USER DETECTION FOR EXERCISE EQUIPMENT
Embodiments of the present disclosure include a user detection system for exercise equipment, such as a treadmill. In an embodiment, a sensor monitors displacement between a deck supporting a moveable treadmill belt and aspects of a treadmill frame. As users interact with the treadmill, a processor uses a sensor signal indicative of the displacement to determine whether a user has mounted the treadmill belt.
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1. Field of the Invention
Aspects of the present disclosure relate to the field of exercise machines. More specifically, the invention relates to exercise machines having user detection features.
2. Description of the Related Art
Commercially available residential and industrial exercise machines are popular with many individuals who want to enjoy cardiovascular exercise to lose weight, obtain or maintain fitness, and the like. Treadmills are one example, and nearly all treadmills have a kill function designed to stop the machine in an emergency situation, often implemented through a user tether or user accessible button. However, there remains a need to be able to detect the presence or absence of a user. Some manufacturers employ an infrared emitter and detector. Often the emitter emits radiation aimed at the approximate location of a user's chest, and the detector detects reflected radiation when a user is present. However, such a system can include inaccuracies. For example, lighting conditions where the machine is located may saturate or confuse the detector; the color and material of a user's clothes may similarly confuse the detector or the like.
Manufacturers also introduced detection devices that identify the presence of a user based on changes in load on the electric motor driving the belt of a treadmill. Each time a user plants a foot, the weight of the user supplies an additional load on the belt, and thus the motor, compared to when no user is present. There are limitations to such a solution, however, including the need for the belt to be moving. Moreover, as the incline of a treadmill increases, there is less or no load change to detect, which will generally affect the accuracy of the user detection.SUMMARY
Accurate and consistent user detection with exercise equipment is important for a variety of reasons. For example, it is advantageous to be able to stop a machine in an emergency situation, such as if a user falls off the machine, cannot reach a kill switch mechanism, the user leaves a machine running, or the like. A particularly problematic issue occurs when a user wants to rest, stretch or otherwise stop exercising for a short time but leaves the belt running at speed. In such situations, it is advantageous to alert the user to reengage or halt the belt movement. Additionally, an accurate detection of force and/or cadence of a user's footfalls on a treadmill can help diagnose and correct running or walking form issues, such as to help prevent or reduce injuries or to train or retrain a person to walk. Such a system can also help control workouts, aid in rehabilitation settings, and the like.
An embodiment of this disclosure provides a user detection system for an exercise machine including one or more sensors that detect vertical and/or horizontal movement in a treadmill deck with respect to a treadmill frame. An example of this type of sensor includes a reluctance-type sensor comprising a magnet and induction coil to detect induced current based on the movements of a treadmill deck with respect to the treadmill frame caused by the movements of a user. More specifically, in an embodiment, a treadmill comprises a stationary frame supporting a floating deck beneath a treadmill belt. The deck may rest on, for example, flexible rubber rails or the like attached to the frame or the like that allow some cushion and shock absorption for a user. The deck further includes a magnet operably affixed to move as the deck moves it and an induction coil operably affixed on at least one frame rail in close proximity to the magnet, together forming a reluctance sensor. As a user walks, runs, or even simply shifts his or her weight on the treadmill, the user will change weight on the deck, causing the flexible rubber rails to flex. The deck will thereby shift in relation to the frame, and therefore the magnet will move in relation to the induction coil, which may be operably stationary with the frame, thereby inducing a current/voltage in the coil that can be measured, and providing an indication of the presence of the user.
In an embodiment, these signals can be used to pause or stop a treadmill, for example, when a user departs without stopping the belt of the treadmill. These signals can also be used to power down a machine after a user has been gone for a certain period of time. In yet another embodiment, the user detection can be used to alter a display to include indicia designed to attract the attention of a potential user when there is no user at the machine; for example, the attract screens may include a challenge screen (such as displaying a message such as “Can you improve your mile time?” or “How far can you go today?”) or a welcome screen. Additionally, the treadmill can initiate a program start sequence when a user is detected.
Moreover, in an embodiment, two or more of these sensor sets may be placed near opposite rails of a treadmill frame. The various readings from the multiple sensors can be compared to determine left footfalls versus right footfalls, cadence, impact variance between a user's legs and the like. Information that can be derived from the multiple sensors, in an embodiment, may be used to determine if a user is favoring one leg or the other, differences in stride or gait, and the like. In turn this information can be evaluated to provide technique suggestions, training tips, and so on.
A general architecture that implements the various features of the disclosure will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the disclosure and not to limit its scope. Throughout the drawings, reference numbers are reused to indicate correspondence between referenced elements.
As stated the detection of a user's presence on exercise equipment can provide a number of benefits, including safety, power savings, motivation, training, and the like. A user detection system for exercise equipment, such as a treadmill will now be described with reference to the figures.
Although the treadmill 100 of
As illustrated in
With embodiments of the arrangement and make-up of user detection sensors described, it is helpful to understand the operation of such a sensor.
In an embodiment, the sensors include a user detect sensor, such as the magnet and coil 214 disclosed herein, other magnetic sensors, optical sensors, or the like. In an embodiment, a motor/incline control board 528 includes an incline controller 526, a speed sensor 527, and a motor driver 529. In an embodiment, the incline controller 526 provides indications of the current incline, as well as controls raising and lowering of the treadmill belt. In another embodiment, the incline controller functions may be handled by multiple components. One of skill in the art will recognize from the disclosure herein a wide variety of sensors and motor feedback systems capable of monitoring the incline and speed of a treadmill 100, including for example, induction sensors, optical sensors, potentiometers, and the like. In some embodiments, the speed sensor 528 may include a reluctance sensor similar to the user detect magnet 212 and inductance coil 214, where, for example, one or more magnets rotate operably with a driving motor to pass a stationary inductance coil. Those of skill in the art will understand that other sensor elements may also be used. For example, one or more metal components could rotate operably with a driving motor to pass a stationary magnet/sensor combination. The metal's interaction with the magnet can generate a readable signal.
The signal processors may include a translator board 518, a FIT (fitness) processor 520, and a display processor 522. In an embodiment, the translator processor board 518 comprises one or more circuits and/or microprocessors that, among other things, may condition signals and supply motor feedback functions. In the illustrated embodiment, the translator board receives feedback from the incline sensor 526 and can send commands to an incline motor to raise or lower the treadmill's incline. Similarly, the speed sensor 528 provides an indication of the treadmill belt speed to translator board 518, and the translator board can send commands to a treadmill belt drive to increase or decrease the speed as necessary. In addition, translator board 518 may receive instructions from other components or supply various data thereto.
In an embodiment, the FIT processor 520 manages workout programs. This management may include duration, speed, intensity, incline, and segment length parameters, for example. Workout programs may include specific duration, distance, incline, and/or intensity parameters and the like, creating, for example, timed workouts, user controlled workouts, specific distance workouts, hill climbing workouts, interval workouts, fat burning or heart rate controlling workouts, or the like. The FIT processor 520 may also process or store information relating to heart rate, calories burned estimates, and the like. In an embodiment, the display processor 522 governs a display and/or its controls, such as an interactive display. The display processor 522 includes, in various embodiments, fan controls, a television interface, a display interface, an iPod® or other music, multimedia, or other player interface, or the like. In an embodiment, the display 524 includes an LCD screen, an interactive touch screen, a plasma display panel, LEDs, indicator lights, or the like. As illustrated, translator board 518, FIT processor 520, and display processor 522 may be one or more physically separate processors and/or electronics boards, or one ore more can be combined within signal processor 519.
In the illustrated embodiment, the user detection inductance coil 214 communicates with the translator board 518. The translator board 518 interprets the signals from the inductance coil 214 and forwards them to the FIT processor 520. The FIT processor 520, in an embodiment, may use this indication to help control a workout program. For example, the FIT processor 520 may use the absence of a user to affect a workout program. The FIT processor communicates a signal to the translator board 518, which in turn communicates signals that cause, for example, a treadmill belt drive to slow the treadmill belt and the incline motor to lower the incline. In an embodiment, FIT processor 520 may communicate a user presence parameter to the display processor 522, which may command the display 524 to display indications of the presence or absence of a user. Some exemplary applications of the user detection indications are discussed below in more detail with relation to
In an embodiment, microcontroller 639 includes an analog-to-digital converter 636 and a digital filter 638. The passive low pass filter 634 smoothes the signal to help remove anomalies in the signal and provide the overall long-term trend of the signal. The analog-to-digital converter 636 allows the signal to be translated into a digital format to aid more accurate and precise filtering and manipulation. The digital filter performs mathematical operations on the sampling, discrete-time signal to create an output indicative of, among other potential information, the presence or absence of a user.
In an embodiment, the translator board 518 ignores any DC offset caused by the amplifier circuits and interprets a peak-to-peak amplitude of the inductance coil 214 signals. If the peak-to-peak value determined in the microcontroller 518 is greater than a specific threshold, then a user is determined to be present. In an embodiment, the threshold value may be based on a speed-dependent calibration of the inductance coil 214 readings without a user present to automatically set the threshold. In an embodiment, the translator board 518 may interpret the user detection signals to provide only periodic or intermittent data to the FIT processor, such as, for example, every 0.5 seconds or every 0.25 seconds. Additionally, or in the alternative, the translator board may incorporate an interrupt from the sensor. Any interrupt is preferably in a range from about zero to about two seconds. In an embodiment, the interrupts are faster than two second intervals to aid in rendering more accurate readings. While the user detect sensor can function at longer intervals, safety features implemented with the user detection may have reduced effectiveness. Similarly, more advanced uses of the signals (see
In an embodiment, the sensor 214 produces a signal as the magnetic field changes with respect to a coil. Therefore, the expected characteristics of the signal may include a pulse train-like signal cycling within the normal expected cadence of a person walking, jogging, running or sprinting. Signal characteristics above and below those thresholds may advantageously be interpreted as noise. Thus, in an embodiment including the foregoing expected pulse train signal, the discussed circuitry conditions the signal for further processing by the microcontroller 639 by filtering the signal to within expected cycles and applying some gain.
Accordingly, the signal from the sensor 214 is communicated to the conditioning circuit at connector 702 for conditioning. The circuitry employs the capacitor 703 to filter common noise producers, such as, for example, a power supply (60 Hz in the U.S., often 50 Hz elsewhere), although other filters may be used. The circuitry employs a safety resistor to protect against, for example, electrostatic discharge or power spikes and employs the one or more optional gain and filter stages 706, 708 to further amplify and condition the signal. In an embodiment, the gain and filter stage 708 sufficiently amplifies and filters the signal from the sensor 214 that the second stage 706 is not used. The circuitry then employs the capacitor 710 as an anti-aliasing low pass filter before the signal is output from the conditioning circuit and communicated to the microcontroller 639.
Now, with reference to
In another embodiment, the routine may be one or more threads of a processor (such as FIT processor 520) that loops from block 864 or the NO condition of block 856 back to the user detect block 850 rather than utilizing interrupts. In such a case, the FIT processor may well manage the break and resumption of the thread. Such an alternative method may also utilize a system clock or other timing metric to implement the time delay rather than one or more counters. This may allow more accurate time delays based on the threading as the processing of the user detect thread may not be uniform if other threads must also be processed at various times.
For example, this process could be used to determine that a user's stride is too long and to output a message to shorten the stride for a given speed. The process could also determine if one leg is favored over another to help diagnose or even prevent possible injuries. In another example, the system could detect whether a runner is landing too flat-footed or running well on the balls of their feet and provide tips on how to alter this. In an embodiment, a workout program may be customized based on some or all of this information. For example, the workout may be slowed for a brief period to help a user feel a recommended change in stride before building back to a quicker pace. Similarly, if the interpreted data indicates that a user's technique deteriorates when an incline is too steep, the FIT processor 520 may send a command to the incline motor 526 (through translator board 518) to lower the incline until the user's technique recovers.
The foregoing processes 800, 900, 1006 are just a few examples of the types of uses for the user detection systems described herein. In another embodiment, the duration and amount of impact could be monitored for additional safety or exercise form considerations. For example, if a user collapsed on the treadmill and was not using a kill switch tether or could not reach a stop button, the user detection system could determine that an impact was different from normal step impacts (for example, a much longer duration) and trigger an emergency stop of the treadmill belt to help reduce burns, scrapes, or other injury that could result from a still moving treadmill belt.
Moreover, the methods illustrated above indicate that exercise equipment may present information to a user through a display. It is understood that messages for a user could be messages displayed on a screen, indicator lights, or the like. Messages could also be audible tones, beeps, synthesized or recorded voice messages, or the like output through a speaker. Messages and user presence or footfall data can also be output to a computer or saved in memory for later access, additional processing and evaluation, analysis of user trending over time, and the like.
Many trainers and exercise equipment manufacturers believe that user form should seek to minimize footfall force so as to reduce strain on joints, muscles, and the like. A lighter force for a footfall is likely to register as a smaller signal from a user detection sensor with a longer duration, while a heavier force will likely be indicated by a stronger signal over a shorter amount of time, in an embodiment based on the vibrations caused by the user's impact on the treadmill belt.
In an embodiment, a force footfall graph 1186 provides indications such as “Ideal,” “Moderate,” and “Heavy.” In an embodiment, the force graph 1186 may include one or more indications of force, such as increased bar length of the graph, color changes, and the like for heavier footfall forces. Similarly, a user's cadence—generally expressed as steps per minute—can be measured based on the detection of each impact over a period of time. Many trainers and exercise equipment manufacturers believe that proper running form should include approximately 80-90 steps per minute. Form feedback display may thus include a cadence rate display 1188. Such a cadence rate display 1188 can help avoid strides that are too long, too short, aperiodic, or the like and may provide teaching instruction for a user to attain a more efficient form.
One of skill in the art will understand that there are many ways to display one or more program information panels 1192 and one or more form feedback panels 1184. For example, one or more LED fields can be used, a single LCD display may be partitioned to show different exercise program and form information, and the like. A limited number of such displays can cycle program and/or form feedback information with a limited number of displays, and the like. Similarly one of skill in the art will understand that there are many input options for various embodiments, which can include control buttons 1190, touch screens, dials, switches, a microphone for voice recognition, and/or the like. One of skill will also understand that various running parameters, such as footfall force and cadence, can be adjusted to conform to current industry understanding of proper technique. For example, in an embodiment, a treadmill manufacturer, owner, operator, or the like can upgrade the programming of a FIT processor 520 to alter parameter limits.
The human analog display 1296 may mimic this bouncing motion when user detection indicates heavier than ideal footfall forces and provide text or other illustration on how to minimize this bounce. Similarly, the display may illustrate other technique tips. For example, an embodiment of a treadmill with multiple user detection sensors may provide indications if a user is likely bouncing from side to side or the like. Such a human analog display 1296 may incorporate an avatar within a virtual world, as described below.
Yet another use for user detection features as described herein is to provide input for program interactions in some embodiments. For example, in an embodiment with multiple user detection sensors, a FIT processor 520 may drive a workout program that includes a virtual realty aspect, such as a graphical world provided to a display 524. Such a graphical world can help entertain a user during his or her workout. At various times within a workout, the user may have the option of altering the program, changing a virtual path within the graphical world, and/or the like. In an embodiment, a user may stomp harder with his or her left or right foot to select among the options. For example, the display 524 may show a forested path so that it appears that a user is running along it. At some point, the path may branch to the left and right, such as with an indication that going left will be a mountain path and right will be a path along a river. In the example, the user may stomp with his or her left foot to choose the mountain path or stomp with his or her right foot to choose the river path, and the FIT processor 520 can adjust the display 524 accordingly. In an embodiment, this user input may also—or alternatively—drive an effect within the user's workout. For example, choosing a mountain path may also increase the treadmill's incline as if the user was actually climbing a mountain. Other input determinations may also be possible apart from a “stomp.” For example, the user may favor stepping closer to a left edge or a right edge of the treadmill belt to signal making a left or right decision. In such a case, signal strengths from multiple user detection sensors of steps could be compared against average signal strengths of a user stepping in a central location. If the user favors the left side of the treadmill for a few steps, in an embodiment, a left side user detection sensor will likely generate greater than average signal strengths, while a right side user detection sensor will likely generate lower than average signal strengths. One of skill in the art will understand many other potential uses of the user detection as an input device apart from those illustrated as examples herein.
Although the foregoing has been described in terms of certain specific embodiments, other embodiments will be apparent to those of ordinary skill in the art from the disclosure herein. Moreover, the described embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. Additional uses for the user detection system are possible, including equipment diagnostics. For example, a treadmill's motor and/or rollers could cause detectable vibration in the sensor over normal operating parameters if the treadmill becomes unbalanced or any of the parts are out of alignment. The user detection sensor, such as magnet 212 and inductance coil 214, can detect these vibrations to help in diagnosing repair issues. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms without departing from the spirit thereof. Accordingly, other combinations, omissions, substitutions, and modifications will be apparent to persons of skill in the art in view of the disclosure herein. Thus, the present disclosure is not limited by the preferred embodiments, but is defined by reference to the appended claims. The accompanying claims and their equivalents are intended to cover forms or modifications as would fall within the scope and spirit of the disclosure.
19. A method of operating a treadmill to determine when a moving belt likely does not include a user of the treadmill, the method comprising:
- receiving in a processor a signal indicative of a displacement sensor detecting displacement of (i) a first treadmill member movable when said user loads at least a portion of their weight on a treadmill belt, with respect to (ii) a second treadmill member substantially unmovable when said user loads said belt;
- electronically determining whether the signal likely represents that said user is present; and
- when said determining indicates said user is not present, electronically altering operation of said treadmill.
20. The method of claim 19 comprising:
- receiving in a coil a change in a magnetic field when said first member moves with respect to said second member; and
- outputting said signal based on said change in said magnetic field.
21. The method of claim 19 wherein the altering step comprises displaying a message to a user.
22. The method of claim 21 wherein the message comprises a countdown to a slowdown of the belt.
23. The method of claim 21 wherein the message comprises a request for the user to return.
24. The method of claim 19 wherein the altering step comprises a slowdown of the belt.
25. The method of claim 19 wherein the altering step comprises an emergency shutdown.
26. The method of claim 19 wherein the altering step comprises adjusting an exercise program.
27. The method of claim 26 wherein the altering step comprises adjusting at least one exercise parameter.
28. The method of claim 27 wherein the altering step comprises adjusting one or more of: speed limits or incline limits.
29. A treadmill configured to determine when a moving belt likely does not include a user, the treadmill comprising:
- a treadmill belt;
- a first treadmill member movable when said user loads at least a portion of their weight on said treadmill belt;
- a second treadmill member substantially unmovable when said user loads said belt;
- one or more processors configured to receive a signal indicative of a displacement sensor detecting displacement of (i) said first treadmill member, with respect to (ii) said second treadmill member, said processors configured to electronically determining whether the signal likely represents that said user is present; and when said determining indicates said user is not present, configured to electronically altering operation of said treadmill.
30. The treadmill of claim 29 comprising a coil configured to receive a change in a magnetic field when said first member moves with respect to said second member, wherein said one or more processors are configured to output said signal based on said change in said magnetic field.
31. The treadmill of claim 29 wherein said one or more processors are configured to display a message to a user.
32. The treadmill of claim 31 wherein the message comprises a countdown to a slowdown of the belt.
33. The treadmill of claim 31 wherein the message comprises a request for the user to return.
34. The treadmill of claim 29 wherein said one or more processors are configured to slowdown the belt.
35. The treadmill of claim 29 wherein said one or more processors are configured to perform an emergency shutdown.
36. The treadmill of claim 29 wherein said one or more processors are configured to adjust an exercise program.
37. The treadmill of claim 36 wherein said one or more processors are configured to adjust least one exercise parameter.
38. The treadmill of claim 37 wherein said adjustment comprises one or more of: speed limits or incline limits.
Filed: Dec 19, 2008
Publication Date: Jun 24, 2010
Applicant: Unisen, Inc., dba Star Trac (Irvine, CA)
Inventors: David Wayne Morris (Anaheim, CA), Kevin Corbalis (Tustin, CA), Gregory Allen Wallace (Mission Viejo, CA), Shatish Mistry (Irvine, CA)
Application Number: 12/340,470
International Classification: A63B 24/00 (20060101);