PERSONAL SPEED MEASURING EQUIPMENT The present invention relates to speed measuring equipment and is particularly well adapted for measuring the performance of snow skiers or similar. Skiing, like many other sports, may be performed either for pleasure or as a competitive sport. During sporting competitions it is a common practice to measufe at least one parameter to evaluate individual or relative performance. In skiing, for example, it is customary to measure travel time over a preset distance in speed events, or distance covered in jumping events. No-fmally the parameters measured are the easiest to measure under the particular competition conditions. In professional and competitive skiing one of the principal parameters measured and used to evaluate individual performance is time. Although knowledge of time is sufficient to evaluate a competitor's overall performance it dDes not allow the competitor to determine why they did perform as they did and where and how their overall performance could be improved because there is no instantaneous measure of performance. In many competitions speed of travel is the main factor but it is difficult to measure. Difficulties in measuring the speed of e.g. a skier stem from several facts, like the terrain, direction of movement, intermittent contact with the surface, changing body position, changing snow conditions, etc. Some knowledge of speed may be obtained by different methods. In one such method, by knowing the distance covered and measuring elapsed time of the skier over the run. This will result in a speed figure which is the calculated average speed without any indication of the maximum and minimum speed attained or the speed at any particular point or instant. There will be no information about acceleration, deceleration, etc. In a second method instantaneous* speed may be measured at selected points of a given r-uh. ^* This measurement can be performed by using RADAR type

electronic equipment installed somewhere along the run and a spot reading is taken when the skier is judged to be at the proper position. A third method involves quite an extensive use of equipment and personnel whereby the length of the selected run is segmented into relatively short, preferably straight, sections, the length of each section is measured and the elapsed time of the skier through each section is then measured. To obtain the effective speed a series of calculations must be performed but still the result is only a series of speed averages over the various sections.

In all of the above cases the competitor cannot obtain a performance measurement until after the event, by when his recollection of the exact place along the run and his behavior etc may not be quite clear. This partial speed information is, therefore, only of marginal value to the skier. For this reason it is time for a given run which is used as a main guiding factor for the competitor to improve his/her performance. In certain types of competition knowledge of instantaneous speed may be of great help to the competitor in improving overall performance. As an example three specific competitions will be discussed briefly: grand slalom, downhill and jump. In grand slalom the winning competitor has to cover the run in the shortest possible time. The measured time will be a function of the speed with which skier travels through each section of the slalom. This speed is limited by not only the actual snow conditions but also by the length of each straight run and the maximum speed with which the skier enters into each turn without risk of being thrown out of the proper direction of movement. If the competitor knew his instantaneous speed he could adjust it accordingly to maintain optimal speed especially for entering turns and thus to achieve the shortest

possible time.

In downhill run, speed is the most important factor but similarly as in the previous case there will be some sections of the run where speed with which the competitor enters the section may be critical to the success of the run. Knowledge of the instantaneous speed would, therefore, help the competitor to achieve the shortest run time.

In ski jumping the result measured is a distance covered in free flight which is a direct function of the speed with which the competitor left the end of the slope. Since at present there is no knowledge of this speed there is no way for the competitor to- judge the effort made on the slope to attain certain speed to achieve the desired distance.

Any coaching efforts must at present be based on personal observations and in a majority of cases - time measurements. Attention of the instructor or*a coach may be focused on one competitor at a time. Such an arrangement may be satisfactory for the high performance professional skiers but is overly expensive for ordinary skiers who may wish to improve their performance or simply would like to know how they performed in a given run without the necessity of employing numerous personnel and/or equipment. Thus a simple, small and relatively inexpensive speed measuring device for skiers is highly desirable but is currently not available on the market.

All present methods of either time or speed measurement have several major limitations, e-.g. the results of measurements are known to the competitor only after completion of the event, speed measurements are limited to either an average value or instantaneous values at preselected locations. There is no information about the acceleration of the skier, etc. Also many, if not all, methods of time and speed measurement are difficult

or impossible to be employed by a single skier on a personal basis.

According to one broad form the present invention consists of air speed measuring equipment comprising an air speed sensing device providing an output electronically converted into a signal directly interpretable by the user during operation.

Preferably the signal is human speech delivered to the user's ear via a speaker. Preferably measurements and calculated results are stored in a memory device for later processing and/or display.

In a preferred form of the present invention, the air speed sensing device converts the speed of the passing air into a proportional electrical signal. This signal is then processed by a microprocessor according to the program stored in an attached ROM type memory. As a result of this processing a suitable signal is generated which operates a speech circuit to produce a spoken announcement indicating the speed measured. The audio signal can be amplified and applied to two earphones placed closely to the user's ears so that he can hear the announcement. For user comfort the volume of the audio signal can be adjusted by the user to suit individual needs. The announcements are provided at a fixed time interval, the duration of the interval being adjustable by the user to best suit the actual conditions.

After being switched ON the equipment gets into a READY condition and awaits a signal from the user to commence the operation. Such a signal is given by pressing a START button and system operation will continue until a STOP button is pressed. During this time all measurements taken are announced and recorded in the system memory for future processing and/or display. As the whole system is controlled by a microprocessor and is

driven by a crystal controlled clock circuit it is possible to record at least the following parameters of a given run: instantaneous speed, maximum speed, average speed, elapsed time between START and STOP, approximate distance covered. During processing of the accumulated data additional information may be derived, like e.g. acceleration, graphs of speed against time, etc.

For the most consistent results the air speed sensing device is incorporated into a safety helmet which preferably also houses the electronic support equipment. The optimal shape and position of the air duct depends on the shape of the helmet, and is designed to direct the air to the sensor and to be tolerant to a reasonable degree of head movement and to this end one preferred form tends to have a cross-sectional area which increases along the length of the duct towards the sensor.

This method of air speed measurement may incorporate some degree of error due to possible air movement resulting from wind. Theoretically it would be possible to compensate for the air movement (wind) by suitable sensing and signal processing but such would involve' system complications, and increased cost with dubious advantages considering that wind may shift in direction and strength quickly and unpredictably particularly on ski slopes. It has been found during tests that sidewind has relatively insignificant effect on measurement results and, therefore, the lack of this wind correction feature appears to be no real disadvantage.

In a preferred embodiment of the present invention the speed measuring equipment is placed in the safety helmet as often worn by skiing competitors. The air speed sensor is placed in an aerodynamically designed air duct placed on the outside of the helmet while all electronic components are placed in special cavities located on the outside and inside of the safety helmet. The small weight

of the electronic components and supply batteries allows all of the equipment to be placed in the helmet and to be worn by the competitor without any physical strain. The preferred embodiment provides for function buttons to be easily accessible by the user even when wearing protective gloves, it allows the power supply to be switched off for at least 3 days without any loss of accumulated data, it provides spoken information to the user about the condition of the equipment and the supply sources, it also provides means of connecting external PC computer type of equipment for transferring accumulated data for further processing. BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which:

Fig. 1 is a simplified block diagram of the functional components of a single embodiment of the invention; Fig. 2 is a block diagram of the functional components of a preferred embodiment of the invention;

Fig. 3 schematically illustrates a preferred embodiment of the invention located in a safety helmet; Fig. 4 graphically illustrates an example of the printouts resulting from processing in an external PC type computer of stored measurement data; and

Fig. 5 shows a 3/4 frontal view of a safety helmet specially designed to include all parts of the speed measuring equipment. DESCRIPTION OF THE PREFERRED EMBODIMENT

Speed measurement equipment constructed in accordance with one embodiment of the present invention is shown in the diagram of Fig. 1. In this drawing there is an air speed sensing device 10 which responds to the speed of air passing through its aperture in such a way as to produce an electrical signal which is proportional to the

speed of the air. The output signal from the air speed sensor 10 is fed into the signal processing circuit 11 which evaluates the signal magnitude and converts it into a suitable form and composition for use in speech circuit. This composite signal is connected to the speech circuit 12 which when activated will produce a numan speech output signal of sufficient strength to operate earphones 13 which are placed near ears of the user. Operation of the equipment is basically continuous but spoken announcements are produced at a preset interval. The interval between each successive announcement can be altered by the user to suit specific conditions. In'the present embodiment of the invention this interval may be selected to be 1 second or 3 seconds. Fig. 2 shows a block diagram of the functional components of the preferred embodiment. The air speed sensor 110 responds to the speed of air moving through its aperture and produces an electrical signal proportional to the speed of the passing air. Many types of devices may be used as an air speed sensor 110. In the present embodiment of the invention the device used is an air ^* driven miniature turbine which drives a photoelectric shaft position encoder. The output signal from the sensor 110 is applied to the signal processing circuit 111 whose primary function is to convert this signal into digital form suitable for processing by the controlling microprocessor 116. When this initial signal processing is completed the output from the circuit 111 is transferred under control of the microprocessor 116 t,o the speech circuit 112 where an acoustic signal is generated to provide spoken announcements which will convey the value of the measurement being currently taken. The output signal from the speech circuit 112 is applied to the volume control device 113 which allows the user to X, adjust the volume to a comfortable level. After volume

adjusting by device 113 the resultant signal of the spoken announcement is applied to the output amplifier 114 to bring it to the level suitable to drive the pair of earphones 115. Both earphones are placed inside the helmet in positions which place them directly against the user's ears for best audibility of the signal. The described sequence of operation is constantly controlled by the microprocessor 116 which in turn is driven by the clock signal generated in the clock circuit 117. The microprocessor 116 operates under instructions of the software programme which is stored in the nonvolatile ROM memory 118. When the user wishes to start operation of the system the START button 121 is pressed. All functional buttons are connected to the microprocessor via a suitable debouncing and isolating interface 120. The microprocessor receives driving pulses from the clock circuit 117 and in the prescribed time interval, e.g. 1 sec, initiates a reading to be taken from the sensor 110 via the signal processing circuit 111. As soon as the signal processing is completed relevant reading values are stored in the data RAM memory 119 for further processing at any later time. When the spoken announcement is completed the system returns to the condition in which it awaits for the next signal from the microprocessor to take another reading. Readings are taken and stored in the Data Memory until the STOP functional button 121 is pressed. At this moment normal operation of the system is interrupted and it will remain in this state until functional button START 121 is pressed again. This part of the operation of the system resembles that of a stop-watch in which sequential operation of start and stop buttons result in the clock operation being started and stopped and started again, the final display shows the accumulated total. During the time between pressing functional button

START and button STOP the system takes readings and produces spoken announcements of the value measured. However, after depressing functional button STOP 121 the user can read other parameters measured or calculated during the operating time interval, e.g. Maximum measured speed, Average measured speed, Time lapsed between first pressing START button and pressing STOP button, approximate Distance (speed x time) covered between first START and last STOP operation. All those values, if requested by the user, will be read out from the system and provided to the user as a spoken announcement after pressing the functional button READ OUT.

When the user decides that the present run is completed and he/she wishes to commence another run for which separate data should be recorded the functional button RESET 121 is pressed which causes all of the operational registers in the system to be cleared and the whole system is restored to the original conditions before button START was pressed for the first time, and a new run with new data recording may commence. The successful RESET action is confirmed by the system via spoken announcement 'READY' provided to the user. Pressing of the RESET button clears only operational registers, measurement results stored in the Data Memory 119 are unaffected as content of this memory is protected and maintained by the hold over battery for several days, or until the memory is cleared.

When the system is powered up by switching the power supply ON 124 the batteries 125 are connected and the system performs a Power-ON Reset operation whereby all operating registers are cleared and the system is prepared for normal operation. Successful completion of this resetting action is confirmed to the user by a spoken announcement 'READY' . ^* ' The Data Memory 119 has capacity which under normal

operating conditions will store a considerable volume of measurement results. When Data Memory 119 becomes filled in with results and no more space is available the system generates a spoken warning to the user 'MEMORY FULL' and stops accepting any more results for storage. The warning is repeated three times. Once the Data Memory 119 becomes full the system can still be used in the normal manner but without the further results being stored. Under this condition the user should transfer all accumulated data from the Data Memory 119 to an external PC type computer by connecting external equipment to the special data transfer socket 122. Data transfer is initiated by the external computer and upon completion of all data transfer the external computer sends back to the system a suitable signal which will clear Data Memory 119. Data transfer and thus clearing of the Data Memory 119 may be performed at any time, even some time after switching the system OFF as the hold over battery maintains memory content up to several days. If the user does not wish to use measurement recording facility the memory may be disabled by operating the Recording ON-OFF switch 126.

Towards the end of normal operating life of the battery 125 its voltage will drop below a nominal value and the system generates a warning message to the user 'LOW BATTERY', after which the batteries should be replaced to avoid inaccurate operation.

Figs. 3 and 5 illustrate the preferred embodiment of the present invention in a safety helmet. The whole system is divided into several functional units which are placed in the helmet in separate recesses. The safety helmet 130 has a specially designed air duct 135 placed upon it (Ref. Fig. 5) at the end of which an air speed sensor 110 is placed. The whole electronic circuitry 131 is located as one sub unit in a special recess in the

helmet and it is connected via suitable wiring to earphones 132 which are placed inside the helmet. Batteries 133 are placed in a recess similar to the one for the electronic circuitry 131. To equalize weight distribution in the helmet both batteries and electronic circuitry are split into two almost equal parts and placed symmetrically on both sides of the helmet.

Fig. 4 illustrates, as an example, the type of printouts one can obtain after processing of the measurement results recorded during the run and stored in the system memory. It is apparent that the graphs shown are only one possible way of data presentation and many more ways of data processing are possible to best suit the user's needs. The following table shows various switch functions utilised in the device.

FUNCTIONS OF BUTTONS AND SWITCHES

BUTTON NO. 1 (RIGHT SIDE)

START and STOP alternatively, with spoken announcement "START" and "STOP"

BUTTON NO. 2 (LEFT SIDE BOTTOM)

READ OUT causes the recorded values

Of MAXIMUM speed, AVERAGE speed, TIME lapsed and DISTANCE covered to be read and announced

BUTTON NO. 3 (LEFT SIDE TOP)

RESET clears registers (but not DATA MEMORY) in preparations for the next run, it is announced by the message "READY"

POWER SWITCH switches power ON and OFF. When power is switched ON while buttons 2 and 3 are kept pressed - DATA MEMORY is cleared.

AUDIO SOCKET to connect external source of e.g. music

DATA OUT SOCKET to connect external PC type computer for transfer of accumulated measurement results from DATA MEMORY.

Button No. 1 is located on the right hand side of the helmet, towards the lower front part of its side. Button No. 2 is located in the same position but on the left hand side of the helmet, while button No. 3 is placed on the left hand side top of the helmet. The power ON-OFF switch, socket for the external computer connection and socket for external audio program connection are lo'cated at the back of the helmet.

Clearly various designs of safety helmets may be used to accommodate the speed measuring equipment for skiers. In the preferred embodiment of this invention all parts of the speed measuring equipment are placed in the specially designed safety helmet the shape of which has been tested in the wind tunnel for best performance, shape and size, and is shown in Fig. 5. ^ά -

It will be recognised by persons skilled in the'art that numerous variations and modifications may be made to the invention as described above without departing from the spirit or scope of the invention as broadly described.