System and method for electronically controlling resistance of an exercise machine
View Patent ↗A stationary exercise machine includes a system for electronically controlling a pedal resistance so as to simulate the riding of a road-going bicycle. The exercise machine includes a control system that monitors pedal velocity and that controls the resistive load generated by an electronically-controlled resistance mechanism. In one example, an electromagnetic device may vary a resistive load placed on a flywheel, which, in turn, varies the pedal resistance experienced by a user. When the user increases the pedal velocity, the resistance mechanism increases the resistive load. When the user decreases the pedal velocity, the resistance mechanism decreases the resistive load. In another example, the resistance mechanism varies the resistive load based on a gear selection by the user. The control system may also take into account other factors, such as the grade of the simulated ride, simulated wind resistance, or other frictional forces when calculating the resistive load.
1. A stationary bicycle capable of approximately simulating a pedal resistance felt by a rider of a multi-gear, road-going bicycle, the stationary bicycle comprising:
a flywheel;
a rotatable crank connected to the flywheel such that rotation of the crank translates into rotation of the flywheel;
pedals rotatably attached to the crank;
an electronically controlled resistance device configured to interact with the flywheel to apply a resistance to the flywheel, wherein the resistance is translated back to the pedals causing a user to exercise, the applied resistance comprising a dynamic resistive load component and a static resistive load component;
a display;
at least one sensor configured to monitor a pedal velocity of the pedals multiple times during a single revolution of the pedals, the at least one sensor being further configured to output a sensor signal indicative of a magnitude of a change in the pedal velocity between two of said multiple times during the single revolution of the pedals, the dynamic resistive load component of the applied resistance corresponding to the sensor signal;
a user input device configured to supply a resistance level selection of a user representing a selected bicycle gear, the static resistive load component of the applied resistance corresponding to the resistance level selection and being independent of the pedal velocity of the pedals; and
a processor configured to receive the resistance level selection and the sensor signal and to output one or more control signals causing the electronically controlled resistance device to apply more or less resistance based at least upon the resistance level selection and the magnitude of the change in the pedal velocity between two of said multiple times during the single revolution of the pedals.
2. The stationary bicycle of claim 1 , wherein the at least one sensor is configured to monitor the angular velocity of the flywheel.
3. The stationary bicycle of claim 1 , wherein the dynamic resistive load component of the applied resistance proportionally corresponds to the magnitude of the change in the pedal velocity.
4. A stationary bicycle capable of approximately simulating a pedal resistance felt by a rider of a road-going bicycle, the stationary bicycle comprising:
a flywheel;
a rotatable crank connected to the flywheel, wherein rotation of the crank translates into rotation of the flywheel;
pedals rotatably attached to the crank;
an electronically controlled resistance device configured to interact with the flywheel to apply a resistance to the flywheel, wherein the resistance is translated back to the pedals causing a user to exercise;
a user input device configured to supply a resistance level selection of a user, the resistance level selection representing a selected bicycle gear;
a sensor configured to output a first signal indicative of a first pedal velocity during a first time of a first revolution of the pedals and a second signal indicative of a second pedal velocity during a second time of the first revolution of the pedals; and
a processor configured to receive the first signal, the second signal, and the resistance level selection and to output one or more control signals causing the electronically controlled resistance device to apply more or less resistance based at least upon changes in the pedal velocity between the first and second times.
5. The stationary bicycle of claim 4 , wherein the processor is configured to output the one or more control signals causing the electronically controlled resistance device to apply additional resistance proportional to a magnitude of an increase in the pedal velocity.
6. The stationary bicycle of claim 4 , wherein the processor is configured to output the one or more control signals causing the electronically controlled resistance device to apply less resistance proportional to a magnitude of a decrease in the pedal velocity.
7. The stationary bicycle of claim 4 , wherein the processor is configured to output the one or more control signals causing the electronically controlled resistance device to apply resistance accounting for a simulated linear momentum of the stationary bicycle.
8. The stationary bicycle of claim 7 , wherein the simulated linear momentum accounts for an inputted mass of the user.
9. The stationary bicycle of claim 7 , wherein the simulated linear momentum accounts for the selected bicycle gear.
10. The stationary bicycle of claim 4 , wherein the processor is configured to output the one or more control signals causing the electronically controlled resistance device to apply resistance accounting for one or more simulated parasitic forces of the stationary bicycle.
11. The stationary bicycle of claim 4 , further comprising at least one controller board configured to receive the one or more control signals from the processor and configured to output one or more signals that cause the electronically controlled resistance device to apply more or less resistance to the flywheel.
12. A stationary bicycle capable of approximating a pedal resistance felt by a rider of a road-going bicycle, the stationary bicycle comprising:
means for receiving a user-applied force during the performance of a cycling exercise, wherein said means for receiving is configured to operate at a rotational velocity during said cycling exercise;
means for applying a resistive load that is translated to said means for receiving;
means for sensing said rotational velocity of said means for receiving multiple times during a single rotation of said means for receiving, wherein said means for sensing is configured to output a first signal indicative of said rotational velocity at a first time of said multiple times and a second signal indicative of said rotational velocity at a second time of said multiple times;
means for receiving from a user a selected gear and for supplying a third signal representing the selected gear; and
means for processing said first, second and third signals and for outputting one or more control signals causing said means for applying a resistive load to increase or decrease the resistive load based at least on said third signal and an increase or decrease in said rotational velocity between said first and second times.
13. The stationary bicycle of claim 1 , wherein the resistance applied to the flywheel is calculated according to the formula R=L+K(∂V/∂t), wherein R is the resistance applied to the flywheel, L is the static resistive load component, K is the resistance level selection and ∂V/∂t is the change in the pedal velocity over a period of time.
14. The stationary bicycle of claim 1 , wherein the dynamic resistive load component is zero when the pedal velocity of the pedals remains constant.
15. The stationary bicycle of claim 1 , wherein said multiple times correspond to approximately a one degree revolution of the pedals.
16. The stationary bicycle of claim 4 , wherein the applied resistive load comprises a static resistive load component and a dynamic resistive load component.
17. The stationary bicycle of claim 16 , wherein the static resistive load component is indicative of the resistance level selection.
18. The stationary bicycle of claim 16 , wherein the dynamic resistive load component is zero when the pedal velocity of the pedals remains constant.