GB2176036A - Counting device for use by swimmers - Google Patents

Abstract

A device for use by swimmers in assessing performance is secured to a swimmer's body. The device incorporates sensing means for sensing the execution of successive strokes, and means for counting the number of successive strokes executed. The sensing means may be sensitive to the orientation of the force of gravity relative to the device, whereby the execution of successive strokes may be determined by changes in the orientation with respect to the vertical part of the swimmer's body, to which the device is attached, during each stroke, or may be sensitive to accelerational or decelerational forces arising from the movements of the device, and the part of the swimmer's body to which the device is attached. The number of lengths of a pool swum may also be counted.

Description

SPECIFICATION Device for use by swimmers This invention relates to a device for ue by swimmers in assessing their performance, for example in keeping an account of the number of lengths of the pool swum of the number of strokes made.

According to the invention there is provided a device for use by swimmers in assessing performance, the device being adopted to be secured to a swimmer's body and incorporating sensing means for sensing movements made by the swimmer in swimming and thereby detecting the execution of successive strokes, and means for counting the number of successive strokes executed.

The sensing means may be sensitive to the orientation of the force of gravity relative to the device, whereby the execution of successive strokes may be determined by changes in the orientation with respect to the vertical part of the swimmer's body to which the device is attached, during each stroke.

Alternatively, or in addition, the sensing means may be sensitive to accelerational or decelerational forces arising from the movements of the device, and the part of the swimmer's body to which the device is attached.

In a preferred embodiment, the device is in the form of a small unit provided with a strap whereby it can be attached to one of a swimmer's limbs, or with a suitable clip whereby the device may be attached to a swimming costume.

The device may be an electronic device with a self-contained power supply, a display, and input means, for example in the form of a manually operable push button or buttons, whereby the device may be operated in different modes and/or data may be entered into the device, as set out in detail below, the whole being, or course, appropriate waterproofed. The device preferably has the outword form of a wrist-watch and has a time-piece function so that it may be used as a watch in everyday use.

In its preferred forms, the device incoporates sensing means, for sensing when successive swimming strokes have been executed, timing means, manually operable input means, processing means arranged to receive signals from the sensing means, timing means and input means, and a display driven by the processing means. the display may be a digital electronic display, for example on LCD display, of the kind commonly used in digital electronic watches.

In its preferred form, the sensing means includes a two sensors, a first one of which is sensitive to the orientation of the force of gravity relative to the device and the second of which is sensitive, for example, to accelerational or decelerational forces.

The first sensor may be utilised, for example, for strokes in which the arms of the swimmer move in a manner which approximates roughly to rotation about a horizontal axis, for example the freestyle of crawl stroke. The second sensor may be utilised for storkes in which the inclination of the swimmers limbs relative to the vertical may vary in a less pronounced manner, for example the breast stroke.

The first sensor, in this instance, may comprise, for example, a small weight, such as a metal ball, guided for free movement between limiting positions, in one of which the weight operates a detector to provide a signal, so that each time the weight moves to said one limiting position a respective signal is produced. The weight may comprise, for example, a pivotally mounted weight, a metal ball confined within a tube or the like arrangement. Thus, assuming the device to be attached to the swimmer's wrist, for every stroke which the respective arm completes, the weight will be moved to said one limiting position at least once during every stroke to operate the detector and produce a respective signal.

The second sensor, sensitive to acceleration or deceleration of forces, may likewise comprise a weight mounted for movement between the limiting positions, but in this instance urged towards a predetermined position by a spring or the like so that only when the device is subjected to acceleration or deceleration can be weight be moved from its normal position to operate a detector. Alternatively, the first and secnd sensors may be constructed virtually without moving parts, for example being constructed as an electronic load-sensing device such as a piezo-electric cell, strain gauge or the like with a small weight mounted thereon.

Provision may be made wereby the swimmer can select, by operation of said input means, which of the two sensors is effective to determine when a stroke has been executed. However, it will be appreciated that it is possible for both sensors to remain effective whenever the device is in use and for the device to incorporate processing means whereby the signals produced by the two sensors and the variations of these signals with time, and the inter-relationship of these signals to one another canbe analysed, to provide a reliable detection of the execution of a stroke.For example, the arrangement may be such that the device may be placed by operation of the input means, in a calibrating state in which the substantially repeating cycle of signals produced by the sensors during the execution of repeated strokes in swimming in a particular style is recorded, whereafter the device may be set in a normal state in which repetition of each cycle of the corresponding sequence will be interpreted by the processing means as the detection of the execution of a respective complete stroke.

Other means of detection may be utilised, of course. for example the device may incorporate a light sensor, a sensor of the dielectric constant of the medium around the device, a pressure sensor or the like whereby fluctuation in these quantities during swimming, e.g. as a swimmer's arms are withdrawn from and returned to the water, will provide a detection of the execution of a stroke.

Where the sensors operate substantially by sensing accelerational or decelerational of forces, they may be so contrived as to be capable of detecting the slight impact produced by the swimmer's limbs breaking the water surface. Likewise such sensors may be arranged to detectthe somewhat sharper impact which may be produced either deliverately or as a matter of course by the swimmer striking the end ofthe pool atthe completion of a length, with the device being arranged to count individual lengths swum instead of, or in addition to, individual strokes executed.

The device, using signals from the timing means and from the sensors, is able to calculate time related quantities such as strokes rate, elapsed time, etc., as will be apparent from the examples given below.

As will be apparentfrom the above and what follows, several of the preferred modes of operation of the device require the provision, to the processing means, of informtion not availablefrom the sensing means or the timing means. Such information is preferably carried in the device in digital formin an electronic memory, and by appropriate operation of the input means (push buttons or the like) the device may be placed in a selected one of a series of calibrating states in each of which a respective quantity may be entered in the appropriate area in the memory.The calibration system adopted may be similarto that utilised in time setting in digital electronic watches, with the display indicating a number advanced automatically so that the desired number can be entered simply by pressing or releasing a button when the desired number is shown on the display, with the display also provid ing an indication of what quantity is currently under calibration.

By way of non-limiting examlple, the device may be capable of operating in any one of the following modes: a) on the basis of a pool length entered via the calibration facility, to calculate and display strokes per metre or yard, (on the basis of the stroke count occurring in the time lapsing between successive signals provided when the swimmer leaves one end of the pool and when he reaches the other end of the pool).

b) stroke rate (strokes executed per unit of time or time per given num ber of strokes) c)overall elapsed time (e.g. between signals pro vided by-the swimmer leaving one end of the pool and on reaching the opposite end).

d) given a predetermined number of lengths entered via a calibration facility, to indicate the overall time required to complete the number of lengths entered (on the basis of signals provided at the comlpletion of each length) e) to operate an audible alarm at a pre-set time after a starting signal, whereby a swimmer can set, forexamlple, atargettimefora given distance and will be advised, by triggering of the alarm, as to whether or not, and by what amount, he has-failed to reach the target set.

f) on the basis of a given distance covered per stroke executed, (or, for example, per hundred strokes executed), entered in the device using the calibrating facility, to calculate and display the total distance swum, based upon the number of strokes executed. Thus, the device may provide an indica tion of distance swum, for example as might be particularly useful in swimming in the open sea.

g) to operate as a stop watch h) to operate as a normal time-piece to indicate time of day.

The device may incorporate further sensing means, for example means for sensing physiological quantities such as the heart rate of the wearer,and may have a facility for calculating and displaying, on the basis of pre-set information,as well as the total strokes or lengths swum etc., the total number of calories used in a swimming session. The device may also include means for sensing the temperature of the environment in which the device is located, i.e.

the temperature of the water during swimming or, where the device is worn as a normal watch at other times,the temperature of the surroundings. The device may also include a water pressure sensor, with the device, in a further mode, being arranged to give readings of depth under the water surface. Such a pressure sensor may also form the basis of the means used for sensing execution of successive strokes in swimming.

Where an alarm facility is provided, the device in one mode, may operate the alarm when a pre-set number of strokes, or a pre-set number of lengths have been swum. The alarm may also be used as an ordinary alarm when the device is used as a conventional timepiece.

Claims (5)

1. A device for use by swimmers in assessing performance, the device being adapted to be secured to a swimmer's body and incorporating sensing means for sensing movements made by the swimmer in swimming and thereby detecting the execution of successive strokes, and means for counting the number of successive strokes executed.

2. A device according to claim 1 wherein said sensing means is sensitive to the orientation of the force of gravity relative to the device, whereby the execution- of successive strokes may be determined by changes in the orientation with respect to the vertical part of the swimmer's body to which the device is attached, during each stroke.

3. a device according to claim 1-, wherein said sensing means is sensitive to accelerational or deceierational forces arising from the movements of the device, andthe part of the swimmer's body to which the device is attached.

4. A device for use by swimmers in assessing performance,the.device being adapted to be secured to a swimmer's body and incorporating detecting means for detecting the execution of successive strokes, and means for counting-the number of successive strokes executed.

5. Any novel feature or combination of features described herein.