that the velocity of flow or direction of the water current has changed. The predetermined distance is calculated using the velocity of the current generated by the counter current device and the elapsed time. A tracking system can also be employed by the counter current swimming pool system to track the position of the swimmer, and is operatively connected to adjust the velocity of flow or direction of the current based on the tracked position of the user.

[0006] In such counter current swimming pool systems, the simulation of the pool length (i.e. the predetermined distance) is calculated based on the output of the counter current swimming device, where the swimmer is one of the input variables (position tracking information). This leads to discrepancies between the simulation and real-life pool lengths if the swimmer does not swim in manner which the counter current swim device considers optimal. For example, the swimmer may initially swim along a line parallel to the central axis of water flor from the counter current swimming device. In such cases, the swimmer is in fact swimming against a weaker (slower) current than what is recorded. While the position tracker may compensate for this by adjusting flow velocity and direction of the counter current swimming device, the flow direction will not be perfectly opposite to the direction of swim. This may also lead to faulty change indicators, as the simulated swim distance will not be the same as the actual distance swam by the swimmer, and the swimmer must therefore perform transitions earlier or later than expected.

[0007] There is therefore a need for an accurate means for adjusting the counter current swimming device.

Summary of the invention

[0008] According to a first aspect, the invention provides a counter current swimming pool system comprising a counter current swimming device; a processing device; a detection device, and a light output signal module, wherein the processing device is configured to, during operation of the system: obtain a signal representing a swimmer’s position from the detection device; cause the counter current device to adjust a water output of the counter current swimming device based on the signal of the swimmer’s position; and cause a light output of the lighting device to change based on the signal. The operation of said counter current swimming pool system therefore relies on the position input of the swimmer, and not the water flow (output) of the counter current swimming device.

[0009] In an embodiment, the detection device comprises a sonar device, preferably located in the counter current swimming device. As sonar waves are unaffected by the movement of water, it is possible to obtain an accurate measurement of the swimmers position. This allows the counter current swimming device to take its own measurements related to the position of the swimmer and adjust the water output accordingly.

[0010] In an embodiment, the detection device comprises a laser device, preferably located in the counter current swimming device

[0011] In an embodiment, the detection device comprises a portable device worn by the swimmer. As the detection device is attached onto the user, a more accurate reading of the positional information relating to the swimmer can be obtained.

[0012] In an embodiment, the detection device comprises a camera. The camera is able to capture more information regarding the swimmers position in one image which could be used to further adjust the water output of the counter current swimming device.

[0013] In an embodiment, the camera is located in the counter current swimming device. This allows said device to automatically adjust the water flow output based on the position of the swimmer.

[0014] In an embodiment, the camera is configured to generate images which are processed by a deep learning system for detecting the swimmer. A deep learning system may be able to track the progression of the swimmer throughout the exercise regime, and may output information such as inconsistencies in the swimmers form, make recommendations to optimize every stroke, and so on.

[0015] In an embodiment, the processing device is configured to detect an object in the pool and to raise an alarm in response thereto. While the generation of an artificial water current may be beneficial to the swimmer, it may be a problem for other users using the pool. In order to prevent accidents (such as drowning), the processing device detects any objects, other than the user, entering the pool and to raise an alarm (or even stop the system altogether) in response thereto.

[0016] In an embodiment, the processing device calculates an effective cumulative distance swum by the swimmer based on the cumulative position displacement of the swimmer. By keeping track of the positional changes of the swimmer, the system is able to record the effective cumulative distance swam by the swimmer. [0017] In an embodiment, the light output signal module outputs a light signal based on the calculated effective distance. After a predetermined distance (or time interval) is reached, such light signals may inform the swimmer of the completion of a task. Furthermore, such light signals may also inform the swimmer of the distance covered or the elapsed time., so the swimmer is aware may adjust factors, such as his/her tempo.

[0018] In an embodiment, the light output signal module further outputs a further light signal when the calculated effective distance reaches a predetermined value. An additional light signal may indicate, among others, the remaining distance (or time), or any information that may be of use to the swimmer during the exercise.

[0019] In an embodiment, the alarm configured to transmit a first signal when the object, other than the swimmer, enters the counter current swimming pool. This will alert not only the swimmer, but also others around the swimming pool.

[0020] In an embodiment, the alarm is configured to transmit a second signal when the object, other than the swimmer, is positioned less than a predetermined value from the swimmer’s position. This is to prevent collisions between the swimmer and the object.

[0021] In an embodiment, the first and second signals are is at least one of an audio signal, a visual signal, and a haptic signal. Using a variety of signals allows for the customization of the alarm, allowing for the alarm to have implication(s) to a select group of people.

Brief description of the Figures

[0022] Embodiments of the present invention will be described hereinafter, by way of example only, with reference to the accompanying drawings which are schematic in nature and therefore not necessarily drawn to scale. Furthermore, like reference signs in the drawings relate to like elements.

[0023] Figure 1 schematically shows the counter current swimming pool system.

[0024] Figure 2 schematically shows the mapping between the water flow rate based on the swimmers distance to the counter current swimming device.

[0025] Figure 3 schematically shows the position of the lights in the swimming pool.

[0026] Figure 4 schematically shows a flowchart depicting a light signal generation method of the counter current swimming pool system.

[0027] Figure 5 schematically shows a configuration of a counter current swimming system in a swimming pool comprising lights, external camera and an alarm device. [0028] Figure 6 schematically shows the configuration when there is a plurality of counter current swimming systems and lights.

[0029] Figure 7 schematically shows a flowchart depicting a method to display the difference between the received flow data and the stored flow data.

[0030] Figure 8 schematically shows the mapping between the different light outputs based on the distance covered and the elapsed time.

Detailed description

[0031] Figure 1 schematically shows the counter current swimming pool system (100) .The counter current swimming pool system (100) may comprise a counter current swimming device (101), a processing device (102), a detector device (103) and a light output signal module (104). The various components may be electrically connected to one other, however they can also be wirelessly connected to each other.

[0032] In an embodiment of the present invention, the processing device (102) in the counter current swimming pool system (100) is configured to receive signals from the detector device (103), and adjusts a water output of the counter current swimming device (101) based on the received signal and adjusts a light output of the lighting device.

[0033] The signal transmitted from the detector device (103) is at least one of an electronic transmission signal, a wireless communication signal, or even a mechanical signal.

[0034] The detector device (103) is configured to detect the position of the swimmer in the swimming pool in the following manner.

Option A: Distance from the counter current swimming device (101)

[0035] In this embodiment, the detector device (103) is configured to detect the swimmer, and calculate their position with respect to the position of the counter current swimming device (101). Preferably, this calculation is made from an opening section of the counter current swimming device (101) - also known as a mouth - from which water is output into the swimming pool to a leading edge of the swimmer.

[0036] In a preferred embodiment, the water output, known as the water flow, of the counter current swimming device (101) is adjusted to maintain a pre-determined distance between the swimmer and the counter current swimming device (101). An example of this is shown in Figure 2. Figure 2 an embodiment of the flow distance curve (21) of the present invention. The swimmer may start their exercise at a distance ds. At the distance ds, the counter current swimming device (101) may be configured to output an initial water flow. The initial water flow may be a fixed value but could also be zero. As the swimmer swims towards the counter current swimming device (101) the change in the distance is obtained by the detection device (103) which then transmits a signal to the counter current swimming device (101) to increase the water flow in the direction of the swimmer. When the swimmer is at a distance d2, which is closer to the counter current swimming device (101), the detection device (103) transmits a signal to output the maximum water flow in the direction of the swimmer. If a swimmer is at a distance less than a distance di , which is closer to the counter current swimming device (102) than both d2 and ds, the detection device (103) may be configured to signal the counter current swimming device (101) to stop the water flow. This may be performed so that the swimmer does not get caught in any moving components of the counter current swimming device (101), and therefore avoids injury. In other words, the detection device (103) and the counter current swimming pool system (100) as a whole may be configured to include a safety mechanism to prevent injury or risks.

[0037] Conversely, if the swimmer is at a distance d4, which is further a distance further away from the counter current swimming device (101) than d1 , d2 or d3, the detection device (103) may be configured to reduce the water flow to zero (23) or to maintain the initial water flow (22) to allow the swimmer to continue swimming at the initial water flow..

Option B: Displacement from a fixed point in the swimming pool

[0038] In this embodiment, the detection device (103) is configured to determine the starting position of the swimmer in the exercise. If the detection device (103) detects the swimmer is moving towards the counter current swimming device (101), the detection device (103) may be configured to transmit a signal to the counter current swimming device (101) to increase the water flow in the direction of the swimmer. If the detection device (103) detects the swimmer is moving away from the counter current swimming device (101), the detection device (103) may be configured to transmit a signal to the count current swimming device (101) to reduce the water flow in the direction of the swimmer. If the detection device (103) detects the swimmer is moving in a lateral direction relative to the counter current swimming device (101), the detection device (103) may be configured to rotate or displace the counter current swimming device (101) in the direction of the swimmer. This allows the counter current swimming device to adjust its water output based on the swimmer’s position.

[0039] In an embodiment of the present invention, the detection device (103) comprises a camera and is positioned inside the counter current swimming system (100). This results in an all-in-one system that is also portable. Furthermore, this allows a counter current swimming device (101) to determine the distance between itself and the swimmer.

[0040] In an embodiment of the present invention, the detection device (103) comprises a portable device worn by the swimmer. This allows the detection device to not only collect position information of the swimmer, but also information of the swimmer (swimming stroke count, heart rate, distance covered). When the portable device worn by the swimmer is configured to obtain the heart rate of the swimmer, the processing device is further configured to obtain a signal of the swimmers position based on a combination of the detected position and the heart rate of the swimmer. As an example, when the heart rate of the swimmer is higher than a predetermined value (when the swimmer is training), the processing device may adjust the water flow by increasing its output, whereas when the heart rate of the swimmer is below a predetermined value (when the swimmer is warming up/cooling down/relaxing), the processing device may lower the water flow. The opposite is also possible - when the heart rate of the swimmer is above a predetermined value (when the swimmer overexerts), the processing device may lower the water flow, and when the heart rate of the swimmer is below a predetermined value (when the swimmer is about to start training), the processing device may increase the water flow. The portable device may comprise a water-proof housing, which is attached to the swimmer, wherein a transmitting means is positioned in the water proof housing. The water proof housing may be, among others, a bracelet, a ring, a watch or smartwatch.

[0041] In order to obtain position information, the detection device (108) may comprise of a global positioning system (GPS) device to determine the position of the swimmer relative to the counter current swimming system (100). The counter current swimming system (100) may also include a GPS device in communication with the processing device (102) to determine its position. In another embodiment, sonar may be used by the counter current swimming system (100) to calculate the distance between the system (100) and the swimmer.

[0042] When sonar is used by the counter current swimming system (100) to calculate the distance between the system (100) and the swimmer, the counter current swimming system performs an initial calibration step in order to fine-tune the sonar.

[0043] The method of calibration is as follows. In Step 1001 , the swimmer is positioned at the fixed point in the swimming pool. In Step 1002, a sonar module in the detection device performs an initial sweep. In Step 1003, the sonar module is configured to adjust the distance measurements. Steps 1002 - 1003 may be repeated until the position accuracy is below a minimum threshold. Optionally, in step 1003, the sonar module is configured to communicate with an external device, which is configured to adjust the distances externally. As sonar performs independent of the waves and flow of water, it is suited to measure underwater distances.

[0044] Using sonar, the counter current swimming system (100) may also perform calibration during the operation of said counter current swimming system (100). The detection device may determine that the positon of the swimmer is displaced from the fixed position in the swimming pool above a predetermined threshold, and then performs calibration steps 1002 and 1003, optionally repeatedly, until the displacement is below a minimum threshold. In this manner, the accuracy of the position measurement is maintained above a certain degree.

[0045] When an external device is used when performing the calibration, the external device may comprise a display and an input/output module. When in step 1002, upon reception of the sonar data from the sonar module, the external device is configured to display the sonar data on the display. An external user may then, using the provided information, transmit a signal to the detection module to adjust the water flow of the counter current swimming device.

[0046] When the detection device comprises a laser, a similar method of calibration is performed. In Step 1101 , the swimmer is positioned at the fixed point in the swimming pool. In Step 1102, a laser module in the detection device is positioned such that the laser is directed towards the swimmer. In step 1103, the laser module is configured to adjust the distance measurements. Steps 1102 - 1103 may be repeated until the position accuracy is below a minimum threshold. Optionally, in step 1103, the sonar module is configured to communicate with an external device, which is configured to adjust the distances externally.

[0047] In another embodiment of the present invention, the counter current swimming system (100) is connected to lights (31) positions around the edges of the swimming pool (30), as shown in Figure 3. The lights (31) mentioned herein are either singular lights or multiple lights. While the lights may be positioned along the edges of the swimming pool (30) in order to maintain a fixed position, the lights may also be placed in the water at set distances and depths by means of, for examples, cables, mounts or even propulsion systems which maintain the position of the light (31).

[0048] Based on the position of the swimmer in the swimming pool, determined based on at least one of options A or B described above, the detection device (103) is configured to transmit a signal to the light output signal module (104) in the counter current swimming system (100) to adjust the output of the lights (31) connected to the light output signal module (104).

[0049] The variation in the light output is described as follows:

[0050] Variation 1 : Light intensity

[0051] In this embodiment, the intensity of the output light is varied according to the position of the swimmer. When the swimmer swims towards the counter current swimming device (101), the light output signal module (104) may be configured to increase the light intensity of the lights. When the swimmer swims away from the counter current swimming device (101), the light output signal module (104) may be configured to reduce the light intensity.

[0052] In another embodiment, when multiple lights (31) are used, the light output signal module (104) may be configured to vary the light intensity for a subset of lights (31) in the swimming pool. When the swimmer swims in a lateral (i.e. side-to-side) direction, the lights on one edge of the pool may output a different light intensity to the lights on another edge of the pool. In an embodiment, when the swimmer swims towards a direction perpendicularly right to the direction towards an edge of the swimming pool (30), the light output signal module (104) may be configured to increase the intensity of the lights on the edge to which the swimmer is swimming towards, and reduce the lights on the edge to which the swimmer is swimming away from.

[0053] While the above embodiments describe that the light intensity increased when the swimmer is moving towards either an edge of the swimming pool (30) or to the counter current swimming device (101), the light output signal module (104) may also be configured to reduce the lights in such cases, whereby lights on the edge of the swimming pool the swimmer is swimming away from could then be configured to increase in light intensity.

[0054] Such variations in light intensity allows the swimmer to determine their location in the swimming pool.

[0055] Variation 2: Light wavelength

[0056] In this embodiment, the wavelength of the output light is varied according to the position of the swimmer. Preferably, the wavelength may be limited to the visible spectrum.

[0057] When the swimmer swims towards the counter current swimming device (101), the light output signal module (104) may be configured to increase the wavelength of the output light of the lights (31). In other words, the light becomes more red in colour. When the swimmer swims away from the counter current swimming device (101), the light output signal module (104) may be configured to reduce the wavelength of the output light of the lights (31). In other words, the light becomes more violet in colour.

[0058] In another embodiment, when multiple lights (31) are used, the light output signal module (104) may be configured to vary the wavelength of light for a subset of lights (31) in the swimming pool. When the swimmer swims in a lateral (i.e. side-to- side) direction, the lights on one edge of the pool may output a different wavelength to the lights on another edge of the pool. In an embodiment, when the swimmer swims towards a direction perpendicularly right to the direction towards an edge of the swimming pool (30), the light output signal module (104) may be configured to increase the wavelength of the output light on the edge to which the swimmer is swimming towards, and reduce the wavelength of the output light on the edge to which the swimmer is swimming away from.

[0059] While the above embodiments describe that the wavelength of the output light increased when the swimmer is moving towards either an edge of the swimming pool (30) or to the counter current swimming device (101), the light output signal module (104) may also be configured to reduce the wavelength of the output light in such cases, whereby lights on the edge of the swimming pool the swimmer is swimming away from could then be configured to increase the wavelength of output light.

[0060] Such variations in the wavelength of the output light allows the swimmer to determine their location in the swimming pool. As the chromatic scale is more developed, it is possible for smaller variations in the position of the swimmer to be output by the lights.

[0061] Variation 3: Patterned lights

[0062] In this embodiment, a plurality of lights (31) in the swimming pool are used to convey patterns to the swimmer. Such patterns may include lights configured to output light in a pre-determined pattern, a light configured to output an arrow instead of standard uniform light, a plurality of lights positioned to form an arrow, or even a light configured to output a message.

[0063] Figure 4 shows a light signal generate method (40) according to an embodiment of the present invention. The light signal generate method (40) may be performed by the light output signal module (104) but may also be performed remotely. [0064] In the light signal generate method (40), in step 41 a current status is output by the lights. The current status may include the position of the swimmer, the elapsed time from the start of the exercise, or information regarding the swimmer obtained by the detector device (103). The information includes, but not limited to, the swimmers heartbeat, blood-oxygen level, maximal oxygen consumption rates (such as V02max measurements), the height of the swimmer, the weight of the swimmer, the detected swimming stroke type.

[0065] In step 42, the current status is compared to a preset exercise template (or program). Such preset exercise may include, but not limited to, a total distance covered, the swimming pattern in the swimming pool, a target swim speed, a achieved milestone (such as calories burned). Such preset exercise template may also include a heartbeat level, wherein the preset exercise template is triggered when the heartbeat of the swimmer exceeds (or falls below) the heartbeat level.

[0066] When the current status and the preset exercise template matches, the light signal generate method (40) proceeds to step 43. Otherwise, the method (40) returns to step 41.

[0067] In step 43, the light signal generate method (40) is configured to output a signal indicating that the preset exercise template has been reached. In an embodiment, this output may be performed by a blinking of a light (31) (a determined pattern), but can also be performed by the patterns mentioned above. The light signal generate method (40) then returns to step 41 where the current status is output.

[0068] While different pattern possibilities have been described in the above embodiment, such light patterns may also include a combination of variations 1 and 2 described above.

[0069] In another embodiment, the detection device (103) comprises an external camera (51) connected to the counter current swimming system (100) as shown in Figure 5. This allows the counter current swimming system (100) to have an alternative viewpoint of the swimmer in order to obtain a more accurate distance measurement. Such external camera may be mounted above the swimming pool, underwater at the edge of the swimming pool, at the bottom of the swimming pool, or around the swimming pool.

[0070] In an embodiment, the detection device (103) comprises the external camera (51) and an alarm device (52) configured to detect an object in the pool and to raise an alarm in response thereto. When an object, other than the swimmer, enters the swimming pool, the object may not be aware that a counter current is present in the swimming pool. Therefore, the system has a means for alarming the people involved. [0071] In an embodiment, when the external camera(51) is used to determine the position of the swimmer, the external camera (51) is further configured to monitor the surroundings of the swimmer. If an object is positioned too close to the swimmer, which may lead to injuries. In order to prevent such incidents and/or catastrophes, the alarm device (52), once the detection device (103) detects an object, is configured to sounds an alarm. Such alarms may include audio signals, visual signals (such as changing light output of the lights (31)) as well as haptic signals.

[0072] In an embodiment, when the external camera (51) is not used to determine the position of the swimmer, the external camera (51) is configured to monitor the swimming pool and its surroundings, and sounds an alarm if it detects an object trying to enter the pool. Such alarms may include audio signals, visual signals (such as changing light output of the lights (31)) as well as haptic signals. This acts as a security system for the pool, and prevents objections, such as infants, accidentally entering the pool without supervision, which may lead to drowning. The alarm system is configured to warn those people involved to reduce the risk of injuries.

[0073] Figure 6 shows an embodiment where multiple counter current swimming systems (100) are positioned in the swimming pool comprising multiple lights (31).

[0074] When the counter current swimming systems (100) are positioned along the same edge of the swimming pool, they systems (100) may communicate with each other to determine which lights (31) are operated by which system (100). For example, a first system (100) is configured to operate the lights to the edge adjacent to the first system, (100) and the second system (100) is configured to operate the lights to the edge adjacent to the second system (100).

[0075] When the counter current swimming systems (100) are positioned along opposite edges, the systems (100) may be configured such that only one of the systems (100) operates the lights (31). This prevents the transmission of mixed light outputs, which may lead to confusion in the swimmer.

[0076] In an embodiment of the present invention, the counter current swimming system (100) is configured to store the information regarding the past and current flow rate of the counter current device and/or of the relative position of the swimmer. Keeping track of this and other collectible data allows the system (100) to keep track of information such as the total distance covered (known as effective cumulative distance), average speed throughout the exercise, average heartbeat, total elapsed time and so on.

[0077] In an embodiment of the present invention, the light output signal module outputs a light signal based on the (effective) cumulative distance covered by the simmer. The light signal may output in any one of the variations listed above.

[0078] In another embodiment of the present invention, if the (effective) cumulative distance reaches a predetermined value, such as a total distance milestone, the light output signal module (104) is further configured to output a light signal indicating that such a milestone has been reached. Such milestones may be transmitted from an external device, or may be pre-programmed into the counter current swimming system (100).

[0079] Figure 7 shows a competition tracking method, wherein multiple counter current swimming systems (100), configure be connected in-situ of the swimming pool but may also be connected remotely at separate pools may compare data and output signals to the swimmer.

[0080] In step 71 , the cumulative distance data is transmitted to an external device. The external device may also be another counter current swimming system (100).

[0081] In step 72, the cumulative distance data from another counter current swimming system (100) is received. Steps 71 and 72 therefore describe the process where multiple counter current swimming system (100) may exchange data with one another regarding the progress of the swimmer.

[0082] In step 73, the counter current swimming system (100) compares the received cumulative distance data with its own water flow data.

[0083] In step 74, the counter current swimming system (100) communicates the information regarding the comparison to the swimmer using the lights (31).

[0084] The method of communication to the swimmer may be by outputting light to indicate which swimmer has swam the furthest, the position of the swimmer compared to other swimmers in terms of cumulative distance covered during a predetermined time interval, or even the difference in between the received cumulative distance data, stored cumulative distance data and/or the calculated cumulative distance data.

[0085] Figure 8 shows an embodiment of the present invention where the light output is a function of at least one of the travelled distance or the elapsed time.

[0086] The light output signal module (104) may be configured to output different signals depending on the elapsed time or the elapsed distance.

[0087] In an embodiment, from the start of the exercise to a time ti , the light output signal module (104) may be signal the lights to output green light. From time ti to t2, the light output module may signal the lights to output amber light. From time t2 to the completion of the exercise, the light output signal module (104) may signal the lights to output red light.

[0088] In an embodiment, from the start of the exercise to a distance di, the light output signal module (104) may be signal the lights to output green light. From distance di to d2, the light output module may signal the lights to output amber light. From distance d2 to the completion of the exercise, the light output signal module (104) may signal the lights to output red light. [0089] In an embodiment, from the start of the exercise to a distance di at time ti , the light output signal module (104) may be signal the lights to output green light. From distance di at time ti to d2 at t2, the light output module may signal the lights to output amber light. From distance d2 at time t2 to the completion of the exercise, the light output signal module (104) may signal the lights to output red light.

[0090] In an embodiment, the output of light may be combined with the competition tracking method, such that the performance of the swimmer (S2) may be compared to those of swimmer (S1). In an embodiment, the lights in the pool of swimmer S2 may output the lights showing the progress of swimmer S1 , and vice versa. This allows for the simulation of a competition event even though the two swimmers may be performing at separate pools.

[0091] In the foregoing description of the figures, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the scope of the invention as summarized in the attached claims.

[0092] In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

[0093] In particular, combinations of specific features of various aspects of the invention may be made. An aspect of the invention may be further advantageously enhanced by adding a feature that was described in relation to another aspect of the invention.

[0094] It is to be understood that the invention is limited by the annexed claims and its technical equivalents only. In this document and in its claims, the verb "to comprise" and its conjugations are used in their non-limiting sense to mean that items following the word are included, without excluding items not specifically mentioned. In addition, reference to an element by the indefinite article "a" or "an" does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements. The indefinite article "a" or "an" thus usually means "at least one".

List of elements:

100 system

101 counter current swimming device 102 processing device

103 detector device

104 light output signal module

21 flow distance curve

22 minimum level

23 alternative flow distance curve

30 swimming pool

31 lights

40 light signal generation method

- 41 steady state step

42 milestone detection step

43 milestone signalling step

51 external camera

52 alarm device

70 competition tracking method

71 data transmission step

- 72 data reception step

73 data comparison step

74 display step

81 benchmark time - cumulative distance curve

82 actual time - cumulative distance curve

Claims

1. - A counter current system for a swimming pool, the system comprising a counter current swimming device; a processing device; a detection device, and a light output signal module; wherein the processing device is configured to, during operation of the system: obtain a signal representing a swimmer’s position from the detection device; cause the counter current device to adjust a water output of the counter current swimming device based on the signal; and cause a light output of the lighting device to change based on the signal

2. The system of claim 1 , wherein the detection device comprises a sonar device, preferably located in the counter current swimming device.

3. The system of claim 1 , wherein the detection device comprises a laser device, preferably located in the counter current swimming device.

4. The system of claim 1 , wherein the detection device comprises a portable device worn by the swimmer.

5. The system of claim 1 , wherein the detection device is positioned inside the light output signal module.

6. The system of claim 1 , wherein the detection device comprises a camera.

7. The system of claim 6, wherein the camera is located in the counter current swimming device.

8. The system of claim 6 or 7, wherein the camera is configured to generate images which are processed by a deep learning system for detecting the swimmer.

9. The system according to any one of the preceding claims, wherein the processing device is configured to detect an object in the pool and to raise an alarm in response thereto.

10. The system according to any one of the preceding claims, wherein the processing device calculates an effective cumulative distance swum by the swimmer based on the cumulative flow of the counter current swimming device.

11 . The system according to claim 10, wherein the light output signal module outputs a light signal based on the calculated effective distance.

12. The system according to claim 11 or 12, wherein the light output signal module further outputs a further light signal when the calculated effective cumulative distance reaches a predetermined value.

13. The system according to any one of the claims 10-12, wherein the processing device is further configured to receive a calculated cumulative distance from another system or from memory and calculate a difference between both calculated cumulative distances.

14. The system according to claim 13, wherein the light output signal module further outputs a light signal based on the difference between both calculated cumulative distances.

15. The alarm of claim 9, configured to transmit a first signal when the object, other than the swimmer, enters the counter current swimming pool.

16. The alarm of claim 9 or 15, wherein the first signal is at least one of an audio signal, a visual signal, and a haptic signal.

17. The alarm of claim 9, configured to transmit a second signal when the object, other than the swimmer, is positioned less than a predetermined value from the swimmer’s position.

18. The alarm of claim 9 or 17, wherein the second signal is at least one of an audio signal, a visual signal, and a haptic signal.