Exercise device

• US 20070149364A1
• Filed: 12/22/2006
• Published: 06/28/2007
• Est. Priority Date: 12/22/2005
• Status: Active Grant

• Current Assignee: Scott B. Radow
• Original Assignee: Scott B. Radow
• Inventors: Blau, David, Radow, Scott
• Granted Patent: US 7,862,476 B2
• Time in Patent Office: Days
• US Class Current: 482/57
• CPC Class Codes: A63B 2022/0652 for cycling in a recumbent position
• CPC Class Codes: A63B 2024/009 the load of the exercise apparatus being controlled in synchronism with visualising systems, e.g. hill slope
• CPC Class Codes: A63B 2024/0093 the load of the exercise apparatus being controlled by performance parameters, e.g. distance or speed
• CPC Class Codes: A63B 21/0051 using eddy currents induced in moved elements, e.g. by permanent magnets
• CPC Class Codes: A63B 21/0053 using alternators or dynamos
• CPC Class Codes: A63B 21/0054 for charging a battery
• CPC Class Codes: A63B 21/0058 using motors
• CPC Class Codes: A63B 21/012 using frictional force-resisters electromagnetically-controlled brakes A63B21/0056
• CPC Class Codes: A63B 22/0076 Rowing machines for conditioning the cardio-vascular system seats moving during exercise A63B22/0087; training appliances for rowing or sculling on boats A63B69/06
• CPC Class Codes: A63B 22/0605 performing a circular movement, e.g. ergometers
• CPC Class Codes: A63B 2220/30 Speed
• CPC Class Codes: A63B 2220/51 Force
• CPC Class Codes: A63B 2220/54 Torque
• CPC Class Codes: A63B 2220/58 Measurement of force related parameters by electric or magnetic means
• CPC Class Codes: A63B 24/00 Electric or electronic controls for exercising apparatus of preceding groups; Controlling or monitoring of exercises, sportive games, training or athletic performances
• CPC Class Codes: A63B 24/0087 Electric or electronic controls for exercising apparatus of groups A63B21/00 - A63B23/00, e.g. controlling load
• CPC Class Codes: A63B 69/10 Swimming instruction apparatus for use without water
• CPC Class Codes: A63F 2300/1037 being specially adapted for converting control signals received from the game device into a haptic signal, e.g. using force feedback
• CPC Class Codes: A63F 2300/1062 being specially adapted to a type of game, e.g. steering wheel
• CPC Class Codes: A63F 2300/8005 Athletics

Abstract

A control system and method for exercise equipment and the like provides a way to simulate a physical activity in a manner that takes into account the physics of the physical activity being simulated to provide an accurate simulation. According to one aspect of the present invention, the control system and method takes into account the physics of the corresponding physical activity to generate a virtual or predicted value of a variable such as velocity, acceleration, force, or the like. The difference between the virtual or expected physical variable and a measured variable is used as a control input to control resistance forces of the exercise equipment in a way that causes the user to experience forces that are the same or similar to the forces that would be encountered if the user were actually performing the physical activity being simulated rather than using the exercise equipment.

Claims

1. A stationary bike, comprising:

a support structure defining a front portion and a rear portion;

a seat mounted to the support structure;

a crank rotatably mounted to the support structure for rotation about an axis, the crank including a pair of pedals that are movable along a generally circular path about the axis, the circular path defining a forward portion in front of the axis and a rear portion in back of the axis;

a control system including a force-generating device connected to the crank to vary a resistance force experienced by a user pedaling the stationary bike, wherein the controller controls the force-generating device and causes the resistance force experienced by a user to be greater in the forward portion of the circular path than in the rear portion of the path.

2. The stationary bike of claim 1, wherein:

the force-generating device comprises a mechanical brake.

3. The stationary bike of claim 1, wherein;

the force-generating device comprises an electrical-based device that does not utilize variation in frictional forces generated by contact between two parts that are moving relative to one another to vary the resistance force.

4. The stationary bike of claim 3, wherein:

the force-generating device comprises an alternator.

5. The stationary bike of claim 4, including:

an electrical control operably connected to the alternator, wherein the electrical control causes the alternator to generate a resistance torque that is sufficiently constant to substantially eliminate perceptible resistance force variations at the pedals.

6. The stationary bike of claim 4, wherein:

the alternator includes at least three stator windings; and

including;

an electrical control that causes the three stator windings to be loaded simultaneously such that all three stator windings simultaneously generate appreciable electrical current.

7. The stationary bike of claim 6, wherein:

the electrical control varies the field current to control the force produced by the alternator.

8. The stationary bike of claim 7, wherein:

each stator winding is electrically connected to the other stator windings across a resistor.

9. The stationary bike of claim 8, wherein:

the circuit includes a switch connected in series with each resistor.

10. The stationary bike of claim 9, including:

a battery; and

wherein;

the switches are opened for a plurality of short time periods to change the battery.

11. The stationary bike of claim 10, wherein:

the time periods are sufficiently short so as to avoid generating a force variation that can be perceived by a user.

12. The stationary bike of claim 10, wherein:

the time periods are sufficiently short so as to prevent large changes in current through coils of the alternator.

13. The stationary bike of claim 1, wherein:

the control system utilizes a measured value of a user'"'"'s input to the stationary bike to control the resistance force.

14. The stationary bike of claim 1, wherein:

the control system determines at least one virtual property and utilizes a difference between the virtual property and a corresponding measured property to determine a control input to control the resistance force experienced by a user.

15. The stationary bike of claim 14, wherein:

the virtual property comprises a virtual velocity.

16. The stationary bike of claim 15, wherein:

the measured property comprises the rotation rate of the pedals.

17. The stationary bike of claim 1, wherein:

the control system utilizes at least a portion of an equation of motion of a bicycle to determine a virtual variable, wherein the virtual variable is selected from a group consisting of a virtual rider applied force, a virtual velocity, and a virtual acceleration.

18. The stationary bike of claim 17, wherein:

the stationary bike includes a sensor capable of measuring a real variable, wherein the real variable is selected from a group consisting of a force applied to the pedals by a user, a crank velocity, and an acceleration of the crank.

19. The stationary bike of claim 18, wherein:

the control system utilizes the difference between the virtual variable and the real variable to control the resistance force.

20. The stationary bike of claim 1, wherein:

the control system determines a virtual velocity utilizing a calculated aerodynamic drag factor that varies non-linearly as a function of the virtual velocity.

21. The stationary bike of claim 20, wherein:

the aerodynamic drag factor is proportional to the virtual velocity squared.

22. The stationary bike of claim 1, wherein:

the control system controls the force-generating device such that a larger force is generated if the rider'"'"'s pedaling rate is increased relative to a constant pedaling rate.

23. The stationary bike of claim 1, wherein:

the stationary bike defines a velocity that is a function of the pedal r.p.m., and wherein the control system provides a steady-state resistance force that must be provided by a rider to maintain a constant r.p.m., and wherein the steady-state resistance force increases as the pedal r.p.m. increases and the controller is simulating riding on a non-sloped surface.

24. The stationary bike of claim 1, wherein:

the controller causes the force-generating device to provide resistance forces for a user that vary according to the acceleration that would be experienced by a user riding an actual bicycle.

25. The stationary bike of claim 1, wherein:

the controller generates a pedal force after a coasting period by a user during which the pedals are not rotated that is substantially similar to a pedaling force that would be experienced by a rider of an actual bicycle after the same coasting period.

26. The stationary bike of claim 1, wherein:

each pedal defines a top pedal position wherein the pedal is directly above the axis, and a bottom position wherein the pedal is directly below the axis, and wherein the control causes the resistance force to be substantially lower when the pedals are in the vicinity of the top and bottom positions than when the pedals are in other positions on the circular path.

27. The stationary bike of claim 1, wherein:

the resistance force varies periodically twice during each revolution of the crank.

28. The stationary bike of claim 1, wherein:

the resistance force as a function of time is approximately sinusoidal.

29. The stationary bike of claim 28, wherein:

a plot of the shape of the resistance force as a function of time is not identical during each crank revolution.

30. The stationary bike of claim 29, wherein:

the resistance force as a function of time is not determined according to a predetermined mathematical relationship utilizing pedal position.

31. The stationary bike of claim 1, wherein:

the resistance force is determined by taking into account at least one factor relating to an equation of motion for a bicycle.

32. A stationary bike that substantially simulates the pedaling effort of a moving bicycle, the stationary bike comprising:

a support structure;

a pedal structure movably mounted to the support structure;

the pedal structure including two pedals that move about an axis to define an angular velocity, and wherein forces applied to the pedals by a user define user input forces;

a controller operably connected to the pedal structure to provide a variable resistance force restraining movement of the pedals in response to user input forces, wherein the variable resistance force substantially emulates at least some of the effects of inertia that would be experienced by a rider of a moving bicycle.

33. The stationary bike of claim 32, wherein:

the controller provides a variable resistance force that accounts for aerodynamic drag.

34. The stationary bike of claim 33, wherein:

the controller determines a bike velocity and utilizes the velocity to determine an aerodynamic drag factor that increases with velocity, and wherein the variable resistance force is determined, at least in part, by taking into account the aerodynamic drag factor.

35. The stationary bike of claim 34, wherein:

the aerodynamic drag factor increases as a function of the square of the bike velocity.

36. The stationary bike of claim 35, wherein:

the bike velocity comprises a virtual bike velocity that is different than a measured bike velocity determined from the angular velocity of the pedals.

37. The stationary bike of claim 32, wherein:

the controller utilizes at least a portion of an equation of motion for a moving bicycle to provide the variable resistance force.

38. The stationary bike of claim 37, wherein:

the equation of motion includes at least one of an aerodynamic drag factor, a slope factor, and a momentum factor.

39. The stationary bike of claim 38, wherein:

the controller determines a virtual velocity based, at least in part, on the equation of motion, and wherein;

the controller utilizes a difference between a measured velocity related to the angular velocity of the pedals and the virtual velocity to determine the variable resistance force.

40. The stationary bike of claim 39, wherein:

in use, a user generates a user input power to the stationary bike;

the controller utilizes an estimate of the user input power to determine an estimate of the user input forces to determine the virtual velocity.

41. The stationary bike of claim 39, wherein:

the stationary bike includes a force sensor that measures applied forces of a user; and

wherein;

the controller utilizes force data from the force sensor to determine the virtual velocity.

42. The stationary bike of claim 32, wherein:

the stationary bike includes an alternator operably connected to the pedal structure to provide variable resistance forces in response to control information from the controller.

43. The stationary bike of claim 32, wherein:

the stationary bike includes a mechanical brake operably connected to the pedal structure to provide variable resistance forces in response to control information from the controller.

44. The stationary bike of claim 32, wherein:

the controller includes a road bike model that takes into account mathematically the factors that would affect a user of the stationary bike if the user were riding a movable bicycle and providing the user input forces to the movable bicycle.

45. The stationary bike of claim 44, wherein:

the road bike model includes an aerodynamic drag factor and a momentum factor.

46. The stationary bike of claim 45, wherein:

the road bike model includes a slope factor.

47. The stationary bike of claim 46, wherein:

the road bike model includes a friction factor.

48. The stationary bike of claim 46, wherein:

the road bike model utilizes a measured value relating to the operation conditions of the stationary bike and sums the effects of the aerodynamic drag factor, the momentum factor, and the slope factor to determine a virtual velocity, and wherein;

the controller utilizes a velocity difference between the virtual velocity and a measured velocity corresponding to the angular velocity of the pedal structure as an input to determine the variable resistance force.

49. The stationary bike of claim 48, wherein:

the variable resistance force increases linearly as the velocity difference increases.

50. The stationary bike of claim 32, wherein:

the controller includes an electronic memory that stores information concerning the road bike model.

51. The stationary bike of claim 32, wherein:

the pedal structure is rotatably mounted to the support structure, and the pedals move in a circular path.

52. The stationary bike of claim 32, wherein:

the controller includes input features that permit the controller to account for the physical characteristics of an individual user in providing the variable resistance force.

53. The stationary bike of claim 52, wherein:

the controller utilizes a rider weight input to determine a slope factor that simulates riding a bicycle on a hill, such that the variable resistance force is different upon entry of different rider weight inputs.

54. The stationary bike of claim 52, wherein:

the controller utilizes an input to calculate an aerodynamic drag factor that affects the variable resistance force as a user'"'"'s speed changes.

55. The stationary bike of claim 32, wherein:

the pedals move in a cyclical manner and move 360°

per cycle;

the variable resistance force includes a component that varies periodically during each pedal cycle.

56. The stationary bike of claim 55, wherein:

the variable resistance force includes a component that simulates the effects of momentum that effect the resistance force experienced by a rider of a movable bike.

57. The stationary bike of claim 55, wherein:

the variable resistance force includes a component that simulates the effects of aerodynamic drag.

58. The stationary bike of claim 55, wherein:

the variable resistance force includes a component that simulates the effects of a slope.

59. The stationary bike of claim 32, including:

an encoder providing information concerning the position of the pedals to the controller.

60. The stationary bike of claim 32, wherein:

the controller includes a gear rollout to determine a velocity from the angular velocity of the pedals.

61. The stationary bike of claim 60, wherein:

the controller changes the gear rollout based on a user input.

62. The stationary bike of claim 61, wherein:

the stationary bike includes a gear selector input feature that a user can utilize to change the gear rollout.

63. An exercise device, comprising:

a support structure;

a user interaction member movably connected to the support structure for movement relative to the support structure in response to application of a force to the user interaction member by a user;

an alternator of the type having a plurality of stator rails and a rotor that is movable to cause an electric current in the stator coils, wherein the alternator is operably connected to the user interaction member, and wherein the alternator provides a variable force tending to resist movement of the user interaction member relative to the support structure, and wherein the variable force varies according to variations of a field current applied to the rotor, and wherein the variable force is substantially free of undulations related to voltage ripple.

64. The exercise device of claim 63, wherein:

the alternator includes at least three stator coils, and wherein each stator coil is electrically connected to the other stator coils across a resistor.

65. The exercise device of claim 64, including:

a switch connected in series with each resistor.

66. The exercise device of claim 65, including:

a battery; and

wherein;

each stator coil is electrically connected to the battery, and the switches are selectively controlled to electrically charge the battery.

67. The exercise device of claim 66, wherein:

the switches are opened for sufficiently short periods of time so as to prevent a significant change in current flow through the stator coils.

68. The exercise device of claim 66, wherein:

the switches are opened and closed in a manner that does not produce a torque variation that can be readily perceived by a user of the exercise device.

69. The exercise device of claim 63, including:

an alternator control circuit connected to the alternator, wherein the circuit is configured to provide a load power factor of one.

70. The exercise device of claim 63, including:

an alternator control circuit connected to the alternator, wherein the circuit is configured to provide a load power factor that is greater than the inverse of the square root of three.

71. The exercise device of claim 70, wherein:

the circuit is configured to provide a load power factor that is substantially greater than the inverse of the square root of three.

72. The exercise device of claim 63, including:

an alternator control that utilizes changes in the field current to change the variable force, and wherein the variable force changes substantially within about one millisecond or less of a change in the field current.

73. An exercise device for simulating a physical activity, comprising:

a structural support;

a user input member movably connected to the structural support for movement relative to the structural support upon application of a force to the input member by a user, and wherein the user input member defines a variable resistance force tending to resist movement due to force applied by a user;

a control system that utilizes a velocity difference between a measured velocity and a virtual velocity as a control input to control the resistance force on the user input member, wherein the virtual velocity is determined by at least partially modeling, the physical activity being simulated.

74. The exercise device of claim 73, wherein:

the control system includes a sensor that measures a variable associated with movement and the user input member from which a velocity of the user input member can be determined.

75. The exercise device of claim 74, wherein:

the control system includes a force-generating device that supplies the variable resistance force.

76. The exercise device of claim 75, wherein:

the force-generating device comprises an alternator.

77. The exercise device of claim 76, wherein:

the alternator is controlled in such a way that the alternator is substantially free of torque ripple.

78. The exercise device of claim 75, wherein:

the control system includes a controller connected to the sensor and the force-generating device and sending a signal to the force-generating device based, at least in part, on a signal from the sensor.

79. The exercise device of claim 78, wherein:

the controller determines an estimated user power, and utilizes the estimated user power to determine the measured velocity.

80. The exercise device of claim 78, wherein:

the controller updates the virtual velocity in a manner that takes into account the effects of momentum.

81. The exercise device of claim 80, wherein:

the controller utilizes a linear relationship between acceleration and force to determine the effects of momentum.

82. The exercise device of claim 80, wherein:

the controller updates the virtual velocity by summing the effects of aerodynamic drag and momentum.

83. The exercise device of claim 82, wherein:

the controller updates the virtual velocity by taking into account a slope of a virtual hill.

84. The exercise device of claim 83, wherein:

the controller updates the virtual velocity by taking into account the effects of friction losses.

85. The exercise device of claim 83, wherein:

the exercise device comprises a stationary bike, and the user input member comprises a crank having a pair of pedals that move in a generally circular path about an axis.

86. The exercise device of claim 85, wherein:

the controller includes a mathematical model of bike that takes into account the physics associated with riding a moving bike, and wherein the mathematical mode is utilized to calculate the virtual velocity.

87. The exercise device of claim 86, wherein:

the mathematical model includes a plurality of gear ratios, and wherein the controller includes a user input feature that enables a user to select and change gears.

88. The exercise device of claim 86, wherein:

the controller includes a user input feature that permits a user to select a weight used in the mathematical model.

89. The exercise device of claim 73, wherein:

the control system utilizes a measured force to determine the virtual velocity.

90. The exercise device of claim 73, wherein:

the control system is configured to vary the resistance force in a manner that tends to minimize the velocity difference.

91. The exercise device of claim 73, wherein:

the control system is configured to vary the resistance force in a manner that drives the velocity difference to a predetermined value, and wherein the rider force determined by the summing is utilized to determine a virtual acceleration by dividing the rider force by a rider mass.

92. A stationary exercise bike, comprising:

a support structure;

a crank including a pair of pedals rotatably mounted to the support structure;

a force-generating device operably connected to the crank and providing a variable resistance force tending to resist a force applied to the pedals by a user;

a sensor configured to measure a variable associated with the crank during operation from which an actual velocity can be determined;

an electrical control unit connected to the sensor and the alternator, therein the electrical control unit includes an internal bike model that is utilized to determine a virtual velocity of the internal bike model, and wherein the internal bike model utilizes the measured variable as an input to the internal bike model, and wherein the internal bike model determines an updated virtual velocity from a prior virtual velocity stored in the electrical control unit by determining a rider force by summing at least the effects of the measured variable, an aerodynamic loss determined utilizing the prior virtual velocity, and an effect due to a hill angle determined according to a weight and a slope of a virtual hill, and wherein the virtual acceleration is integrated to provide the virtual velocity, and wherein;

the controller utilizes a velocity difference between the actual velocity and the virtual velocity and the virtual velocity as a control input, and increases the variable resistance force of the force-generating device in a manner that tends to reduce the velocity difference.

93. The stationary bike of claim 92, wherein:

the sensor comprises a force sensor, and the measured variable comprises a rider force.

94. The stationary bike of claim 93, wherein:

the rider force is modified prior to input to the internal bike model by dividing the rider force by a gear rollout.

95. The stationary bike of claim 94, wherein:

the stationary bike includes a gear selection feature enabling a user to select the gear rollout.

96. The stationary bike of claim 92, wherein:

the measured variable is related to a power input to the stationary bike by a user; and

wherein;

the controller determines the power input by a user and determines an estimated rider force by dividing the power input by a user by a prior virtual velocity, and wherein the estimated rider force is utilized as the measured variable that is input to the internal bike model.

97. The stationary bike of claim 92, wherein:

the force-generating device comprises an alternator.

98. The stationary bike of claim 97, wherein:

the alternator is connected to the crank by an elongated flexible member having the form of a loop.