Patent Application
20240042263
The invention relates to monitoring physical exercise, and in particular, to monitoring a physical exercise performed in a weight exercise device.
There are a large variety of devices for physical exercise. These devices allow exercises to be performed in controlled, consistent, repeatable manner. However, conventional exercise devices typically lack the ability of monitoring and recording the quality and progress of the exercise. One convention way of keeping track of the progress is the use of a pencil and a paper. However, this may be tedious and error-prone and requires the user to carry pencil and paper along. It may be very difficult for users of exercise devices to monitor their own performance during the exercise.
In order to alleviate these problems, various approaches have been presented. Many of these approaches involve implementing smart functionalities to the exercise devices themselves. Exercise devices may be provided measurement sensors and computing devices that produce information for the users on their exercises, for example. However, each manufacturer of a smart exercise device tend to use their own approach for measuring and presenting data, and thus, the information received by the user is often poorly combinable between devices of different manufacturers. In addition, manufacturing and maintenance costs of a smart exercise device is typically significantly higher than the costs of a conventional exercise device.
Another approach is to bring monitoring capabilities to a conventional exercise device in the form of an addon measurement device. For example, many of exercise devices include a weight stack arrangement with which a user can choose the total weight used during the exercise. A measuring device may be configured such that it can be inserted to the selector hole of the weight plate instead of a conventional selector pin. The measuring device can determine an estimate of the chosen total weight based on mechanical stress on the measuring device caused by the selected weight plates. However, even with this approach, it may be difficult to achieve consistent measurements in different weight stack arrangements of different types of exercise devices. Further, weight stack arrangements manufactured by different manufacturers may have different dimensions and tolerances for said dimensions. As a result, obtaining consistent, reliable measurement results from different exercise devices with one measurement device may be very challenging.
An object of the present disclosure is to provide a selector pin so as to alleviate the above disadvantages. The object of the disclosure is achieved by selector pin and bolt element of a selector pin which are characterized by what is stated in the independent claims. The preferred embodiments of the disclosure are disclosed in the dependent claims.
A selector pin according to the present disclosure acts as a measuring device that determines an estimate of the chosen weights in a weight stack based on the mechanical stress on it caused by the weight stack. One aspect of the selector pin according to the present disclosure is structural features of its bolt element. The bolt element can be designed such that only specific contact points on it engage with the weight stack. As a result, more accurate and consistent measurement results can be achieved on a high variety of different weight exercise devices. Another aspect of the selector pin is implementation of orientation-correcting features. For example, the handle element and/or the bolt element designed such that an orientation of the selector pin deviating from a desired orientation results in a torque that acts to turn the selector pin to the desired orientation. Either of the above-mentioned aspects, i.e. the structural features of the bolt element that improve measurement accuracy and the automatic orientation-correcting features, can be implemented on the selector pin independently from the other. However, said aspects are synergistic, and very high accuracy can be achieved in embodiments where both aspects are present.
In the following the invention will be described in greater detail by means of preferred embodiments with reference to the attached drawings, in which
The present disclosure describes a bolt element of selector pin to be used in a weight stack arrangement of a weight exercise machine. A weight stack arrangement typically comprises a weight stack (i.e. a stack of weight plates), a support frame, and an elevator mechanism.
The weight plates 11 and the selector shaft 13 are provided with horizontal selector holes 11.1 and 13.1 so that a desired number of weight plates of the weight stack can be selected for an exercise by inserting a selector pin (i.e. a “weight pin”, a “stack pin”) through the holes 11.1 and 13.1.
In
As explained above, the selector pin is used to select an effective load to be used in the exercise device. In the context of the present disclosure, the term “effective load” (or “weight load” or simply “load”) refers to a resistance resisting actions of a user using the exercise device. In the example of
In order to monitor physical exercise of a person on weight exercise machine, a selector pin according to the present disclosure may be used instead of a conventional selector pin. While the selector pin according to the present disclosure is mostly discussed in reference to the weight stack arrangement of
The present disclosure mainly discusses the selector pin in the context of a method comprises a step performing a dynamic or static exercise with the exercise device while estimating the effective load (i.e. the resistance resulting from the selected portion of the weight stack). However, the use of the selector pin according to the present disclosure is not limited only to such scenarios. Instead, the present disclosure also more generically describes a method for an exercise device with a weight stack, where a desired portion of a weight stack can be selected with a selector pin with a bolt element according to the present disclosure. The method comprises at least a step of providing a selector pin with the bolt element according to the present disclosure and a step of selecting a desired portion of the weight stack with the selector pin and measuring the mechanical stress of the bolt element with the stress sensor of the bolt element.
The use of the selector pin is not limited only to measurements measured during with the exercise. For example, the selector pin may be used to measure user performance prior and after an exercise in order to evaluate fatigue caused by the exercise. In this scenario, it may not be necessary to make measurements during the exercise.
Further, as will become apparent later in the present disclosure, the selector pin may be used as a tool for more extensive monitoring and analysing of exercises (dynamic, static, and any combination thereof) and for providing feedback on the exercises.
In addition, the selector pin according to the present disclosure may also be used for testing purposes. For example, with the selector pin actual weight values of a weight stack may be tested and validated.
A selector pin according to the present disclosure may comprise a bolt element and a handle element at one end of the bolt element. In this context, a bolt element is an element in the form of an elongated, essentially straight bar or bolt that is configured to fit in selector holes or slots of a weight plate and a selector shaft of the weight stack arrangement. A selector pin according to the present disclosure preferably comprises means for estimating the amount of weights being used in an exercise. The amount of weight can be estimated by using a stress sensor to determine mechanical stress the selector pin experiences during the exercise. On one hand, the mass of the weights (e.g. in the form of weight plates of a weight stack) generate a downward force. On the other hand, a user exercising on a weight exercise generates a force that is transformed by the elevator mechanism of the weight stack arrangement into an upward force countering (or exceeding the downward force). These forces cause mechanical stress to the bolt element. The mechanical stress, when measured, can be used for estimating an effective load (i.e. resulting from the selected portion of the weight stack). Further, when coupled with other kind of measurements (e.g. acceleration measurements), very versatile measurement data on the exercise can be generated.
In order to make the mechanical stress measurable, the bolt element may be configured to be elastic and reversibly deformable. However, at the same time, the bolt element should withstand total weight of all weight plates of the weight stack without plastic deformation or breaking). To be able to measure the mechanical stress more accurately, a bolt element according to the present disclosure may have two first contact points positioned along the length of the bolt element on a first side of the bolt element, and a second contact point between the first contact points on a second side opposite to the first side. In the context of the present disclosure, the term “contact point” is intended to be understood as a designated, portion of the bolt element, configured to be in contact with the weight plate and the selector shaft during use.
In the bolt element according to the present disclosure, the first contact points may be configured to engage with the weight plate during an exercise, while the second contact point may be configured to engage with the centre selector shaft. For example, in
In order to ensure that the designated contact points engage with the weight plate and the selector shaft and that essentially the whole load of the selected weight plates is carried by the contact points, the contact points may be elevated from the surface of the bolt element. An elevation may be in the form of a bulge, a bump, or other kind of protrusion, for example. At least one of the first and second contact points may be in the form of such protrusions, extending from the first and second side, respectively. Preferably, at least the first contact points are elevated. Most preferably, all contact points (including the second contact point) are elevated.
Protrusions as discussed above can be formed in different ways. For example, protrusions can be formed by adding material to the surface of the bolt element at the contact points. Alternatively, or in addition, protrusions can be formed by removing material (e.g. by cutting or machining) around the contact points.
To produce a measurement signal representing the mechanical stress experienced by the bolt element, the bolt element may further comprise a stress sensor configured to determine mechanical stress of the bolt element caused by forces generated by the weight plate and the selector shaft acting on the first and second contact points of the bolt element. The stress sensor may be connected to a measurement unit that measures a signal generated by the stress sensor. In some embodiments, the measurement unit is fitted inside the handle element of the selector pin. The measurement unit may comprise an A/D converter, a computing device, a power source (such as a battery) and a wireless transceiver, for example. The computing device may be in the form of a processor and a memory, for example.
Within the context of the present disclosure, the term “stress sensor” refers generically to any sensor that can be used to determine mechanical stress of the bolt element, can be fitted on or inside the bolt element, and is able to produce an electrically measurable signal representing the mechanical stress. Preferably, a strain gauge is used as the stress sensor. A strain gauge may be in the form of a foil attached to the bolt element. Conductor traces on the foil are configured to shorten or lengthen (and at the same time become thicker or thinner) as the object is deformed, thereby causing the electrical resistance of the conductors to change. This change of electrical resistance can then be measured, and an estimate of the strain can be formed based on the measured change of electrical resistance. In
In
In addition, some embodiments of a bolt element according to the present disclosure can produce a sufficient measurement accuracy even without the protrusions. For example, a bolt element with a stress sensor extending most (or essentially the whole) length of the bolt element, such as in the embodiment of
While
For example, in some embodiments, the bolt element may be in the form of a thin, hollow cylinder filled with a fluid. The fluid is preferably essentially incompressible, e.g. pneumatic oil. Forces caused by the weight plates and the selector shaft engaging with the bolt element cause an increase in the pressure of the fluid, and the bolt element may be provided a pressure sensor configured to sense the pressure. In this manner, amount of mechanical stress experienced by the bolt element can be estimated. Similar to the embodiment discussed earlier, the bolt element is preferably provided dedicated contact points: two first contact points positioned along the length of the bolt element on a first side of the bolt element, and a second contact point between the first contact points on a second side opposite to the first side. Further, at least one of the first and second contact points may be in the form of protrusions extending outwards from the shell of the hollow bolt element. Preferably, at least the first contact points are elevated from the surface of the shell. Most preferably, all contact points (including the second contact point) are elevated from the shell surface.
Most of the above-discussed embodiments of a bolt element according to the present disclosure rely on measuring deformation of the bolt element. However, a bolt element according to the present disclosure may also be implemented using other approaches. For example, the bolt element may comprise at least one stress sensor directly at a contact point (i.e. first and/or second contact point) of the bolt element. If the sensors are positioned directly at the contact points as discussed in the two embodiments above, the bolt element itself may be essentially rigid. The at least one stress sensor may be in the form of one or more force-sensing strips or miniature load cell sensors, configured to measure compressive force at the contact points of the bolt element, for example. An estimate of the effective load can be determined based on the measured compressive force.
For example, in some embodiments, a force-sensing strip may be attached on top of one or more contact points. At least one of the contact points may be in the form of protrusions extending outwards from the surface of the bolt element. Preferably, at least the first contact points are elevated from the surface. Most preferably, all contact points (including the second contact point) are elevated from the shell surface. In some embodiments, an elevation may be achieved by positioning a sufficiently thick force-sensing strip on non-protruded contact point of a bolt element. Alternatively, if more prominent elevations are desired, protrusions may be formed on the surface of the bolt element (e.g. similar to the contact points 22.1 and 22.2 in
The above-discussed embodiments discuss determining the amount of stress in one dimension. This kind of approach has the advantage that it requires fewer stress sensors (e.g. strain gauges). As a result, it may be easier and cheaper to implement. Further, as fewer sensors are fitted to the bolt element, it may be easier to ensure sufficient strength (stiffness) and mechanical robustness of the pin. However, when the measurement of stress is limited to one dimension, the measurement may become more prone to measurement errors caused by incorrect orientation of the selector pin. At an orientation perpendicular to the intended orientation, the stress sensor may be almost completely unresponsive to the mechanical stress. In order to ensure accurate measurement of mechanical stress caused to the selector pin, the selector pin may comprise means for correcting its own orientation. In the following, some examples of these orientation-correcting functionalities are discussed in more detail.
In some embodiments, automatic orientation-correcting functionalities of a selector pin may be implemented with structural features of its handle element. For example, the centre of gravity of the handle element may be arranged to be at a distance from (i.e. does not coincide with) a centre axis of the bolt element. For example, a battery of the selector pin may be positioned at a distance from the centre axis. In this manner, the centre of gravity may be shifted further away from the centre axis of the bolt element. By arranging the centre of gravity to be at a distance from the centre axis of the bolt element, a torque leveraging the selector pin can be caused. This torque acts to turn the selector pin to an orientation where the centre of gravity of the handle element is directly below the centre axis of the bolt element. In
Alternatively, or in addition, the bolt element may implement structural features that act to turn the selector pin to a desired orientation. Shapes and/or relative positions of surfaces of the first and second contact points may be configured such that, when an orientation of the selector pin about the centre axis of the bolt element deviates from a desired orientation during use, forces generated by the weight plate and the selector shaft engaging with the contact points cause a torque that acts to turn the selector pin to the desired orientation. For example, surfaces of the first and second contact points may be configured such that, in a plane perpendicular the centre axis of the bolt element, the shortest distance between surfaces of the weight plate and the selector shaft engaging with the contact points of the bolt element is achieved when in the desired orientation.
The automatic orientation-correcting features discussed above in relation to the embodiment of
In addition to a stress sensor, a selector pin according to the present disclosure may comprise other sensors. For example, the selector pin may further comprise an orientation sensor configured to sense the orientation of the bolt element with respect to the direction of gravity. The orientation sensor may be in the form of an acceleration sensor, for example. The acceleration sensor is preferably at least a 2D accelerometer. The accelerometer may be a MEMS accelerometer, for example. However, other orientation sensors may be used instead. For example, various gravity-assisted mechanical arrangements may be used for determining the selector pin's orientation with respect to the horizontal plane.
The computing device of the measurement unit may be configured to receive measurement signals from the stress sensor and the orientation sensor and calculate an estimate of a total weight of selected by the user on the weight exercise device based on the measurements from the strain gauge and the orientation sensor. Calculating the estimate may comprise steps of estimating total weight based on the strain gauge measurements and compensating the total weight based on the orientation sensor measurements, for example. In this manner, any deviation remaining in orientation of the selector pin (after automatically correcting the orientation) can be compensated. In some embodiments, the selector pin is implemented without any automatic orientation-correcting features, and the determining of value of the selected weight may be based solely on compensating the deviation via calculation.
As an alternative (or in addition) to automatic orientation-correcting features, the selector pin may comprise user-assisted orientation-correcting features. For example, the selector pin may further comprise at least one indicator element, such as a speaker, one or more LEDs or a display. In some embodiments, the computing device of the measuring unit may be configured to produce indicators on the at least one indicator element based on the measurements from the orientation sensor. Alternatively, the indicator element may be a simple, passive indicator (e.g. an arrow formed on the surface of the handle element) indicating which part of the selector pin should be pointing down (or up). The indicator or indicators provide information aiding a user to orient the selector pin to a desired orientation (e.g. by manually turning the selector pin in the selector hole to the desired orientation). In this manner, the user is able to orient the selector pin correctly, if automatic orientation-correcting features of the selector pin fail to do so, or, in some embodiments, if automatic features are not present.
With a selector pin comprising a stress sensor as described in the above embodiments, an estimate of effective weight load used on a weight exercise device during an exercise can be formed. Further, when coupled with measurement data from an acceleration sensor, very versatile information on the exercise can be produced. For example, estimates on how much work was done (i.e. how much energy was consumed) during an exercise and how efficiently the exercise was performed can be formed based on the estimated effective load and acceleration. Estimates may be formed even for each repetition of a movement in an exercise.
A computing device of the selector pin may be configured to provide feedback for the user on an indicator element in the selector pin. This indicator element may be the same indicator element that was used for prompting the user to orient selector pin correctly. Alternatively, a different indicator element may be used on the selector pin. In addition, as briefly mentioned earlier, the selector pin may comprise a wireless transceiver (or a wireless transmitter). A computing device on the selector pin may be configured to send measurement information originating from the sensors on the selector pin to an external device capable of receiving said data via the wireless transceiver. The external device may be a computer, a mobile phone, a fitness tracker watch, or a tablet computer, for example. A selector pin according to the present disclosure may be configured to determine the mechanical stress of the bolt element and/or the orientation of the selector pin and send it to the external device for further processing and analysis. The external device may then be used to display the processed and analysed data. The selector pin may be configured to send the measurement data to the external device in real time or to store data to a memory and send it to the external device later. In order to save battery power, computationally more intensive tasks may be performed on the external device, while the computing unit of the selector pin may be configured to perform only light computational tasks, such as pre-processing of the measured data. Alternatively, the computing device of the selector pin may be configured to implement the functionalities of further processing and analysing of the measured data and the indicator unit of the selector pin may be in the form of a display configured to display feedback on the processed and analysed data.
While the selector pins in the above-discussed embodiments all comprise a stress sensor of some kind, a selector pin according to the present disclosure may also be implemented without a stress sensor. For example, in some embodiments, the selector pin may comprise an acceleration sensor and the selector pin may be configured to provide information on user actions during a weight exercise device based on the acceleration sensor. For example, the selector pin may be configured to produce information number and speed of repetitions in an exercise. The use of an orientation-correcting feature according to the present disclosure (e.g. in the form of an automatic orientation correcting feature and/or a feature prompting user to correct the orientation) is preferable even in embodiments where no stress sensor is used. By having an orientation-correcting feature, effects of gravity to measurements produced by the acceleration sensor can be compensated more easily, or the measurements can be used without compensation.
It is obvious to a person skilled in the art that the selector pin and its bolt element can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20206277 | Dec 2020 | FI | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/FI2021/050858 | 12/9/2021 | WO |
