Patent Publication Number: US-2023135743-A1

Title: System and method to resist motion of human powered vehicles

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to, and the benefit of, U.S. Provisional Patent Application No. 63/275,203, filed on Nov. 3, 2021, and titled “SYSTEM AND METHOD TO RESIST MOTION OF HUMAN POWERED VEHICLES,” which is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     Since the inception of human powered vehicles such as bicycles, the cycling world has focused on certain objectives: decreasing the weight of the bicycle, increasing the speed of the bicycle, and decreasing the effort required to maintain the speed of the bicycle. Human powered vehicles have also been developed to operate in a stationary manner to allow the cyclist to exercise in place. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG.  1    shows an example of a system that can magnetically add or reduce resistance to a pedaling mechanism of a human powered vehicle according to various embodiments of the present disclosure. 
         FIG.  2    shows another example of a system that can magnetically add or reduce resistance to a pedaling mechanism of a human powered vehicle according to various embodiments of the present disclosure. 
         FIG.  3    shows another example of a system that can magnetically add or reduce resistance to a pedaling mechanism of a human powered vehicle according to various embodiments of the present disclosure. 
         FIG.  4    shows an example of a static magnet holding bracket illustrated in  FIG.  1    according to one embodiment of the present disclosure. 
         FIG.  5    shows one example of a static magnet holding bracket illustrated in  FIG.  4    according to one embodiment of the present disclosure. 
         FIG.  6    shows an adjustable magnet holding bracket illustrated in  FIG.  2    according to one embodiment of the present disclosure. 
         FIG.  7    shows one example an adjustable magnet holding bracket of  FIG.  3    according to one embodiment of the present disclosure. 
         FIG.  8    shows another example of an adjustable magnet holding bracket of  FIG.  3    according to one embodiment of the present disclosure. 
         FIG.  9    shows a portion of the adjustable magnet holding bracket of  FIG.  8    according to one embodiment of the present disclosure. 
         FIG.  10    shows another example of an adjustable magnet holding bracket of  FIG.  3    according to one embodiment of the present disclosure. 
         FIG.  11    shows another example of an adjustable magnet holding bracket of  FIG.  3    according to one embodiment of the present disclosure. 
         FIG.  12    shows a schematic block diagram of a computing device according to various embodiments of the present disclosure. 
         FIGS.  13  and  14    are flowcharts illustrating examples of functionality implemented as portions of a control system executed in the computing device of  FIG.  12    according to various embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     According to various embodiments, systems and methods are set forth herein that facilitate providing for static and variable wattage consumption when riding a human powered vehicle such as a bicycle. Various embodiments are set forth that allow for the addition of a static resistance to the wheels of the human powered vehicle that require a rider to apply a greater wattage to propel the vehicle forward. In other embodiments, the resistance created can vary over time in accordance with a desired wattage. Such desired wattage may be selected by a rider, obtained from a predefined wattage per distance file, or the desired wattage may be specified in some other manner. According to one embodiment, the resistance applied to a pedaling mechanism of a moving bicycle is accomplished by the use of magnets as will be described. 
     With reference to  FIG.  1   , shown is an illustration of a human powered vehicle  100   a  that comprises, for example, a bicycle. Although the human powered vehicle  100   a  is shown as a bicycle, it is understood that the human powered vehicle  100   a  may comprise other types of vehicles such as unicycles, tricycles, quadracycles, or other vehicles. Furthermore, assuming the human powered vehicle  100   a  is a bicycle, then it may comprise road bicycles, mountain bicycles, hybrid bicycles, recumbent bicycles, touring bicycles, and other bicycles. 
     The human powered vehicle  100   a  includes front and rear wheels  103  that spin about an axle. Each wheel  103  includes a hub  106 . Each axle fits through a respective one of the hubs  106  and connects to a frame  109 . In various embodiments, the central hubs  106  are core portions of the wheels  103 , and each of the central hubs  106  includes a set of bearings around which one of the wheels  103  rotates. A number of front or rear spokes  113  connect the rims of the wheels  103  to the hubs  106 . 
     In order to magnetically add or reduce resistance to the human powered vehicle  100   a  while moving, according to various embodiments, the human powered vehicle  100   a  includes front and rear conducting discs  116  that are connected to the front and rear wheels  103 , respectively, via the central hubs  106 . The conducting discs  116  are fixed to the wheels by way of the hubs  106  or other structure so as to spin around the axles along with the wheels  103 . As such, the conducting discs  116  spin or rotate along with the wheels about the rotational axes of the wheels  103  when a cyclist engages the pedals  119  or other structure to generate force to move the human powered vehicle  100   a.    
     Also, the human powered vehicle  100   a  includes one or more magnet holding brackets  123  that are attached to the frame  109 . As shown, the magnet holding brackets  123  are positioned adjacent to or near each of the conducting discs  116 . The magnet holding brackets  123  hold one or more magnets  126 . In the various embodiments, the magnets  123  may comprise a permanent magnet, an electromagnet, or other type of magnetic material. 
     Although the human powered vehicle  100   a  is shown in  FIG.  1    as including both the front and the rear conducting discs  116  and their corresponding magnet holding brackets  123 , other embodiments may include only a single conducting disc  116 /magnet holding bracket  123  on one of the wheels  103 . To this end, there may be one or more conducting discs  116  and corresponding magnet holding brackets  123  on a given human powered vehicle  100   a  limited by the total number of wheels or configurations employed. For example, it may be possible to link multiple magnet holding brackets  123  on a single wheel such as on both sides of a wheel or at different locations on the wheel as will be described. 
     In various embodiments, the conducting discs  116  can be composed of copper, aluminum, steel, or any other conducting metal, or any combination of one or more such conducting metals. The conducting discs  116  may comprise a solid disc or the conducting discs  116  may have voids. For example, in one embodiment, the conducting discs  116  may be a ring with spokes. In one approach, the conducting discs  116  may replace a friction brake disc in a conventional bicycle. 
     To magnetically apply resistance to the pedaling mechanism of the human powered vehicle  100   a , the conducting discs  116  are exposed to one or more magnets that can be placed in receptacles (not shown) of the magnet holding brackets  123 . In some embodiments, the magnet holding brackets  123  can be fixedly attached to the frame  109  through bolts, clamps, weld adhesives, screws, or other means of attachments. The magnet holding brackets  123  are positioned on the human powered vehicle  100   a  relative to the conducting discs  116  so that a magnetic field of the magnets placed in the static magnet holding bracket  123  intersects with the conducting discs  116 . As a rider rides the human powered vehicle  100   a , the conducting discs  116  rotate, and eddy currents are induced in the conducting discs  116  by way of electromagnetic induction given that the magnetic fields of the magnets intersect with the conducting discs  116 . The configuration of  FIG.  1    shows a static version of a magnet holding bracket  123  such that it does not move and the magnets  126  positioned on the magnet holding bracket  123  are maintained in a static position relative to the conducting disc  116  when either at rest or in motion. 
     The eddy currents produce a counter electromagnetic field that opposes the magnetic field of the magnets. As a result, the conducting discs  116  experience a drag force from the magnets  126  that opposes their rotation. The magnitude of the force that opposes the rotation of the conducting discs  116  depends on the size of the conducting disc  116 , the number of magnets or magnitude of the magnetic flux that intersects with the conducting disc  116 , the rotational velocity of the conducting disc  116 , and on other factors. 
     Accordingly, the eddy currents produced on the conducting discs  116  oppose rotation of the wheels  103  and, correspondingly, increase the resistance experienced by a rider of the human powered vehicle  100   a , thereby making pedaling more difficult for the rider. As the embodiments discussed by way of FIG.  1  relate to a passive system with static magnet holding brackets  123 , once the magnets  126  are placed in the static magnet holding brackets  123 , the positioning of the magnets  126  generally may not be changed unless the cyclist stops the human powered vehicle  100   a  and manually changes the position of the magnets  126  on the magnet holding bracket(s)  123 , or removes the magnets  126  from the magnet holding bracket(s)  123 . However, in other embodiments, active systems may be employed in which the positioning of the magnets  126  relative to the conducting discs  116  can be changed dynamically while the human powered vehicle is moving as will be described. 
     The passive system embodiments described above can be useful for a cyclist who wishes to train with a certain level of added resistance. Additionally, the passive system embodiments described above can be useful for a cyclist who does not need to vary the amount of resistance added during the training session. For example, a cyclist may be training for a race or a meet but may only be able to train on flat terrain. Training on flat terrain may provide inadequate preparation for a race. For example, without the added magnetic resistance, the cyclist may exert an average power output of 250 watts during a training session on the flat terrain averaging a certain velocity. However, the cyclist may wish to exert an average power output of 300 watts on the same flat terrain while averaging a similar velocity. To achieve this, the cyclist can place magnets into the front static magnet holding bracket  123  and/or rear static magnet holding bracket  123  and then begin a training session. The cyclist, on the flat terrain, will need to generate more power to maintain a predefined velocity with the magnets  126  in place, thereby experiencing a workout with a higher level of exertion than a workout without use of the magnets  126 . 
     To give another example, a cyclist may wish to train at a lower velocity while maintaining a similar exertion level in trials or paths, for example, where other traffic such as pedestrians may exist or where a rider wishes to train with a partner with lesser ability. Accordingly, the rider can add magnets  126  to one or more magnet holding brackets  123  which will require the rider to maintain a desired level of exertion while training at a slower velocity. 
     To gauge the power exerted, the human powered vehicle  100   a  includes a power meter  129 , which is a device that can measure a cyclist&#39;s average power output or exertion level, during a cycling session in terms of watts. In various embodiments, the power meter  129  can measure instantaneous power output, average power output over a duration of time, or a total power output exerted over a certain distance. Although  FIG.  1    illustrates the power meter  129  being placed on the pedal  119  of a human powered vehicle  100   a  comprising a bicycle, the power meter  129  can be placed on other various parts of the human powered vehicle  100   a  such as the crank arm  133  or the central hubs  106 . The power meter  129  may employ strain gauges to measure applied torque and, when combined with angular velocity, can calculate power output in terms of watts. In various embodiments, the power meter  129  is communicatively coupled to a computing device  136  through WiFi, Bluetooth®, near-field communication (NFC), radio-frequency identification (RFID), wireless infrared, ultra-wideband, wireless induction, long range (LoRa), Z-Wave®, ZigBee®, and other wireless communication methods. The computing device  136  may include a display device that displays, among other information, the watts generated by the rider at a given instant. Accordingly, a cyclist can view his or her power output in real time through a display of the computing device  136 . 
     Referring next to  FIG.  2   , shown is an illustration of human powered vehicle  100   b  according to an embodiment of the present disclosure. The human powered vehicle  100   b  includes many of the same components as the human powered vehicle  100   a  ( FIG.  1   ) except as set forth in the description below, where like components are denoted with the same reference numbers. 
     The human powered vehicle  100   b  further includes adjustable magnet holding brackets  143  that are positioned adjacent to the conducting discs  116 . Each of the adjustable magnet holding brackets  143  is linked to levers  153  by way of a cable  156 . Each cable  156  includes, for example, an inner cable (not shown) and a housing (not shown). In some embodiments, a housing may not be used at least along portions of the cable  156 . 
     Each of the adjustable magnet holding brackets  143  provides for movement of the magnets  126  relative to one or two sides of a respective conducting disc  116 . Specifically, the adjustable magnet holding brackets  143  facilitate movement of the magnets  126  away from and closer to a respective conducting disc  116 . As one or more magnets  126  are moved closer to a side of a given conducting disc  116 , the density of the magnetic field of the magnet  126  that intersects with conducting disc  116  increases. Conversely, as the one or more magnets  126  are moved away from a side of a given conducting disc  116 , the density of the magnetic field of the magnet  126  that intersects with the conducting disc  116  decreases. 
     The cables  156  are attached to the levers  153  and transfer force generated by the levers  153  into movement or adjustment of the adjustable magnet holding brackets  143  such that the magnets  126  held by the adjustable magnet holding brackets  143  are moved away from or closer to the conducting disc  116 . In this manner, a rider of the human powered vehicle  100   b  can control the amount of force generated by virtue of eddy currents in the conducting discs  116  by positioning a respective lever  153 , thereby moving the magnets closer to or away from a respective conducting disc  116 . The force that opposes the movement of the human powered vehicle  100   b  can be manually adjusted accordingly. According to one embodiment, a rider can see the watts consumed on a display device  136  of the computing device  136  and can position one or more levers  153  to create more or less force opposing the movement of the human powered vehicle  100   b  such that a desired wattage is maintained. The functionality of how a given adjustable magnet holding bracket  143  moves magnets  126  relative to a conducting disc  116  is described with respect to later figures. 
     Referring next to  FIG.  3   , shown is an illustration of human powered vehicle  100   c  according to an embodiment of the present disclosure. The human powered vehicle  100   c  includes many of the same components as the human powered vehicles  100   a  ( FIG.  1   ) and  100   b  ( FIG.  2   ) except as set forth in the description below, where like components are denoted with the same reference numbers. 
     The human powered vehicle  100   c  includes adjustable magnet holding brackets  163 . According to one embodiment, the adjustable magnet holding brackets  163  include electric components or other components such as, for example, linear or rotary actuators that cause adjustment of the adjustable magnet holding brackets  163 , thereby moving the magnets  126  held by the adjustable magnet holding brackets  163  closer to or away from the conducting discs  116 . Alternatively, the adjustable magnet holding brackets  163  may include electromagnets that generate a variable magnetic field as will be discussed. 
     The human powered vehicle  100   c  includes a computing device  166  that facilitates control of the adjustable magnet holding brackets  163  as will be described. The computing device  166  is connected to actuators on the adjustable magnet holding brackets  163  by way of wires  169 . 
     The computing device  166  is configured to execute a control system (not shown) that controls the positioning of magnets  126  relative to the conducting discs  116  to generate a force that opposes the movement of the human powered vehicle  100   c . The position of the magnets  126  relative to the conducting discs  116  is determined by controlling the actuators associated with each of the adjustable magnet holding brackets  163 . 
     According to one embodiment, the control system executed by the computing device  166  facilitates an input of a desired wattage value by the rider. The control system obtains a signal from the power meter  129  that indicates the actual wattage applied by a rider to the human powered vehicle  100   c  at a given instant. The control system controls the positioning of the adjustable magnet holding brackets  163  to vary the force opposing the movement of the human powered vehicle  100   c  due to the eddy currents in the conducting discs  116  generated by the proximity of the magnets  126  to the conducting discs  116 . In this manner, the control system can control the magnitude of the force opposing the movement of the human powered vehicle  100   c  at a given instant so that the wattage it takes to move the human powered vehicle  100   c  forward is as close as possible to the desired wattage value input by the rider. 
     During the operation of the human powered vehicle  100   c , it may occur that the adjustable magnet holding bracket  163  reaches the maximum limit of its motion. That is to say, the control system executed by the computing device  166  may move the magnets  126  to a position such that the magnets  126  are the farthest away from or closest to the conducting disc  116 . In such a circumstance, it may not be possible to maintain the desired wattage input by the rider. 
     In addition, in another embodiment, a wattage-per-distance record may be stored in a memory associated with the computing device  166  that specifies a desired wattage that changes over a given distance. Such wattage-per-distance records may emulate the wattage that would need to be expended, for example, over a race course or a section of a long race such as a portion of the Tour de France. In this manner, the computing device  166  can control the wattage it takes to operate the human powered vehicle  100   c  to simulate the terrain of a given course for purposes of training. This would be especially advantageous if the course upon which a rider trains is generally flat as compared to the course of the race for which one is training. It should be noted that the various systems and components discussed above with reference to  FIGS.  1 ,  2 , and  3    may be implemented along with other systems on the human powered vehicles  100   a ,  100   b , and  100   c . For example, such human powered vehicles  100   a ,  100   b , and  100   c  may include gears, friction brakes, and other systems and structures. 
     With reference to  FIG.  4   , shown is an example static magnet holding bracket  123 , denoted herein as static magnet holding bracket  123   a , that can be used to oppose movement of the human powered vehicle  100   a  ( FIG.  1   ) according to an embodiment of the present disclosure. As shown, the static magnet holding bracket  123   a  is fixedly positioned relative to one of the conducting discs  116 . According to various embodiments, the magnet holding bracket  123   a  includes one or more receptacles  183  that are configured to receive the one or more magnets  126 . For example, the one or more magnets  126  can be inserted into the receptacles  183  and be exposed to one side of the conducting disc  116 . Each of the receptacles  183  is shaped so that a magnet  126  will fit therein. To this end, each of the receptacles  183  may comprise, for example, a tapered recess, or a recess with projections or a stop that prevent a magnet  126  from passing through the receptacle  183 . In one embodiment, each of the receptacles  183  may include a shelf that abuts with a projection on a magnet  126  when the magnet  126  is placed in the receptacle  183 . 
     In one embodiment, the magnetic attraction between the material of the receptacle  183  and the magnet  126  holds the magnet  126  in the receptacle  183 . Alternatively, the magnetic attraction between the material of the disc  116  and the magnet  126  holds the magnet  126  in the receptacle  183 . 
     Although a circular shape is shown for the receptacles  183  to accommodate circular or spherical magnets  126 , the receptacles  183  can include other suitable shapes to fit various magnet shapes, such as rectangular, cylindrical, bar shaped, horseshoe shaped, and other shapes. As discussed above, the magnets  126  can include permanent magnets or electromagnets. Permanent magnets that may be used include ceramic, alnico, samarium cobalt, neodymium iron boron, injection molded, and other types of permanent magnets. 
     In one embodiment, one or more magnets  126  may be placed in the respective receptacles  183  such that the number of receptacles  183  that include a magnet  126  may vary. In this manner, one may vary the force that opposes the movement of the human powered vehicle  100   a  by varying the number of magnets  126  placed into various receptacles  183 . In addition, the force opposing the movement of the human powered vehicle  100   a  may vary based upon the placement of the magnets  126  relative to the conducting disc  116 . That is to say, magnets  126  placed closer to the center of the conducting disc  116  will generate less force than magnets  126  placed closer to the outer rim of the disc  116 . Thus, the magnitude of the force opposing the movement of the human powered vehicle  100   a  may vary based on the number of magnets  126  placed in the receptacles  183  and the position of the respective magnets  126  in respective receptacles  183  relative to the conducting disc  116 . 
     Turning to  FIG.  5   , shown is a side view of the static magnet holding bracket  123   a  that can be used to oppose movement of the human powered vehicle  100   a  ( FIG.  1   ) according to an embodiment of the present disclosure. As shown, the static magnet holding bracket  123   a  incorporates a dual sided design such that the magnets  126  are placed within receptacles  183  are exposed to both sides of the conducting disc  116 .  FIG.  5    illustrates four of the magnets  126  positioned relative to one side of the conducting disc  116  and another four of the magnets  126  positioned relative to a second side of the conducting disc  116 . In other embodiments, the static magnet holding bracket  123   a  can include more or less than four of the magnets  126  positioned relative to either side of the conducting disc  116 . In another alternative, the static magnet holding bracket  123   a  may comprise a single sided design in which magnets  126  are positioned only on a single side of the conducting disc  116 , where the static magnet holding bracket  123   a  includes only a single side. This approach may be desirable if clearance with other components of the wheel requires a single sided approach. 
     The static magnet holding bracket  123   a  further includes one or more bearings  203  positioned within sleeves  206 . The bearings  203  are positioned adjacent to each of the magnets  126  to separate the static magnet holding bracket  123   a  from the conducting disc  116 . Specifically, the bearings  203  separate the magnets  126  from the conducting disc  116 . For example, without the bearings  203 , the magnets  126  might make contact with the conducting disc  116 , which would create unwanted friction between the magnets  126  and the conducting disc  116 . To this end, the bearings  203  act to bring the magnets  126  as close as possible to the conducting disc  116  without creating physical contact between the magnets  126  and the conducting disc  116 . This facilitates a magnetic field from the magnets  1126  with a higher density being incident to or exposed to the conducting disc  116  than if the magnets  126  were positioned further away from the conducting disc  116 . In various embodiments, the bearings  203  can include ball bearings, roller bearings, and other types of bearings. 
       FIG.  6    illustrates an example adjustable magnet holding bracket  143   a  that can be used to oppose movement of the human powered vehicle  100   b  ( FIG.  2   ) according to an embodiment of the present disclosure. The adjustable magnet holding bracket  143   a  is one example of the magnetic holding bracket  143  ( FIG.  2   ). 
     The adjustable magnet holding bracket  143   a  comprises a clamshell configuration incorporating a hinge mechanism  213  and sides  216 , where the sides  216  are positioned relative to the conducting disc  116 . The sides  216  are configured to move toward or away from the conducting disc  116  based on a force generated by virtue of the cable  156  ( FIG.  1   ). An outer jacket of the cable  156  abuts an attachment point  219  and the inner portion of the cable  156  is attached to a second attachment point  223 . The attachment points  219  and  223  are couple to a respective one of the sides  216 . The opposing end of the cable  156  is coupled to levers  153  ( FIG.  2   ) as described above. 
     In another alternative, the adjustable magnet holding bracket  143   a  may comprise a single sided design in which magnets  126  are positioned only on a single side  216  of the conducting disc  116 , where the adjustable magnet holding bracket  143   a  includes only a single side  216 . This approach may be desirable if clearance with other components of the wheel requires a single sided approach. 
     A torsional spring  226  is positioned at the hinge point between the sides  216  to provide a force to pivot the sides  216  away from the conducting disc  116 . The torsional spring  226  may be positioned to be coaxial relative to the hinge mechanism  213 . Each of the pair of sides  216  include receptacles to hold the magnets  126  ( FIG.  3   ). Also, a bearing  203  ( FIG.  5   ) may be positioned on each of the sides  216  so as allow the sides  216  to come as close as possible to the conducting disc  116  while eliminating any friction between the sides  216  and the conducting disc  116  except for the friction that occurs due to the bearing  203  held in its receptacle or other bearing structure. As shown in  FIG.  5   , the bearing  203  comprises a ball bearing. However, it is understood that the bearing  203  may comprise any type of bearing such as, for example, cylindrical bearings, frictionless materials such as Teflon, or other types of bearing between the adjustable magnet holding bracket  143   a  and a conducting disc  116 . 
     With implementation of the adjustable magnet holding bracket  143   a , a rider of the human powered vehicle  100   b  can control the amount of force generated by virtue of eddy currents in the conducting discs  116  by positioning a respective lever  153 . The positioning of the lever  153  causes the cable  156  to pull the attachment points  219  and  223  closer together, thereby causing the magnets  126  disposed in the sides  216  to move further away from the conducting disc  116 . Alternatively, the lever  153  may be positioned such that the attachment points  219  and  223  are positioned farther apart, thereby allowing the magnets  126  disposed in the sides  216  to come closer to the conducting disc  116 . In this manner the distance between the magnets  126  and the conducting disc  116  is varied, thereby varying the amount of force that results from the creation of eddy currents in the conducting disc  116 . It should be noted that the adjustable magnet holding bracket  143   a  is positioned so as to avoid interference with other parts of a bicycle as can be appreciated. 
     With reference next to  FIG.  7   , shown is an example of an adjustable magnet holding bracket  163  ( FIG.  3   ) that is denoted herein as adjustable magnet holding bracket  163   a . The adjustable magnet holding bracket  163   a  is used to oppose movement of the human powered vehicle  100   c  ( FIG.  1   ) according to an embodiment of the present disclosure. 
     The adjustable magnet holding bracket  163   a  includes many of the same components as the static magnet holding bracket  163   a  ( FIG.  4   ) except as set forth in the description below, where like components are denoted with the same reference numbers. The adjustable magnet holding bracket  163   a  further includes electromagnets  233  that are connected to a power source  236 . The electromagnets  233  may comprise resistive electromagnets and other types of electromagnets. The power source  230  can include a direct current (DC) or alternating current (AC) voltage sources. According to various embodiments the power source  230  can include batteries, generators, solar cells, and other types of power sources. 
     In another alternative, the adjustable magnet holding bracket  163   a  may comprise a single sided design in which magnets  126  are positioned only on a single side of the conducting disc  116 , where the adjustable magnet holding bracket  163   a  includes only a single side. This approach may be desirable if clearance with other components of the wheel requires a single sided approach. 
     The electromagnets  233  are attached to the adjustable magnet holding bracket  163   a  such that the magnetic field generated therefrom intersects or falls incident upon the conducting disc  116 . In one embodiment, the electromagnets  233  are attached so as to be positioned and oriented in such a manner so as to maximize the magnetic flux of the magnetic field generated by the electromagnet  233  that falls incident to or intersects with the conducting disc  116  when the electromagnets  233  are operated at maximum setting thereby generating a magnetic field with the largest amount of magnetic flux possible. 
     The adjustable magnet holding bracket  163   a  is termed adjustable herein as the magnetic field generated by the electromagnets  233  is adjustable based on the magnitude of the electrical power or current applied to the electromagnets  233  from the power source  236  at a given moment. To this end, the computing device  166  ( FIG.  3   ) may generate a signal that controls or throttles the amount of power that flows from the power source  236  to the electromagnets  233  at any given time. The signal generated by the computing device  166  may control the actual amount of power applied to the electromagnets  233  using various electrical techniques, or the computing device  166  may include power generation and control circuitry by which a current is generated that flows directly to the electromagnets  233 . In the latter case, the power source  236  may be electrically coupled to the computing device  166  to generate such current as opposed to being connected to the electromagnets  233  as shown in  FIG.  7   . 
     Thus, adjustable magnet holding bracket  163   a  with the electromagnets  233  can generate a variable force that opposes the movement of the human powered vehicle  100   c  ( FIG.  3   ). A rider is able to manually adjust the magnitude of such opposing force by controlling the current applied to the electromagnets  233  and thereby control the amount of wattage of opposing force generated thereby. Alternatively, a predefined program may be executed in the computing device  166  that automatically controls current applied to the electromagnets  233 , thereby controlling the magnitude of the opposing force generated at a given instant as the human powered vehicle  100   c  travels as will be described in greater details with reference to later figures. 
       FIG.  8    illustrates an example adjustable magnet holding bracket  163   b  that can be used to oppose movement of the human powered vehicle  100   c  ( FIG.  3   ) according to an embodiment of the present disclosure. The adjustable magnet holding bracket  163   b  is positioned relative to the conducting disc  116  and includes a base  243  that is fixedly connected to the frame  109  of the human powered vehicle  100   c . Further, the adjustable magnet holding bracket  163   b  includes a movable tray  246  that can hold one or more magnets  126 . To illustrate, the movable tray  246  includes receptacles  249  that can receive the one or more magnets  126 . The one or more magnets  126  can include permanent magnets, electromagnets, and other types of magnets. 
     The movable tray  246  is configured to move along rails  253  by way of an actuator  256  and threaded shaft  266 . The actuator  256 , which is controlled by a control system (not shown) implemented in the computing device  166  ( FIG.  3   ), can be configured to rotate a screw shaft  259  that causes the moveable tray  246  to move linearly along the rails  253 . The moveable tray  246  includes a threaded hole through which the screw shaft  259  is threaded. The actuator  256  may comprise a motor, stepper motor, or other type of rotating element. As an alternative, rather than using the rails  253 , the base  243  may include shaped grooves and the moveable tray  246  may include projections that fit into the shaped grooves that hold the moveable tray  246  to the base  243  and allow the moveable tray  246  to slide along the grooves. In either configuration, the moveable tray  246  moves in either direction along a linear axis as shown. In addition, it should be noted that the moveable tray  246  is positioned on the inside of the base  243  such that the magnets  126  in the moveable tray  246  are placed as close as possible to the conducting disc  116 . 
     The adjustable magnet holding bracket  163   b  is adjustable in that the variable positioning of the magnets  126  relative to the conducting disc  116  varies the opposing force created by the eddy currents in the conducting disc  116 . In this manner, the rider may specify a desired wattage that opposes the movement of the human powered vehicle  100   c . To this end, the computing device  166  may generate a driving signal that is applied to the actuator  256  that rotates the screw shaft  259  to move the moveable tray  246  to a desired position such that the magnetic fields of more or less magnets  126  falls incident to the conducting disc  116 , thereby generating a desired wattage that is born by the rider as they pedal or otherwise propel the human powered vehicle  100   c . As shown the adjustable magnet holding bracket  163   b  comprises a single sided design in which magnets  126  are positioned only on a single side of the conducting disc  116 . As an alternative, a double sided approach may be employed where the moveable tray  246  straddles two sides of the conducting disc  116 . 
       FIG.  9    illustrates a sectional view of the movable tray  246  that moves along the rails  253 . The moveable tray  246  includes rail connectors  271  through which the rails  253  slide, thereby connecting the moveable tray  246  to the rails  253 . 
     The movable tray  246  includes a threaded hole to accommodate the threaded shaft  259 . As shown, the rails  253  comprise cylindrically shaped rods, but may also comprise rods of different shapes that facilitate motion of the moveable tray  246  as can be appreciated. 
       FIG.  10    illustrates an example adjustable magnet holding bracket  163   c  that can be used to oppose movement of the human powered vehicle  100   c  ( FIG.  3   ) according to an embodiment of the present disclosure. The adjustable magnet holding bracket  163   c  includes a clamshell bracket incorporating a hinge mechanism  213  and is positioned relative to the conducting disc  116 . The adjustable magnet holding bracket  163   c  further includes a pair of sides  216  that are configured to be drawn toward or away from the conducting disc  116  based on an actuating force applied by actuator  273 . The actuator  273  may comprise, for example, a motor, stepper motor, or other actuator. The actuator  273  connects to the pair of sides  216  through movable extensions  276  that are connected to the sides by way of pivot points  279 . A screw shaft  283  is positioned though threaded holds in the moveable extensions  276 . Each of the sides  216  include receptacles to hold the magnets  126  ( FIG.  3   ). 
     In another alternative, the adjustable magnet holding bracket  163   c  may comprise a single sided design in which magnets  126  are positioned only on a single side of the conducting disc  116 , where the adjustable magnet holding bracket  163   b  includes only a single side. This approach may be desirable if clearance with other components of the wheel requires a single sided approach. 
     The actuator  273  is controlled by a control system (not shown) implemented by way of the computing device  166  ( FIG.  3   ). The actuator  273  can be configured to rotate the threaded shaft  312 , thereby causing the sides  216  to move toward or away from the conducting disc  116 . In this manner, the magnets  126  may be positioned either closer to or further away from the conducting disc  116 . This relative positioning of the magnets  126  and the conducing disc  116  creates a greater or lesser amount of force opposing the movement of the human powered vehicle  100   c . As the pair of sides  216  are drawn closer to the conducting disc  116 , the magnets  126  apply a denser magnetic field to the conducting disc  116 , thereby applying a greater opposing force against the movement of the human powered vehicle  100   c . In one embodiment, when the threaded shaft  312  is rotated in a given direction, a torsional spring  286  helps facilitate the drawing motion of the pair of sides  216 . 
       FIG.  11    illustrates an example adjustable magnet holding bracket  163   d  that can be used to oppose movement of the human powered vehicle  100   c  ( FIG.  3   ) according to an embodiment of the present disclosure. The adjustable magnet holding bracket  163   d  includes a hinge mechanism  293  that facilitates its movement. The adjustable magnet holding bracket  163   d  is a pivoting fender structure  296  with two sides that can be configured to be drawn toward or away from the conducting disc  116  based on an actuating force applied by an actuator  299 . When the adjustable magnet holding bracket  163   d  is drawn toward the conducting disc  116 , the pivoting fender structure  296  can completely cover a portion of the conducting disc  116  as can be appreciated. To this end, the pivoting fender structure  296  includes two sides that straddle the conducting disc  116  when the adjustable magnet holding bracket  163   d  partially or fully engaged. The pivoting fender structure  296  pivots about a pivot point of the hinge mechanism  293 . 
     The adjustable magnet holding bracket  163   d  further includes an attachment extension  303  that includes a threaded hole that accommodates a threaded shaft  306 . In this manner, the attachment extension  303  is configured to pivot as the pivoting fender structure  296  is raised or lowered by the rotation of the threaded shaft  306 . Further, the adjustable magnet holding bracket  163   d  includes receptacles  309  into which the magnets  126  are positioned. As shown, the adjustable magnet holding bracket  163   d  includes the receptacles  309  on one side. However, in various embodiments, the adjustable magnet holding bracket  163   d  includes the receptacles  309  on both sides such that the magnetic fields from magnets  126  disposed in the receptacles fall incident to the conducting disc  116  when the pivoting fender structure  296  is partially or fully engaged with the conducting disc  116 . 
     During operation, the actuator  299  is controlled by a control system (not shown) implemented in the computing device  166  ( FIG.  3   ). The actuator  299  can be configured to rotate the threaded shaft  306 , thereby causing the pivoting fender structure  296  to move toward a portion of the conducting disc  116  where the sides of the pivoting fender structure  296  straddle the conducting disc  116 . Conversely, the actuator  299  may rotate the threaded shaft  306  in the opposite direction, thereby retracting the pivoting fender structure  296  away from the conducting disc  116 . The adjustable magnet holding bracket  163   d  includes a stop  313  at the maximum limit of motion of the pivoting fender structure  296  toward the conducting disc  116 . To this end, the stop  313  can prevent the pivoting fender structure  296  from physically contacting the conducting disc  116 . 
     In another alternative, the pivoting fender structure  296  may comprises a single sided design in which magnets  126  are positioned only on a single side of the conducting disc  116 , where the pivoting fender structure  296  includes only a single side. This approach may be desirable if clearance with other components of the wheel requires a single sided approach. 
     With reference to  FIG.  12   , shown is a schematic block diagram of the computing device  166  implemented in the human powered vehicle  100   c  ( FIG.  3   ) according to various embodiments of the present disclosure. Various applications and/or other functionality may be executed in the computing device  166  according to various embodiments. Also, various data is stored in a memory  403  that is accessible to the computing device  166 . The memory  403  may be representative of a plurality of memories  403  as can be appreciated. The data stored in the memory  403 , for example, is associated with the operation of the various applications and/or functional entities described below. 
     The computing device  166  may comprise, for example, a processor-based system such as a computer system. Such a computer system may be embodied in the form of a desktop computer, a laptop computer, personal digital assistants, cellular telephones, smartphones, set-top boxes, music players, web pads, tablet computer systems, game consoles, head mounted displays, voice interface devices, or other devices. The computing device  166  may include a display. The display may comprise, for example, one or more devices such as liquid crystal display (LCD) displays, gas plasma-based flat panel displays, organic light emitting diode (OLED) displays, electrophoretic ink (E ink) displays, LCD projectors, or other types of display devices, etc. 
     The computing device  166  includes at least one processor circuit, for example, having a processor  400  and the memory  403 , both of which are coupled to a local interface  405 . To this end, the computing device  166  may comprise, for example, at least one server computer or like device. The local interface  405  may comprise, for example, a data bus with an accompanying address/control bus or other bus structure as can be appreciated. 
     Stored in the memory  403  are both data and several components that are executable by the processor  400 . In particular, stored in the memory  403  and executable by the processor  400  is a control system  406 , and potentially other systems and/or applications. Also stored in the memory  403  may be desired wattage  409 , wattage-per-distance record  415 , and other data. In addition, an operating system may be stored in the memory  403  and executable by the processor  400 . 
     In various embodiments, the control system  406  facilitates the movement of the adjustable magnet holding brackets  163  based on a differential between the desired wattage  409  inputted by a rider and the actual wattage collected by the power meter  129  ( FIG.  3   ). For example, the control system  406  operates to adjust the positioning of the magnets  126  relative to the conducting discs  116  to maintain a desired wattage  409  entered by a rider as the rider propels the human powered vehicle  100   c.    
     In other embodiments, the control system  406  facilitates the movement of the adjustable magnet holding brackets  163  based on a differential between wattage values stored in the wattage-per-distance record  415  and the actual wattage collected by the power meter  129  over a distance traveled. Such wattage-per-distance records  415  may emulate the wattage that would need to be expended, for example, over a race course or a section of a long race such as a portion of the Tour de France based on actual wattage measurements taken from such courses given factors such as the weight of the bicycle and rider and potentially other factors. As a rider propels the human powered vehicle  100   c , the control system  406  operates to adjust the positioning of the magnets  126  so that the actual wattage sensed by the power meter  129  over a distance traveled approximately equals the wattage values stored in the wattage-per-distance record  415  implemented on the computing device  166 . 
     With reference to  FIG.  13   , shown is a flowchart that provides one example of the operation of a portion of the control system  406  according to various embodiments. To this end, the flowchart of  FIG.  13    sets forth functionality of the control system  406  in determining a current desired wattage that is used to adjust the positioning of the magnets  126  relative to the conducting discs  116 . The current desired wattage may be entered by a rider or it may be taken from a wattage-per-distance record  415  ( FIG.  12   ) as will be discussed. It is understood that the flowchart of  FIG.  13    provides merely an example of the many different types of functional arrangements that may be employed to implement the operation of the portion of the control system  406  as described herein. As an alternative, the flowchart of  FIG.  13    may be viewed as depicting an example of elements of a method implemented in the computing device  166  ( FIG.  12   ) according to one or more embodiments. 
     Beginning with box  460 , the control system  406  initializes its operation and sets a default desired wattage  409  ( FIG.  12   ). The default desired wattage  409  may be set at zero or some other value that is maintained until changed by a user. As a result, whenever the rider first begins operating the human powered vehicle  100   c  and activates the control system  406 , the control system  406  will set the default desired wattage  409  to zero. Thereafter, the control system  406  will allow the user to change the desired wattage  409  or select a file from the wattage-per-distance record  415  as will be described. 
     Next, in box  463 , the control system  406  determines whether an input has occurred indicating whether the current desired wattage  409  is to be changed. Such would be the case if a user manipulates an input device associated with the computing device  166  to enter a value of the desired wattage  409 , or to increment or decrement the desired wattage  409 . 
     Alternatively, the desired wattage  409  may be adjusted based on metrics that vary over time. For example, the pulse of the rider may be obtained from a sensor and the desired wattage  409  may be specified to maintain a desired range of pulse rate of the rider. Other metrics that can be measured include the speed of the rider, the time the rider has been propelling the human powered vehicle  100  assuming they might get tired over time, and other metrics. 
     Assuming the current desired wattage  409  is to be changed, the control system  406  proceeds to box  466 . Otherwise, the control system  406  proceeds to box  475 . 
     In box  466 , the control system  406  increments, decrements, otherwise changes the desired wattage  409  based on the rider&#39;s input. Such an input may comprise, for example, pressing an arrow key that indicates that the desired wattage  409  should be increased or decreased by a predetermined amount, or a user input may simply specify a new value to be used for the desired wattage  409 . For example, over the course of a ride, the rider may want to increase/decrease the desired wattage value based on terrain, conditioning of the rider, to maintain a higher wattage output while increasing/decreasing velocity, and other factors. Thereafter, the control system proceeds to box  469 . 
     In box  469 , the control system  406  stores the current desired wattage  409  in the memory  403  so that the control system  406  can attempt to maintain the corresponding wattage value by adjusting the positioning of the magnets  126  placed within the adjustable magnet holding brackets  163  as mentioned above. 
     Next, the control system moves to box  472  in which the control system  406  determines whether to terminate based on user input or by virtue of the fact that the human powered vehicle  100   c  has stopped movement altogether for a predefined period of time. For example, the rider may have reached the intended destination and stopped propelling the human powered vehicle  100   c  and placed it in a storage space such as a garage or a bicycle rack. In another scenario, the rider may not want any added resistance during a segment of a ride and may terminate the control system  406  based on an interaction with a user interface on a display of the computing device  166 . Assuming that no circumstance exists such that the functionality of the control system  406  is to cease, the control system  406  proceeds to box  475 . Otherwise, the operation of the control system  406  ends as shown. 
     In box  475 , the control system  406  determines whether a selection of a wattage-per-distance record  415  has been made by a user. To this end, the computing device  166  may include various user interface components that allow a user to select a wattage-per-distance record  415  if desired. Such wattage-per-distance records may emulate the wattage that would need to be expended, for example, over a race course or a section of a long race such as a portion of the Tour de France as described above. If the rider chooses to select a file from the wattage-per-distance record, the control system proceeds to box  478 . If the rider does not choose to select a file from the wattage-per-distance record, the control system  406  reverts back to box  463 . Thus, the control system  406  remains in a loop at boxes  463  and  475  until a user manipulates the computing device  166  as described above. 
     In box  478 , the current distance traveled after a wattage-per-distance record  415  is selected is determined by the control system  406 . For example, the control system  406  can include a distance tracker that tracks the distance traveled by the human powered vehicle  100   c . In various embodiments, the control system  406  can incorporate a global positioning system (GPS) to track the distance traveled. The current distance traveled and the actual wattage readings received by the control system  406  over the current distance tracked can be compared to wattage values stored in a selected wattage-per-distance record  415 . For example, a selected wattage-per-distance record  415  includes wattage values to be maintained by the control system  406  as desired wattage  409  values at certain distance intervals. Once the current distance traveled by the human powered vehicle  100   c  meets a distance interval necessitating a wattage value change specified by the selected wattage-per-distance record  415 , the desired wattage  409  is automatically updated in the memory to the wattage value specified in the selected wattage-per-distance record  415 . 
     In an additional embodiment, the distance interval between desired wattages  409  in a given wattage-per-distance record  415  may be so small as to be effectively continuous. In such a manner, the control system  406  may examine the current value of the desired wattage from the wattage-per-distance record  415  each time the control system  406  reaches box  481 . In one embodiment, a delay may be imposed before the control system  406  reaches box  481  if it is desired to throttle the variation in the desired wattages  409  received from the wattage-per-distance record  415 . 
     Next, the control system  406  moves to box  481 . In box  481 , the control system determines whether to update the desired wattage  409  based on the wattage-per-distance record  415  selected and the current distance traveled by the human powered vehicle  100   c . As explained above, if the human powered vehicle  100   c  has traveled far enough to meet a next distance interval point necessitating a desired wattage  409  value change specified by the selected wattage-per-distance record  415 , the control system  406  moves to box  484 . If the human powered vehicle  100   c  has not yet traveled far enough, the control system  406  revers to box  478 . 
     In box  484 , the control system  406  updates the desired wattage value  409  in the memory  403  ( FIG.  12   ) to a current wattage value specified in the selected wattage-per-distance record  415 . For example, the wattage-per-distance record  415  selected may emulate a section of a race in which for the first 500 meters, the wattage to be maintained is 100 watts, and for the next 500 meters, the wattage to be maintained is 125 watts. As explained above, based on the current distance traveled that is determined in box  478 , if the human powered vehicle  100   c  has moved 500 meters, the control system  406  can update the desired wattage  409  in the memory  403  from 100 watts to 125 watts. To this end, the control system  406  will attempt to control the positioning of the magnets  126  placed in the adjustable magnet holding brackets  163  depending on the actual wattage readings received from the power meter  129  so that the total wattage consumed is as close as possible to the desired wattage  409  at any given time given that the terrain over which the human powered vehicle  100   c  may vary as well. 
     Next, the control system  406  proceeds to box  487 . In box  487 , the control system  406  can determine whether execution of the control system  406  is to be terminated based on user input or that the human powered vehicle  100   c  has reached a final destination point as specified by the selected wattage-per-distance record  415 , or based on some other criteria. For the case of user input, the rider may have reached the intended destination and stopped the human powered vehicle  100   c  from moving altogether. Alternatively, a termination condition may be that the human powered vehicle  100   c  has not moved for a predefined period of time. In another case, the rider may terminate the control system  406  prematurely before finishing out the segment specified in the wattage-per-distance record by manipulating elements of a user interface on the computing device  166 . If the control system  406  has not reached an ending point in box  487 , then the control system  406  reverts to box  478  as shown. Otherwise, the control system  406  ends as shown. 
     With reference to  FIG.  14   , shown is a flowchart that provides an example of the operation of an additional portion of the control system  406  according to various embodiments. To this end, the flowchart of  FIG.  14    exemplifies an adjustment process the control system  406  implemented to control the positioning of the magnets  126  ( FIGS.  7 - 11   ) based on the desired wattage  409  stored in the memory  403  at any given moment. It is understood that the flowchart of  FIG.  14    provides merely an example of the many different types of functional arrangements that may be employed to implement the operation of this portion of the control system  406  as described herein. As an alternative, the flowchart of  FIG.  14    may be viewed as depicting an example of elements of a method implemented in the computing device  166  ( FIG.  12   ) according to one or more embodiments. 
     Beginning with box  503 , the control system  406  obtains a current desired wattage  409  from the memory  403 . The desired wattage  409  may be manually entered by a user or taken from a wattage-per-distance record  415  as described above. 
     Next, the control system  406  proceeds to box  506  in which the control system  406  receives the actual wattage consumed from the power meter  129  ( FIG.  3   ) as the rider propels the human powered vehicle  100   c . The actual wattage value from the power meter  129  indicates an exertion level or total power expended by the rider as the human powered vehicle is moved. 
     Thereafter, the control system  406  proceeds to box  509  in which the control system  406  determines a differential between the current desired wattage  409  and the actual wattage being expended by the rider as the human powered vehicle  100   c  is propelled by the rider. In some scenarios, there may not be a differential if the rider is expending an actual wattage that is similar to the current desired wattage  409 . 
     Then, in box  512  the control system  406  determines whether an adjustment of the positioning of the magnets  126  is possible to match the actual wattage values to the desired wattage  409 . In some scenarios, the adjustable magnet holding bracket  163  can reach the maximum limit of its motion. That is to say, the control system  406  executed by the computing device  166  may move the magnets  126  to a position such that the magnets  126  are the farthest away from, or closest to, the conducting disc  116 . For example, during the course of a ride, the rider may transition from a flat terrain to a hilly terrain. When riding on the hilly terrain, it may not be possible to maintain the desired wattage  409  input by the rider as the actual wattage being expended could far exceed the desired wattage  409  even with the magnets  126  positioned as far away from the conducting disc  116  as possible. If in box  512  adjustment is not possible, the control system  406  proceeds to box  515 . If adjustment is possible, the control system  406  proceeds to box  518 . 
     In box  515 , the control system  406  notifies the rider that the adjustable magnet holding bracket  163  has reached the maximum limit of its motion. The rider can be notified by virtue of a banner or other output displayed on a user interface presented on a display of the computing device  166 . In other embodiments, the rider can be notified through a handheld device or a watch that is in wireless communication with the computing device  166 . The handheld device or watch can be communicatively coupled to the computing device  166  through WiFi, Bluetooth®, near-field communication (NFC), radio-frequency identification (RFID), wireless infrared, ultra-wideband, wireless induction, long range (LoRa), Z-Wave®, ZigBee®, and other wireless communication methods. Note that notification may also occur in some other manner such as haptic feedback on a watch or other device. After notifying the rider in box  515 , the control system  406  reverts back to box  503 . 
     Assuming the control system  406  proceeds to box  518 , the control system  406  adjusts the positioning of the magnets  126  so that the actual wattage consumed comes as close as possible to, or matches, the desired wattage  409 . In this manner, the control system  406  adjusts the positioning of the magnets  126  so as to minimize or eliminate any differential between the actual wattage consumed and the desired wattage  409 . 
     To achieve this, the control system  406  drives the one or more actuators  260  ( FIG.  8   ),  309  ( FIG.  10   ), or  366  ( FIG.  11   ) to adjust the positioning of the adjustable magnet holding brackets  163 . Alternatively, the control system  406  may adjust the power applied to the electromagnets  233  ( FIG.  7   ) accordingly. By adjusting the positioning of the magnet holding brackets  163   a - d , the positioning of the magnets  126  placed in the magnet holding brackets  163   a - d  can be moved closer to or further away from the conducting disc  116 . When the positioning of the magnets  126  are moved closer to the conducting disc  116 , the magnitude of the magnetic flux of the magnets  126  that intersect with conducting disc  116  increases. Conversely, as the one or more magnets  126  are moved away from a side of a given conducting disc  116 , the magnitude of the magnetic flux of the magnet  126  that intersects with the conducting disc  116  decreases. By adjusting the power applied to the electromagnets  233 , the magnitude of the magnetic flux that falls incident upon the conducting disc  116  is increased or decreased accordingly. 
     As a rider rides the human powered vehicle  100   c , the conducting discs  116  rotate, and eddy currents are induced in the conducting discs  116  by way of electromagnetic induction given that the magnetic fields of the magnets intersect with the conducting discs  116 . The eddy currents produce a counter electromagnetic field that opposes the magnetic field of the magnets  126 . As a result, the conducting discs  116  experience a drag force from the magnets  126  that opposes their rotation. The magnitude of the force that opposes the rotation of the conducting discs  116  depends on the size of the conducting disc  116 , the number of magnets or magnitude of the magnetic flux that intersects with the conducting disc  116 , the positioning of the magnets  126  relative to the conducting disc  116 , the rotational velocity of the conducting disc  116 , and on other factors. 
     Accordingly, the eddy currents produced on the conducting discs  116  oppose rotation of the wheels  103  and, correspondingly, increase the resistance experienced by a rider of the human powered vehicle  100   c , thereby making pedaling more difficult for the rider. 
     In box  521 , the control system  406  determines whether to terminate based on user input or by virtue of the fact that the human powered vehicle  100   c  has stopped movement altogether for a predefined period of time. For example, the rider may have reached the intended destination and stopped propelling the human powered vehicle  100   c  and placed it in a storage space such as a garage or a bicycle rack. In another scenario, the rider may not want any added resistance during a segment of a ride and may terminate the control system  406  based on an interaction with a user interface on a display of the computing device  166 . Assuming that no circumstance exists such that the functionality of the control system  406  is to cease, the control system  406  reverts back to box  503  as shown. Otherwise, the operation of the control system  406  ends as shown. 
     In another embodiment, a delay may be imposed between box  521  and box  503  that may vary depending on how large a differential is determined between the desired wattage and the actual wattage in box  509 . If the differential is greater, then such a delay may be reduced. Conversely, if the differential is smaller, then the delay may be increased. This would increase the responsiveness of the system when a larger differential is identified so that the system will react to cause the actual wattage to approach the desired wattage more quickly when needed. Stated another way, the frequency by which the control system  406  traverses the boxes of the flow chart of  FIG.  14    would increase or decrease accordingly. 
     It is understood that there may be other applications that are stored in the memory  403  and are executable by the processor  400  as can be appreciated. Where any component discussed herein is implemented in the form of software, any one of a number of programming languages may be employed such as, for example, C, C++, C#, Objective C, Java®, JavaScript®, Perl, PHP, Visual Basic®, Python®, Ruby, Flash®, or other programming languages. 
     A number of software components are stored in the memory  403  and are executable by the processor  400 . In this respect, the term “executable” means a program file that is in a form that can ultimately be run by the processor  400 . Examples of executable programs may be, for example, a compiled program that can be translated into machine code in a format that can be loaded into a random access portion of the memory  403  and run by the processor  400 , source code that may be expressed in proper format such as object code that is capable of being loaded into a random access portion of the memory  403  and executed by the processor  400 , or source code that may be interpreted by another executable program to generate instructions in a random access portion of the memory  403  to be executed by the processor  400 , etc. An executable program may be stored in any portion or component of the memory  403  including, for example, random access memory (RAM), read-only memory (ROM), hard drive, solid-state drive, USB flash drive, memory card, optical disc such as compact disc (CD) or digital versatile disc (DVD), floppy disk, magnetic tape, or other memory components. 
     The memory  403  is defined herein as including both volatile and nonvolatile memory and data storage components. Volatile components are those that do not retain data values upon loss of power. Nonvolatile components are those that retain data upon a loss of power. Thus, the memory  403  may comprise, for example, random access memory (RAM), read-only memory (ROM), hard disk drives, solid-state drives, USB flash drives, memory cards accessed via a memory card reader, floppy disks accessed via an associated floppy disk drive, optical discs accessed via an optical disc drive, magnetic tapes accessed via an appropriate tape drive, and/or other memory components, or a combination of any two or more of these memory components. In addition, the RAM may comprise, for example, static random access memory (SRAM), dynamic random access memory (DRAM), or magnetic random access memory (MRAM) and other such devices. The ROM may comprise, for example, a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or other like memory device. 
     Also, the processor  400  may represent multiple processors  400  and/or multiple processor cores and the memory  403  may represent multiple memories  403  that operate in parallel processing circuits, respectively. In such a case, the local interface  405  may be an appropriate network that facilitates communication between any two of the multiple processors  400 , between any processor  400  and any of the memories  403 , or between any two of the memories  403 , etc. The local interface  405  may comprise additional systems designed to coordinate this communication, including, for example, performing load balancing. The processor  400  may be of electrical or of some other available construction. 
     Although the control system  406  and other various systems described herein may be embodied in software or code executed by general purpose hardware as discussed above, as an alternative the same may also be embodied in dedicated hardware or a combination of software/general purpose hardware and dedicated hardware. If embodied in dedicated hardware, each can be implemented as a circuit or state machine that employs any one of or a combination of a number of technologies. These technologies may include, but are not limited to, discrete logic circuits having logic gates for implementing various logic functions upon an application of one or more data signals, application specific integrated circuits (ASICs) having appropriate logic gates, field-programmable gate arrays (FPGAs), or other components, etc. Such technologies are generally well known by those skilled in the art and, consequently, are not described in detail herein. 
     The flowcharts of  FIGS.  13  and  14    show the functionality and operation of an implementation of portions of the control system  406 . If embodied in software, each block may represent a module, segment, or portion of code that comprises program instructions to implement the specified logical function(s). The program instructions may be embodied in the form of source code that comprises human-readable statements written in a programming language or machine code that comprises numerical instructions recognizable by a suitable execution system such as the processor  400  in a computer system or other system. The machine code may be converted from the source code, etc. If embodied in hardware, each block may represent a circuit or a number of interconnected circuits to implement the specified logical function(s). 
     Although the flowcharts of  FIGS.  13  and  14    shows a specific order of execution, it is understood that the order of execution may differ from that which is depicted. For example, the order of execution of two or more blocks may be scrambled relative to the order shown. Also, two or more blocks shown in succession in  FIGS.  13  and  14    may be executed concurrently or with partial concurrence. Further, in some embodiments, one or more of the blocks shown in  FIGS.  13  and  14    may be skipped or omitted. In addition, any number of counters, state variables, warning semaphores, or messages might be added to the logical flow described herein, for purposes of enhanced utility, accounting, performance measurement, or providing troubleshooting aids, etc. It is understood that all such variations are within the scope of the present disclosure. 
     Also, any logic or application described herein, including the control system  406  that comprises software or code can be embodied in any non-transitory computer-readable medium for use by or in connection with an instruction execution system such as, for example, a processor  400  in a computer system or other system. In this sense, the logic may comprise, for example, statements including instructions and declarations that can be fetched from the computer-readable medium and executed by the instruction execution system. In the context of the present disclosure, a “computer-readable medium” can be any medium that can contain, store, or maintain the logic or application described herein for use by or in connection with the instruction execution system. 
     The computer-readable medium can comprise any one of many physical media such as, for example, magnetic, optical, or semiconductor media. More specific examples of a suitable computer-readable medium would include, but are not limited to, magnetic tapes, magnetic floppy diskettes, magnetic hard drives, memory cards, solid-state drives, USB flash drives, or optical discs. Also, the computer-readable medium may be a random access memory (RAM) including, for example, static random access memory (SRAM) and dynamic random access memory (DRAM), or magnetic random access memory (MRAM). In addition, the computer-readable medium may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or other type of memory device. 
     Disjunctive language, such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is to be understood with the context as used in general to present that an item, term, etc., can be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain embodiments require at least one of X, at least one of Y, or at least one of Z to be each present. 
     It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementations set forth for a clear understanding of the principles of the disclosure. Many variations and modifications can be made to the above-described embodiment(s) without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.