Patent Publication Number: US-2023145617-A1

Title: Control system of electric bicycle

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a control system of an electric bicycle. 
     Description of the Prior Art 
     With the popularity of sports, bicycles are not only used for transportation, but also an important item in leisure entertainments or sports competitions. Various types of bicycles have been developed, such as road bicycles, mountain bikes, electric bicycles and folding bikes, to meet different requirements, and some of the bicycles can be used with a bike trainer for riding training in a fixed location. 
     However, the use of a conventional bicycle is limited by weather, which is dangerous when the bicycle is ridden outdoor in bad weather. If the rider wants to ride a specific route (such as a hiking trail or any bike trail), the rider has to transport the bicycle to the destination first, which is inconvenient, wasting time and labor-consumption. In addition, a conventional electric bicycle with a bike trainer provides training effects by motors or magnetic resistance without consideration to weights of wheels and the rider, wind resistance, a friction between the wheel and the ground, a moment of inertia and other environmental factors in real riding, which results in a great difference in riding experience between simulated riding and real riding. 
     The present invention is, therefore, arisen to obviate or at least mitigate the above-mentioned disadvantages. 
     SUMMARY OF THE INVENTION 
     The main object of the present invention is to provide a control system of an electric bicycle, which provides a riding experience close to real riding and riding conditions adjustable to meet various requirements. 
     To achieve the above and other objects, the present invention provides a control system of an electric bicycle, including: a driving motor, a database and a control module. The driving motor includes a transmission module and at least one first sensor configured to sense at least one dynamic parameter of the transmission module, and the transmission module is configured to be co-movably connected with a driving mechanism of the electric bicycle. The database stores a plurality of riding mode information which respectively include a plurality of simulation parameters. The control module includes a setting unit, a computing unit communicated with the database and the setting unit, and a control unit communicated with the computing unit. The setting unit is configured to input at least one setting parameter, and the computing unit calculates a simulated moment of inertia and a calculation result data related to the simulated moment of inertia according to the at least one setting parameter, the at least one dynamic parameter and the plurality of simulation parameters. The computing unit outputs at least one control signal according to the calculation result data, and the control unit receives the at least one control signal and controls a driving state of the driving motor accordingly. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram showing arrangement of a preferable embodiment of the present invention; and 
         FIG.  2    is block diagram of a preferable embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIGS.  1  to  2    for a preferable embodiment of the present invention. A control system  1  of an electric bicycle  2  of the present invention includes a driving motor  10 , a database  20  and a control module  30 . 
     The driving motor  10  includes a transmission module  11  and at least one first sensor  12  configured to sense at least one dynamic parameter of the transmission module  11 , and the transmission module  11  is configured to be co-movably connected with a driving mechanism  201  of the electric bicycle  2 . The database  20  stores a plurality of riding mode information which respectively include a plurality of simulation parameters. The control module  30  includes a setting unit  31 , a computing unit  32  communicated with the database  20  and the setting unit  31 , and a control unit  33  communicated with the computing unit  32 . The setting unit  31  is configured to input at least one setting parameter, and the computing unit  32  calculates a simulated moment of inertia and a calculation result data related to the simulated moment of inertia according to the at least one setting parameter, the at least one dynamic parameter and the plurality of simulation parameters. The computing unit  32  outputs at least one control signal according to the calculation result data, and the control unit  33  receives the at least one control signal and controls a driving state of the driving motor  10  accordingly. Therefore, the control system  1  of the electric bicycle  2  can simulate an operation state of the electric bicycle  2  during being riding according to one of the plurality of riding mode information and control the driving motor  10  to provide resistance or assistance to the driving mechanism  201 , which provides a riding experience close to real riding and riding conditions adjustable to meet various requirements. 
     The at least one first sensor  12  includes at least one of a speed sensor and a torque sensor so as to sense driving force from the driving mechanism  201  to the driving motor  10  during riding so that the computing unit  32  can calculate integrally in real time. For example, the at least one first sensor  12  may be used to sense a pedaling frequency or a pedaling strength of the driving mechanism  201 . In this embodiment, the driving motor  10  is an external rotor permanent magnet synchronous motor assembled to a rear wheel  202  of the electric bicycle  2  by a standard quick-release mandrel, which is convenient to be assembled with a bike trainer  3  to ride the electric bicycle  2  in a fixed location. In this embodiment, the driving motor  10  is assembled to the rear wheel  202  and is co-movably connected with the driving mechanism  201 , and a moment of inertia of the rear wheel  202  is not considered during operation, which does not correspond to a real riding condition. Therefore, the control system  1  of the electric bicycle  2  has to consider a dimension of the rear wheel  202 , a weight of a rider, a weight of the electric bicycle  2  and other parameters to calculate the simulated moment of inertia so that the driving motor  10  can generate resistance or assistance to the driving mechanism  201  so as to realistically simulate various road conditions and provide various riding experience. In other embodiments, the driving motor may be disposed on a bottom bracket of the electric bicycle. 
     The plurality of riding mode information includes at least one of a cartographic information, a vehicle type information, a weather information and a training course information; the plurality of simulation parameters includes at least one of a distance data, a vehicle specification data, a route data and a slope data of the cartographic information, a wind resistance data and a simulated load data. The rider can select at least one of the plurality of riding mode information from the database  20  by the setting unit  31 , such as riding routes, types of the bicycle (mountain bike, road bike, folding bicycle, etc.) and weather conditions (strong wind, no wind, etc.), and the computing unit  32  instantly calculates resistance or assistance that the driving motor  10  should provide to the driving mechanism  201  at different time points accordingly so as to provide a riding experience as expected. The rider may select one of said training course information by the setting unit  31  and ride the electric bicycle  2  with the bike trainer  3  so that the electric bicycle  2  can be used as an exercise bike and provides different training effects. 
     Preferably, the control system  1  of the electric bicycle  2  further includes at least one second sensor  40  communicated with the computing unit  32 . The at least one second sensor  40  is configured to be disposed on the electric bicycle  2  and includes at least one of a cadence sensor, a torque sensor, a grade sensor, an attitude sensor and a tire pressure sensor. Therefore, when the rider is riding, the at least one second sensor  40  is configured to instantly sense a pedaling frequency of the rider, changes in force exerted by the rider on the driving mechanism  201 , friction between the wheel of the electric bicycle  2  and the ground, or an inertial force of the wheel, and the computing unit  32  can calculate gradient resistance of roads, the moment of inertia, rotation variations of the rear wheel  202 , friction resistance, or the like, which allows accurately integrate and estimate the torque that the driving motor  10  should provide. 
     Specifically, the computing unit  32  may calculate resistance or assistance that the driving motor  10  should provide under each of set conditions according to a relation (1) between a mass and a moment of inertia and a motor motion equation (2) as listed below: 
     
       
         
           
             
               
                 
                   
                     m 
                     × 
                     
                       
                         v 
                         2 
                       
                       
                         ω 
                         2 
                       
                     
                   
                   = 
                   I 
                 
               
               
                 
                   ( 
                   1 
                   ) 
                 
               
             
           
         
       
       
         
           
             
               
                 
                   T 
                   = 
                   
                     TL 
                     + 
                     
                       B 
                       ⁢ 
                       ω 
                     
                     + 
                     
                       J 
                       ⁢ 
                       
                         dw 
                         dt 
                       
                     
                   
                 
               
               
                 
                   
                     ( 
                     2 
                     ) 
                   
                 
               
             
           
         
       
     
     Wherein m is a sum of the weight of the rider and the weight of the electric bicycle  2  and is obtained from the setting unit  31  (inputted by the rider) or the database  20 ; v is a rate of the electric bicycle  2  which is obtained from the at least one first sensor  12 ; ω is an angular velocity of the rear wheel  202  and is obtained from the at least one first sensor  12 ; I is a moment of inertia of the rear wheel  202 ; TL is assistance or a resistance caused by the slope of the road and is obtained from the at least one second sensor  40  or the database  20 ; Bω may include at least one of a friction between the rear wheel  202  and the ground, wind resistance and other resistances from the environment and is obtained from the at least one second sensor  40  or the database  20 ; J is the simulated moment of inertia calculated from the equation (1); dw/dt is the rotation change of the rear wheel  202  and is obtained from the at least one first sensor  12  or the at least one second sensor  40 ; T is a torque required to be output by the driving motor  10  to drive the rear wheel  202 . Therefore, the control system  1  of the electric bicycle  2  actually considers the plurality of setting parameters, force exerted by the rider on the driving mechanism  201 , environmental resistances, friction between the electric bicycle  2  and the ground, the moment of inertia of the rear wheel  202  and other factors, and controls the driving motor  10  to apply resistance or assistance to the driving mechanism  201  accordingly so that the rider can have expected riding experience. 
     The control system  1  of the electric bicycle  2  further includes a power storage unit  50  electrically connected with the control unit  33 . The control unit  33  controls the power storage unit  50  to supply power to the driving motor  10  or controls the power storage unit  50  to store an electrical energy which is converted from a kinetic energy generated by the driving motor  10  so as to increase power supply for good durability of the electric bicycle  2 . The control system  1  of the electric bicycle  2  further includes a power consumption device  60  electrically connected with the control unit  33 . When an electric quantity of the power storage unit  50  is larger than or equal to a maximum electric quantity of the power storage unit  50  or when an instantaneous electric energy generated by the driving motor  10  is larger than a predetermined electric energy, the control unit  33  transmits an electric energy generated by the driving motor  10  to the power consumption device  60 , which protects the power storage unit  50  from electric overload due to excessive instantaneous electric energy and maintains an output resistance of the driving motor  10  so as to have good durability of the power storage unit  50 . For example, the power consumption device  60  may be connected with the control unit  33  by a conducting wire and includes at least one of a battery and an electro-thermal conversion device. The battery is configured to store excess electrical energy to increase the electrical quantity and charge external electronic devices, and the electro-thermal conversion device (such as a heat dissipation resistor, a fan, etc.) can release excess energy in the form of heat dissipation. The conduction relationship between the driving motor  10 , the power storage unit  50  and the power consumption device  60  may be controlled by electrical signals or mechanical switches. 
     Moreover, the setting unit  31  includes an electronic device  311 , and the electronic device  311  includes an operation display interface  312  which is configured to be operated externally and is communicated with the database  20  and the computing unit  32 . The electronic device  311  may be a phone, a tablet, a portable monitor, or the like and is configured to be assembled to a top tube or a stem of the electric bicycle  2  so as to be convenient to view and operate. The operation display interface  312  displays at least one of the at least one dynamic parameter, a riding data information, the electric quantity, the at least one setting parameter and one of the plurality of riding mode information which is set, so that the rider check at any time to confirm the setting and operation status of the electric bicycle  2 . The at least one setting parameter includes at least one of a weight of the rider, a weight of the electric bicycle  2  and a diametrical dimension of a wheel of the electric bicycle  2 . The at least one setting parameter can be input by the rider through the operation display interface  312  or be obtained from the default data in the database  20  for calculation. Preferably, the database  20  is a cloud database which is convenient to access and update. In other embodiments, the database may be a storage unit configured to be disposed on the electric bicycle. 
     In summary, the control system of the electric bicycle can provides a simulation of riding conditions according to the rider setting, and the computing unit can perform the integrated calculation of the actual riding conditions and the setting conditions of the rider, which provides a riding experience close to real riding and is adjustable to meet various requirements in the riding experience. In addition, the electric bicycle can be used in a fixed location or for mobile riding, which is not limited by weather conditions and is convenient to use. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.