Patent Application
20050227820
This invention relates to instrumentation and electronic control systems for fitness equipment. In particular, the invention relates to a parameter sensing system for exercise equipment. The parameters can include a user's presence and/or a user's position on an exercise device, and the speed and/or angle of inclination, of an exercise device.
Many types of machines are used for fitness or sport training. Such machines are already known from their wide market availability for domestic, rehabilitation and commercial purposes. Treadmills, or running machines, are one of the most common forms of such machines. Treadmills typically include a support frame, a deck, an endless belt, a drive mechanism and a user interface. The endless belt typically extends over the deck and rotates around the deck and a pair of substantially parallel rollers to simulate the ground moving beneath a user as he or she walks or runs. The user interface associated with recently existing treadmills typically include a digital electronic control system with embedded software routines. Given the increasing functionality offered by digital electronics it is possible for the control system to store programs for different exercise routines, calorie-burning settings, timings, incline settings, speeds, etc. Users of such machines typically step on to the machine, enter their weight, choice of running program, desired speed or incline etc., and then begin to walk or run with the commencement of the belt's motion.
The belt motion typically ceases when the duration of the selected running program comes to an end, or when the user manually stops the belt by actuating one or more pushbuttons on the control panel. In other existing treadmills, a tether is used to releasably connect the user with the control system of the treadmill. The tether, typically a cord, string or cable, is often connected at a first end to the user and at a second end to the control panel of the treadmill. The length of the tether determines the distance the user can move away from the control panel. If the user moves away from the control panel beyond the predetermined distance, the second end of the tether disconnects from the control panel and the belt motion ceases.
Despite their widespread use, such existing treadmills have a number of drawbacks. Many users have difficulty entering their weight and starting the treadmill quickly. The digital electronic control systems with embedded software routines and increased functionality can sometimes be confusing, or even intimidating, for the user to properly use. Such confusion or intimidation caused by the machine's sophisticated user interface often effectively presents a barrier to widespread use, particularly by the elderly or technologically unsophisticated or those user's which may become embarrassed from their perceived ignorance in public fitness clubs or gymnasia.
For various reasons, such as those discussed above, it is often the case that the user does not enter his or her weight accurately. Consequently, the electronic control system is incapable of accurately calculating such useful information as calories burnt or intensity of training during a workout.
Also, particularly in busy fitness clubs and facilities, it is known that some users will step off the machine during their workout to get a drink, for example, but leave the machine's belt in motion. Whilst the first user is away from the machine it is possible for a second user to step on to the machine's moving belt without realising that the belt is moving. Such instances can also present a safety hazard. Although some existing devices incorporate the use of a tether in order to operate the machine, many find the use of tethers to be difficult to use, restricting, uncomfortable, and otherwise undesirable, and, as such, resist using the safety device. Other instrumentation, such as Linearly Variable Differential Transformers (“LVDTs”) or strain gauges, can be incorporated into a treadmill design in order to detect the presence of a user on the treadmill, or to measure the impact of the user's gate as they run or walk on a machine. However, such instrumentation is typically prohibitively expensive, complex, and impractical to deploy on most commercially available machines for mass market use.
Furthermore, many existing treadmills, particularly those configured for home use, fail to provide sufficient safeguards to prevent the undesired use of the machine by children. The inadvertent actuation of the endless belt by a small child can present a safety hazard.
Additionally, typically exercise machines, such as treadmills, require the user to manually enter or adjust controls on the control or display panel of the exercise machine using the user's hands in order to adjust the speed of the exercise machine, such as the speed of the belt on a treadmill. Such manual action of the user's hand(s) and arm(s) is ergonomically awkward and inconvenient for the user.
Also, the monitoring of the speed and incline of exercise machines, such as treadmills, can be difficult due to the repeated loading of the machine by the user and the vibration generated in response to the operation of the machine by a user. Many existing devices used to monitor speed and incline of exercise machines are expensive, and often exhibit poor durability and reliability.
Thus, there is a continuing need for an exercise machine, such as a treadmill, to automatically detect the presence of a user on the machine in a reliable, cost-efficient manner. It would be advantageous to provide an exercise machine, which can automatically measure the weight of the user without requiring the user to navigate and manually enter his or her weight into the control system of the machine. What is also needed is an exercise machine, which quickly and automatically shuts down when the user leaves the machine. There is also a continuing need for an exercise machine that can readily distinguish between a grown user and a small child and adjust its operation accordingly. A need exists for an exercise machine, such as a treadmill, to automatically vary the speed of the machine (such as the speed of the belt of the treadmill) based upon the speed of the user on the machine without requiring the user to manually input a change in speed using his or her hand(s). What is also needed is sensors which can be used to reliably, effectively and cost-efficiently monitor the speed and/or incline of exercise machines, such as treadmills.
According to a principal aspect of the invention, a treadmill includes a frame, a deck assembly, at least one deck deflection sensor, and a control system. The deck assembly is supported by the frame. The deck assembly includes a longitudinally extending deck, at least first and second rollers, and a belt positioned about the deck and the first and second rollers. The deck deflection sensor is coupled to the deck. The deck deflection sensor is a contactless or non-contact displacement sensor including an electrical intermediate device and an aerial. The control system is operably coupled to the at least one deck deflection sensors.
According to another preferred aspect of the invention, a treadmill includes a frame, a deck assembly, at least one deck deflection sensor, a drive assembly, and a control system. The deck assembly is supported by the frame. The deck assembly includes a longitudinally extending deck, at least first and second rollers, and a belt positioned about the deck and the first and second rollers. The deck deflection sensor is coupled to the deck. The deck deflection sensor is configured to produce a signal representative of a weight applied to the deck. The drive assembly is coupled to one or both of the first and second rollers. The control system is operably coupled to the drive assembly and the deck deflection sensor. The control system configured to prevent the treadmill from operating until the signal received from the at least one deck deflection sensor exceeds a predetermined magnitude.
According to another preferred aspect of the invention, a treadmill is configured to detect a user's weight. The treadmill includes a frame, a deck assembly, at least one deck deflection sensor, and a control system. The deck assembly is supported by the frame. The deck assembly includes a longitudinally extending deck, and a belt operably supported by the deck. The deck deflection sensor is coupled to the deck. The deck deflection sensor includes at least one transmit winding, at least one receive winding, and an electrical intermediate device. Wherein the application of the user's weight to the deck assembly causes displacement of the electrical intermediate device, which produces a change in mutual inductance between the transmit and receive windings. The control system is operably coupled to the at least one deck deflection sensor. The control system is configured to electrically measure and correlate the change in mutual inductance between the transmit and receive windings into a deck displacement measurement.
According to another preferred aspect of the invention, a treadmill is configured for operation by a user. The treadmill includes a frame, a deck assembly, at least one aerial, a control system, and first and second electrical intermediate devices. The deck assembly is supported by the frame and includes a longitudinally extending deck, at least first and second rollers, and a belt positioned about the deck and the first and second rollers. The aerial is positioned proximate the deck and includes a set of transmit and receive windings. The control system is operably coupled to the transmit and receive windings. The control system is configured to supply an alternating electrical signal to the transmit windings. The first and second electrical intermediate devices are secured to the right and left legs of the user, respectively. Each intermediate device is configured to produce a variation in the mutual inductance existing between the transmit and receive windings in response to a change in the relative position of the intermediate device to the windings.
According to another preferred aspect of the invention, a treadmill includes a frame, a deck assembly, a drive assembly, at least one aerial and a control system. The deck assembly is supported by the frame and includes a longitudinally extending deck, at least first and second rollers, and a belt positioned about the deck and the first and second rollers. The drive assembly is coupled to one of the first and second rollers. The drive assembly includes a plurality of components configured to rotate about a common axis during use. The aerial is coupled to the frame and positioned adjacent to at least one of the components of the drive assembly. The aerial includes a non-cylindrical arrangement of transmit and receive windings. The control system is operably coupled to the speed sensor. The at least one component of the drive assembly is configured to produce a variation in the mutual inductance of the transmit and receive windings during use as the components moves relative to the aerial. The variation in mutual induction produced by the relative movement of the component to the aerial correlates to the speed of the treadmill.
According to yet another preferred aspect of the invention, a treadmill includes a frame, a deck assembly, at least one aerial, a control system, and an electrical intermediate device. The deck assembly is supported by the frame and has a forward end. The deck assembly includes a longitudinally extending deck, at least first and second rollers, and a belt positioned about the deck and the first and second rollers. The aerial is positioned proximate the forward end of the deck assembly. The aerial includes a set of transmit and receive windings. The lift assembly is coupled to the frame and includes an incline actuator and an actuating arm. The actuating arm is coupled to the forward end of the deck assembly. The control system is operably connected to the lift assembly and to the transmit and receive windings. The control system is configured to supply an alternating electrical signal to the transmit windings. The electrical intermediate device is coupled to the forward end of the deck assembly. The intermediate device is configured to produce a variation in the mutual inductance existing between the transmit and receive windings in response to a change in the relative position of the intermediate device to the windings.
This invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying drawings described herein below, and wherein like reference numerals refer to like parts.
Referring to
The deck assembly 14 includes a deck 32, at least first and second substantially parallel rollers 34 and 36 and an endless belt 38 extending around the first and second rollers 34 and 36 and over the deck 32. The deck 32 is a generally rectangular, longitudinally extending planar structure disposed between the first and second sides 22 and 24 of the frame 12, and adjacent to the first and second rollers 34 and 36. The deck 32 provides a running or walking surface beneath, and supporting, the portion of the belt 38 extending over the upper surface of the deck 32. The deck 32 is formed of a durable, generally resilient material, preferably a high density fiberboard core laminated with a phenolic laminate. Alternatively, the deck can be formed of other materials, such as, for example, plywood, and other fiberboard compositions. The deck 32 is configured to deflect as the user moves and transfers his or her weight to different parts of the deck. For example, if the user is running and plants his or her left foot down at the top left corner of the deck, maximum deflection will occur there and to a lesser extent elsewhere.
The first and second rollers 34 and 36 extend between and rotatably couple to the first and second sides 22 and 24 of the frame 12 at front and rear portions of the frame 12, respectively. The endless belt 38 longitudinally extends along the upper surface of the deck 32 around a portion of the first roller 34, back through the frame 12, and around a portion of the second roller 36 to form a closed endless loop. The width of the belt 38 is preferably generally equal to, or slightly less than, the width of the deck 32. The belt 38 is formed of a resilient, durable material, preferably a multi-weave polyester. Alternatively, the belt can be formed of other materials, such as, for example, other elastomeric materials and other polymers. In an alternative preferred embodiment, the shape of the deck assembly, when viewed along a vertical longitudinal plane, is generally arcuate.
Referring to
Referring to
In a preferred embodiment, the deck deflection sensor 40 includes an electrical intermediate device 42 and an aerial 44. The intermediate device 42 is an indicating element or target, whose displacement alters the electrical inductance between the windings of the aerial 44. Preferably, the intermediate device 42 includes a passive resonant circuit. In a particularly preferred embodiment, the intermediate device 42 comprises a resonant “LC” circuit including an inductance (L) 46 in the form of a coil of conductive tracks or wires, and a capacitor (C) 48, in series. Most preferably, the coil of the inductance 46 is formed as a series of spiralled tracks on a printed circuit board 50 and the capacitor 48 soldered in series with the tracks. The intermediate device 42 is preferably removably connected to the lower surface of the deck 32, and positioned adjacent to the aerial 44, preferably within 0.1 to 100 mm of the aerial 44. Alternatively, the intermediate device 42 can be fixedly secured to the deck, coupled to the deck, or placed directly adjacent to the deck. The sensor is substantially similar to the sensing apparatus described in UK Patent Application No. GB 2374424 filed on Jul. 31, 2002.
The natural frequency (fn) of the intermediate device 42 is calculable by the formula:
Preferably, the LC circuit of the intermediate device 42 has a natural resonant frequency in the range 100 kHz to 10 MHz for good levels of signal coupling without the requirement for expensive, high frequency electronics. Alternatively, the intermediate device 42 can be formed with other natural resonant frequency ranges.
In alternative preferred embodiments, the intermediate device can be a conductive metal target or ferrite slug. An LC resonant circuit is preferred however due to the resultant increased signal amplitude, signal quality factor and signal to noise ratio associated with the LC resonant circuit. In another alternative preferred embodiment, the previously described electrically passive intermediate device 42 can be an electrically active component powered by a power supply such as a battery. Such an electrically active embodiment is preferable if the distance between the intermediate device and the aerial exceeds 100 mm.
The aerial 44 is a sensing unit, which includes an arrangement of transmit windings 52 and receive windings 54. In a preferred embodiment, the aerial 44 is has a generally planar shape. In alternative preferred embodiments, the aerial 44 can be formed in other shapes to suit the specific mechanical geometry of the it's location and, in particular, the location and motion of the intermediate device 42, such as, for example, a cylindrical shape, a curved shape forming part of a cylinder, a hemi-spherical shape and an arcuate shape.
The transmit and receive windings 52 and 54 are preferably formed as tracks on a multi-layer printed circuit board 56. Each aerial 44 preferably has a separate, single intermediate device 42 corresponding to it during operation. Alternatively, two or more intermediate devices 42 of substantially differing resonant frequencies can be used with a single aerial 44. The aerials 44 are operably coupled to the control system 20, and mechanically coupled to the frame 12 at locations adjacent to the intermediate device 42. The aerials 44 can be connected to the frame 12 through mechanical fasteners, adhesives, or other conventional fastening means. The aerial 44 is preferably positioned within 0.1 to 100 mm from the intermediate device 42. In other preferred embodiments the distance between the aerial 44 and the intermediate device 42 can be greater than 100 mm.
Referring to
The receive windings 54 are formed as a simple loop extending along and around the transmit windings 52. The shape of the loop formed by the receive windings 54 is preferably generally rectangular. Alternatively, the shape of the loop can be generally oval, circular, polygonal and irregular. It will be obvious to those skilled in the art that yet other arrangements are also feasible.
The intermediate device 42 is preferably positioned to be substantially parallel to, and within 0.1 to 100 mm of, the transmit and receive windings 52 and 54 of the aerial 44. Alternatively, the intermediate device 42 may move normally to the transmit and receive windings 52 and 54. In such arrangements an alternative sensing algorithm to that previously described is required. For example, an alternative algorithm would be to correlate the variation in received signal amplitude to relative displacement.
Referring to
The frequency generator 60 provides an alternating electrical signal to the transmit windings 52 to produce the local alternating electromagnetic field 58, which is substantially the same frequency as the resonant frequency of the intermediate device 52. The alternating transmit signals energizing the transmit windings 52 are generated using an oscillating circuit source, preferably a 16 or 32 MHz crystal oscillating circuit source, reduced down to suit the resonant frequency of the intermediate device 42, and fed in to the transmit windings 52 via the control system 20. Power sources of other sizes and types can also be used. In particular, referring to
The control system 20, including the set of receive electronics 62 and the micro-controller 64, is preferably also capable of comparing the combined received signals from the receive windings 54, with the voltage and phase of the transmitted signals of the transmit windings 52, such that the variation according to the actual position of the intermediate device 42 can be calculated against a preset or theoretical variation of mutual inductance. The set of receive electronics 62 includes a phase detector 72 and a position calculator 74. The output of the set of receive electronics 62, in particular the output of the position calculator 74, is operably coupled to the microcontroller 64 and the display 66.
The control system 20 is configured to process the signals of the deck deflection sensors 40 and to utilize the deck deflection information in a variety of useful ways. The deck deflection sensor(s) 40 can be used to automatically measure the weight of a user positioned on the deck of the treadmill. The automatic weight calculation eliminates the need for the user to manually enter his or her estimated weight into the control system 20 of the treadmill before commencing operation of the treadmill. The automatic calculation of user weight also eliminates the error associated with the user's estimate of his or her own weight. The user weight information can then be used for calculating information relating to the user's workout or for use in setting other machine parameters such as resistance level.
Additionally, the control system 20 can include a first predetermined deflection or weight setpoint. The control system 20 is then configured to prevent the treadmill 10 from operating unless the weight of the user meet or exceeds the first predetermined setpoint. The first predetermined setpoint can be a fixed value, or a value that can be adjusted as necessary. The first predetermined setpoint is configured to correlate to a minimum weight of a user. Accordingly, the first predetermined setpoint can be set at any predetermined weight value to accomplish the desired inadvertent start prevention feature. In one particularly preferred embodiment, the first predetermined setpoint corresponds to a user weight of 30 pounds. In alternative particularly preferred embodiments, the predetermined setpoint can be set to correspond to other weight settings, such as, for example, 40 pounds, 50 pounds, and 60 pounds. The first predetermined setpoint, therefore, prevents the inadvertent actuation of the machine by a small child, and virtually eliminates the risk of a small child climbing onto a treadmill deck and activating the treadmill.
Further, the control system 20 can include a second predetermined deflection or weight setpoint. The second predetermined setpoint is configured to cease or terminate operation of the treadmill if the weight of the user on the treadmill drops below the second predetermined setpoint for a first predetermined amount of time. The second predetermined setpoint can be set to correspond to a weight below that of a typical user. In one particularly preferred embodiment, the second predetermined setpoint corresponds to a user weight of 70 pounds. In alternative particularly preferred embodiments, the second predetermined setpoint can be set to correspond to other weight settings, such as, for example, 60 pounds, 50 pounds, and 40 pounds.
Alternatively, the second predetermined setpoint can be set as a percentage of the particular user's weight, such as, for example, 80 percent of the user's weight, 70 percent of the user's weight, etc. As an example, if the second predetermined setpoint is set at 70 percent of the user's weight, if a user weighing 200 pounds leaves an operating machine, if the weight on the deck 32 of the treadmill remains less than 140 pounds for the duration of first predetermined time period, the control system 20 will cease the operation of the treadmill 10.
The first predetermined time period can be fixed or adjusted as necessary. In one particularly preferred embodiment, the first predetermined time period is five seconds. In other particularly preferred embodiments, other time periods can be used, such as, for example, 2 seconds, 3 seconds, and 10 seconds. This automatic shutdown feature will automatically shutdown the treadmill 10, in the event the user falls from the treadmill, or leaves the treadmill without shutting the treadmill down. Thus, if the user leaves the treadmill 10 without shutting the treadmill down, the deflection sensors 40 will detect the reduction, or absence of, deck deflection (or user weight) and produce a corresponding signal to the control system 20. If the signal corresponds to a weight that is less than the second predetermined value, and the signal remains for a period of time beyond the first predetermined time period, the control system will automatically shutdown the treadmill 10, or simply stop the movement of the belt 32 of the treadmill 10 and place the controls in a standby mode.
When multiple deck deflection sensors 40 are employed on the deck 32 of the treadmill 10, the control system 20 can be configured to differentiate between the deck deflection sensors 40 and to determine the impact pattern of the user's feet on the deck 32. Such information can be used to adjust the speed or incline of the machine, or to warn the user that user is operating the treadmill at a location too close to either side edge of the belt of the treadmill. Such impact pattern information can also be used to perform stride length calculations and diagnostics.
The number of impacts over a given time can be calculated and compared with the distance travelled by the belt and hence data on stride length or stride pattern compared to the speed and incline of the machine can usefully be generated for diagnosis of the user's performance.
The deck deflection sensors of the present invention enable deck deflection of the treadmill to be measured in an accurate, reliable, a relatively inexpensive and non-complex manner. The deck deflection sensors of the present invention are significantly less expensive than other commonly used instruments, such as, linear differential transformers, ultrasonic sensors, and optical sensors. Because the non-contact deflection sensors of the present invention are not negatively affected by variations in the stand-off distance within 0.1 to 100 mm, the tolerances of the components supporting the intermediate device and aerial of the deflection sensor do not have to be as tightly maintained as required by many existing conventional sensors.
Referring to
The electrical intermediate device 142 is substantially the same as the intermediate device 42. Referring to
The control system 20 can be configured to emit audible warning signals to the user based upon the user's position. The audible signals can be generated directly from the control system 20 or from one or more speakers (not shown), or other sound generating device, mounted in the treadmill. For example, if the user drifts too far to the right of the treadmill during use, the treadmill 10 can emit a first audible warning signal to alert the user to change his or her position. Similarly, if the user drifts too far to the left of the treadmill during use, the treadmill 10 can emit a second audible warning signal. Likewise, if the user is too forward or rearward on the deck the treadmill can emit third and/or fourth audible warning signals to alert the user. The audible warning signals can be specific tones, or specific voice warnings. Such a configuration, would be of particular benefit to blind users who can rely on the audible warning signals to maintain proper position on the treadmill.
Further, in an alternative preferred configuration, the fore and aft positions of the user on the deck 32 can be used to adjust the speed the treadmill 10. The control system 20, which is coupled to the drive assembly 16, can cause the speed to increase if the user is in a forward position on the deck, and decrease if the user is in a rearward position on the deck 32. In yet another configuration, the user's position on the treadmill 10 can be used to automatically control the speed of the treadmill 10. The control system 20 can be configured to increase the speed of the treadmill 10, if the user takes a position toward the right side of the deck 32, or decrease the speed, if the user takes a position toward the left side of the deck 32 during use. This right/left speed adjustment configuration may be more suited for shorter length treadmills.
The aerial 144 and intermediate devices 142 can also be used to enable the user to automatically adjust or control the incline of the deck 32 by varying the user's position on the treadmill 10 during use. Through its connection with the lift assembly 18, the control system 20 can be configured to induce the lift assembly 18 raise the forward portion of the deck 32, or increase the angle of incline of the deck 32, if the user takes a forward position on the deck 32. Conversely, the control system 20 cause the lift assembly 18 to automatically lower the incline of the deck 32, if the user takes a rearward position on the deck 32.
Unlike other existing technologies, such as sonic sensors or IR sensors, which are expensive, and often unreliable, the present invention using inductive position sensing, provides a reliable, cost effective means of automatically controlling or adjusting the operation of a treadmill. Further, the present invention doesn't require additional mounting of equipment onto handrails or displays of the treadmill.
Referring to
In a preferred embodiment, the flywheel 84 includes at least one outwardly projecting constellation 86, and preferably a plurality of constellations 86. The flywheel 84 is positioned adjacent the aerial 244 such that the constellations 86 act as one or more electrical intermediate devices. The rotational movement of the constellations about the aerial 244 causes a variation in the mutual inductance of the transmit and receive windings 252 and 254 of the aerial 244. The control system 20 monitors this variation of mutual inductance to determine the rotational speed of the flywheel 84 and the shaft 82. In alternative preferred embodiments, the aerial can be positioned to other rotational members of the treadmill including the rotor of the motor, the output shaft, or one of the rollers. Further, the electrical intermediate device can be other conductive metal targets, a ferrite slug, a resonant LC circuit, or an electrically active component powered by a battery. The contactless configuration of this speed sensing aerial provides a low cost, reliably and accurate means of monitoring the speed of the treadmill without producing undesirable drag or resistance on the drive assembly.
Referring to
An electrical indicating device 342 is coupled to the forward end 90. Like the intermediate device 42, the intermediate device 342 causes the mutual inductance between the transmit and receive windings to vary in relation to the location of the intermediate device 342 relative to the frame 12. The control system 20 monitors the mutual inductance from the windings of the aerial 344 to identify the position of the forward end 90 of the deck assembly 14. Based upon these signals, or variations in the mutual inductance, the control system 20 can determine the incline of the deck assembly 14.
The control system 20 can be configured with a single micro-controller 64 (or microprocessor), a single frequency generator 60, a single set of receive electronics 62 for processing the signals or variation in inductance in the winding of one, two or all of the aerials 44, 144, 244 and 344 of the treadmill 10. Alternatively, each aerial 44, 144, 244 or 344, or group of 2 or more aerials, can have its own dedicated micro-controller or microprocessor, or any combination of one or more frequency generators, sets of receive electronics, micro-controllers, and displays.
While the preferred embodiments of the present invention have been described and illustrated, numerous departures therefrom can be contemplated by persons skilled in the art. For example, in an alternative preferred embodiment, the deck deflection sensor can be configured without an electrical intermediate device, and the transmit and receive windings can be positioned on two separate bodies. In this configuration separate electrical connections are required for each of the transmit and receive windings. Therefore, the present invention is not limited to the foregoing description but only by the scope and spirit of the appended claims.
