METHOD FOR CONTROLLING A POWERTRAIN UNIT, POWERTRAIN UNIT AND PEDAL VEHICLE

Description

BE2025 / 5061 -2- • An output body driven in rotation by the output element of the differential system, • A free wheel between the output element of the differential system and a rear wheel of the pedal vehicle, the free wheel is capable of coupling or uncoupling the rear wheel and the crankset, 5 the process comprising • An interruption of pedaling then a resumption of pedaling by the cyclist, • A calculation of a first speed at a defined point of the drive system, downstream of the differential system, as a function of the speed of the first 10 motor and the second motor, • A calculation of a second speed at a defined point of the drive system as a function of a measurement of the vehicle's speed, • A calculation of a difference between the first speed and the second speed, 15 • Control of the first motor by the control unit, the control unit controlling the first motor's speed, • Control of the second motor by the control unit when the difference between the first and second speeds is above a certain threshold,The control of the second motor compensating for the inertia of at least part of the powertrain, • Control of the second motor by the control unit with a torque setpoint corresponding to the assistance level only when the difference between first and second gear is below a certain threshold. 25 According to one variant, the control of the second motor is by torque, the method comprising the determination of the rotational acceleration of at least certain components of the powertrain, and the determination of the torque to be applied to the second motor compensating for the inertia of at least part of the powertrain. 30 2025 / 5061 BE2025 / 5061 -3- According to one variant, the torque setpoint applied to the second motor is different from the torque corresponding to the setpoint assistance level. According to one variant, the powertrain comprises a first freewheel between the pedal assembly and the second input element, a process in which control of the second motor is in speed and comprising 5 - The determination of the speed of the input body,-The determination of the speed to be applied to the second motor such that the speed downstream of the first free wheel is greater than the speed upstream of the first free wheel, the free wheel decoupling the pedal assembly and the second input element, 10 the inertia of at least part of the powertrain downstream of the free wheel is compensated by the first motor and / or the second motor. According to one variant, the control of the first motor is in position or in speed. According to another variant, the control of the first motor is adapted to accelerate 15 the zeroing of the difference between the first speed and the second speed. According to another variant, the control of the first motor is in position or in speed so as to impose a continuously differentiable speed upstream of the free wheel during the synchronization of the free wheel. According to one variant, the first motor is controlled at a setpoint speed 20 such that the speed upstream of the free wheel is less than the speed downstream of the free wheel, the speed upstream of the free wheel being less than a speed difference such that the free wheel is decoupled. According to another variant,the control of the first motor is in speed with a higher speed setpoint value than the target speed setpoint value 25. According to one variant, the method further comprises a step of controlling the first motor during the interruption of pedaling and before the resumption of pedaling by the cyclist, the control of the first motor being in position or speed so as to accelerate the zeroing of the difference between the first gear and the second gear upon resumption of pedaling, and / or so as to impose a continuously differentiable speed upstream of the free wheel during the synchronization of the free wheel upon resumption of pedaling, and / or such that the speed upstream of the free wheel is lower than the speed downstream of the free wheel upon resumption of pedaling, the speed upstream of the free wheel being lower than a speed difference such that the free wheel is decoupled. According to one variant, the second speed is calculated by the control unit using one or more wheel sensors. According to another variant,The vehicle's first speed is calculated by the control unit based on the rotational speeds of the first and second motors. According to one variant, resuming pedaling corresponds to the moment when the cyclist again applies force to the pedals. According to another variant, the difference between first and second speed indicates the state of engagement or disengagement of the freewheel. According to another variant, the second motor is connected to the second input element of the differential system or to the output element of the differential system. According to another variant, the pedals are connected to the second input element. The invention also relates to a powertrain for a pedal vehicle, the powertrain being capable of implementing the method as described above. 20 The invention also relates to a pedal vehicle, comprising a propulsion assembly including the powertrain as described above. According to one embodiment, the vehicle further comprises a pedal assembly, the geared motor assembly being located at the pedal assembly. 25 According to one embodiment, the vehicle comprises a rear wheel,The geared motor group is located at the rear wheel's axis of rotation. Within the scope of this document, the successive indication of process steps does not necessarily mean that the steps occur one after the other, but possibly in parallel. 30 2025 / 5061 BE2025 / 5061 -5- Within the scope of this document, two connected or linked elements may be connected or linked directly or indirectly. They may, for example, be directly or indirectly meshed via at least one intermediate gear, a belt, and / or a roller. In the context of this document, the terms "input" and "output" 5 should be understood as an input and an output in a kinematic chain, namely the propulsion system. An input is preferably a mechanical power input, and an output is preferably a mechanical power output. In the context of this document, a gear element can, for example, be a gear or a plurality of gears mechanically coupled or meshed together. In the context of this document,An element "arranged so as to rotate about an axis of rotation" is preferably an element essentially symmetric about that axis.15 In the context of this document, a "fixed ratio" between two objects or elements means that their rotational speeds are in a constant ratio. In this document, the "powertrain speed ratio" refers to the speed ratio between an output body and an input body. In this document, the "powertrain assistance level" refers to the proportion of power provided by the electric assist relative to the power provided by the rider. It can be calculated as the combined power of both motors divided by the sum of the combined power of both motors and the rider's power. It can also be called the "assistance level parameter." This is a parameter that can be manually controlled by the rider via a control interface or calculated automatically by the control unit based on other parameters. In this document,An angular position measurement is equivalent to an angular velocity measurement. Indeed, the powertrain group 30 preferably includes a means for determining the angular velocity of one of the 2025 / 5061 BE2025 / 5061 -6- engines from the angular position of that engine (or any rotating part). There is no fundamental difference between a position control and a velocity control because there is a direct mathematical relationship between the two values. Angular velocity is the time derivative of angular position. For example, controlling a motor to rotate at a constant angular velocity is equivalent to controlling a motor to maintain an angular position that evolves linearly over time. The same applies to measuring the angular acceleration of any rotating component, since there is also a direct mathematical relationship with angular position or velocity – acceleration being the time derivative of velocity.10 In the context of this document, a current measurement is equivalent to a torque measurement. More specifically,A measurement of the current in the phases of an engine is equivalent to a measurement of torque. Indeed, the powertrain preferably includes a means for determining the torque of one of the engines from the current supplied to that engine.15 In the context of this document, the terms "upstream" and "downstream" should be understood to mean that an upstream element is closer to the power source and a downstream element is closer to an output driven element. The use, in this document, of the verb "include", its variants, as well as its conjugations, cannot in any way exclude the presence of elements20 other than those mentioned. The use, in this document, of the indefinite article "a", "an", or the definite article "the", "the", or "an" to introduce an element does not exclude the presence of a plurality of these elements. The terms "first", "second", "third", etc., are used in this document exclusively to differentiate between different elements.without implying any order between these elements. The set of preferred embodiments, as well as all the advantages of the powertrain control method according to the invention, are transposed mutatis mutandis to the present powertrain and vehicle, and vice versa. The different embodiments can be considered alone or in combination. 2025 / 5061 BE2025 / 5061 -7- Brief description of the figures Other features and advantages of the present invention will become apparent from the detailed description that follows, for the understanding of which reference should be made to the attached figures which show: - Figure 1, an example of a functional view of a powertrain in which the method is implemented; - Figure 2, a detailed functional view of Figure 1; - Figure 3, another detailed functional view of Figure 1. The drawings of the figures are not to scale. Similar features are generally denoted by similar reference numerals in the figures. Within the framework of this document,Identical or analogous elements may bear the same references. Furthermore, the presence of reference numbers or letters to the drawings cannot be considered limiting, including when such numbers or letters are indicated in the claims. Detailed description of embodiments of the invention 15 The invention relates to a method for controlling a powertrain of a pedal vehicle propulsion system, the system comprising a first motor and a second motor, the second motor being an assistance regulation motor. The method includes in particular a step of interrupting pedaling and then resuming pedaling by a user, a 20 step of calculating a first speed at a defined point of the propulsion system, downstream of the differential system, as a function of the speed of the first motor and the second motor, a step of calculating a second speed at the defined point of the propulsion system as a function of a measurement of the vehicle's speed, a step of calculating a difference between the first speed and the 25 second speed,The process includes a control step of the first motor of the powertrain by a control unit, the control unit controlling the first motor's speed. The process also includes a control step of the second motor by the control unit when the difference between first and second gear is above a certain threshold, the control of the second motor compensating for at least the inertia of at least part of the powertrain, and a control step of the second motor by the control unit with a torque command corresponding to the assistance level only when the difference between first and second gear is below a certain threshold. This allows for a smooth resumption of pedaling and enables the desired gear ratio to be reached as smoothly as possible. The method according to the invention differs from the prior art and in particular from document WO2013 / 160477 (or US2015122565) because the method implements a calculation of several speeds (based on other criteria) at the same point, 10 called the defined point. In the prior art,The definition of such a point is not provided. The method also targets a particular moment in the use of the pedal vehicle, namely the resumption of pedaling. The control method provides for carrying out the resumption of pedaling in two phases. The method provides for delaying, in a first phase (or transitional phase), the application of a torque corresponding to the level of assistance required by the user, before applying, in a second phase, the torque corresponding to the required level of assistance. During the first phase, the second motor is not controlled with the torque setting corresponding to the level of assistance required by the user, even though the user has requested a level of assistance. In other words, during the first phase,The second motor is controlled with a torque setting different from that corresponding to the level of assistance actually required by the user. It is only in the second phase that the second motor is controlled with the torque setting corresponding to the level of assistance required by the user. Thus, the invention does not aim at a generic control of two motors but at a two-phase resumption of pedaling allowing a pleasant resumption of pedaling and the achievement of the desired speed ratio in the smoothest possible manner. Resumption of pedaling corresponds to the moment when the cyclist again applies action to a crankset21 – in particular the pedals – while having30 the vehicle in motion. Resumption of pedaling begins a transitional phase which 2025 / 5061 BE2025 / 5061 -9- will have the effect of resynchronizing (or in other words,(decouple) the crankset and one of the rear wheels. Figure 1 is an example of a functional view of a drive assembly 2 in which the process is implemented. The drive assembly 2 is applied to a pedal-powered vehicle. The drive assembly 2 is schematically represented between a cyclist 5(C) and a rear wheel 16 (with an angular velocity ωW). The pedal-powered vehicle can, for example, be a bicycle, a tricycle, or other. In particular, it concerns bicycles, tricycles, or other electrically assisted vehicles. The drive assembly 2 includes the crankset 21 (including pedals) operated by the cyclist 5. The crankset allows the cyclist to propel the vehicle with or without the assistance regulation 10 of electric motors described later. The drive assembly 2 includes a powertrain 1(DU) which can be located at the level of the pedal assembly 21 (mid-drive type drive unit 2). The drive unit 1 may be located in other positions. For example, the drive unit 1 may be located in the hub of a rear wheel 16 of the vehicle 15 (hub-drive type drive unit). In other cases,For example, in two-wheeled cargo vehicles, tricycles, or quadricycles, the powertrain 1 may be located between the crankset and the rear axle of the vehicle. The powertrain 1 may include an input body 11 and an output body 13. The crankset 21 may be identical to the input body 11 of the powertrain 1. Alternatively, the output body 13 may be identical to the wheel rim 16. The drive assembly 2 may include an upstream transmission 18 between the crankset 21 and the input body 11 of the powertrain 1. The upstream transmission 18 connects the crankset 21 and the input body 11 together. The upstream transmission 18 may be a chain,A belt or any type of transmission element. The upstream transmission can modify the angular velocity ωCK of the crankset (or crankshaft) into an angular velocity ωI. The upstream transmission 18 may be optional. The drive assembly 2 may include a downstream transmission 20 (All) 30 between the output body 13 of the drive assembly 1 and one or more rear wheels 2025 / 5061 BE2025 / 5061 -10- 16 of the vehicle. The downstream transmission 20 connects the output body 13 and one or more rear wheels 16. The downstream transmission can modify the angular velocity ωO of the output body 13 into an angular velocity ωTO. The downstream transmission 20 may be optional. Thus, in the "middrive" type propulsion assembly 2 of a vehicle with a powertrain 5 located at the pedal assembly 21, the pedal assembly 21 can be confused with the input shaft 11 (and therefore the upstream transmission 18 is absent) and the downstream transmission 20 can be a chain or a belt connecting the output shaft 13 of the powertrain 1 to the rear wheel. In the "hubdrive" type propulsion assembly 2,The upstream transmission 18 may be a chain 10 or a belt connecting the crankset 21 and the input body 11 of the drive unit 1, and the output body 13 may be the same as the rear wheel rim 16 (and therefore the downstream transmission 20 is absent). Alternatively, the upstream transmission 18 may be a chain or a belt (or any other type of transmission element) connecting the crankset 21 to the input body 11 of the drive unit 1, and the downstream transmission 20 may be a chain or a belt (or any other type of transmission element) connecting the output body 13 of the drive unit 1 to the rear wheel 16. This drive unit configuration could be used in certain specific bicycles, namely cargo bikes. 20 Figures 2 and 3 show different detailed functional views of Figure 1. The powertrain assembly 1 comprises a plurality of components,in particular rotating driven components. The drive unit 1 comprises a first motor 40 (M1) and a second motor 50 (M2). The drive unit 1 may include a current measuring element for the first motor 40 and a current measuring element for the second motor 50. The drive unit 1 further comprises a control unit 22. The control unit 22 is connected to the first motor 40 and the second motor 50 and is arranged to control the first and second motors. The angular position of the first and second motors can be determined by measuring elements 30. The measuring elements are, for example, magnets rotating on the motor shafts with respect to magnetic sensors, or more generally any Types of encoders: optical, magnetic, inductive, capacitive, etc. The control unit 22 controls the first motor 40 and the second motor 50 based on the angular position of the first motor 40, the angular position of the second motor 50, the current of the first motor 40 and the current of the second motor 50.5. This information having been provided to it by the measuring elements. The control unit 22 can control the first motor 40 in angular position or angular velocity. The control unit 22 can control the second motor 50 in current or torque, and as described below, during the resumption of pedaling, the control unit 22 can also control the second motor 50 in position, speed, or acceleration. Preferably, the drive assembly 2 includes one or more batteries 24 supplying electricity to any object or element requiring it in the drive assembly 2 or more specifically in the powertrain 1, such as the motors 40, 50, the control unit 22, sensors,etc.15 The first motor 40 can have the role of managing the speed ratio of the powertrain 1. One of its functions is to provide a given transmission ratio. This transmission ratio is the ratio between the angular velocity of the output body 13 of the powertrain 1 and the angular velocity of the input body 11 of the powertrain 1. This transmission ratio can 20, for example, be determined based on a speed ratio parameter provided by the cyclist or be determined by the control unit 22 in order to provide automatic gear changes to the cyclist. This determination can notably be carried out by a gear-shifting algorithm. The first motor 40 is preferably controlled in angular position or angular velocity,25 for example via the control unit 22 which controls the first motor in such a way that an angular position or angular velocity command is respected. The second motor 50 can be used to manage the correct level of assistance regulation for the powertrain. One of its functions is to assist the cyclist's movement by adding torque to that supplied by the cyclist and the first motor. In other words, the power supplied by the second motor is added to the power supplied by the cyclist and the first motor. Preferably, the level of assistance is determined by the control unit 22, based in particular on an assistance level parameter. The assistance level parameter can be determined by the cyclist or automatically by the powertrain control unit 22. The second motor is preferably controlled by current or torque, for example via the control unit 22. which controls the second motor in such a way that a current or torque setpoint is respected. Furthermore,The control unit 22 can control the second motor according to a torque setpoint with regulation. The powertrain combines electric assistance and a 10-speed automatic transmission. The powertrain provides a continuously variable transmission ratio. The control unit 22 can be configured to determine a rotational speed setpoint and to impose said rotational speed setpoint on the first motor 40.The rotation speed setpoint is determined as directly proportional to the rotation speed of the input body, obtained by calculation based on the angular position of the first motor and / or the second motor and the speed ratio parameter. The rotation speed of the input body can alternatively be measured directly on the input body (without being calculated based on the angular positions of the motors). The control unit can also be based on the speed ratio parameter and the powertrain assistance level parameter to control the second motor. The control unit 22 can be arranged to determine a current or torque setpoint and to impose said current or torque setpoint on the second motor 50. The current or torque setpoint of the second motor is 25 determined taking into account one or more criteria, in particular the torque or current of the first motor obtained by the current measuring element of the first motor, the speed of the first motor, the speed of the second motor,The powertrain speed ratio parameter and the powertrain assistance level parameter. Within the framework of inertia compensation 30 2025 / 5061 BE2025 / 5061 -13-, the setpoint of the second motor can be based on the acceleration or the speed of the input body 11. The powertrain 1 may also include a differential system 10(D). The use of a differential system 10 allows a continuous change in the speed ratio between the rotation of the output body 13 and the rotation provided by the cyclist to the input body 11. The differential system 10 may include a first input element 101 (with an angular velocity ω1), a second input element 102 (with an angular velocity ω2) and an output element 103 (with an angular velocity ω3). The input body 11 can be connected to the second input element 102 of the differential system 10. The input body 11 transmits the power supplied by the cyclist to the input of the differential system 10. The input body 11 can drive the second input element 102.preferably with a fixed ratio. The input body 11 can be indirectly connected to the second input element 102 via a first freewheel 26 (F1) between the pedal assembly 21 and the second input element 102 of the differential system 10. The input body 11 can be indirectly connected to the second input element 102 via the first freewheel 26. The function of the freewheel 26 is that the pedal assembly 21 can drive the input element 102 in the normal operating direction of the differential system, but that the second motor 50 cannot drive the pedal assembly 2120 in the normal operating direction (in the context of this document, the normal pedaling direction being the direction of rotation of the pedal assembly axis which corresponds to a forward movement of the pedal vehicle). Also, the freewheel26 is able to couple (synchronize) or decouple (desynchronize) the crankset21 and the second input element102. The input body11 can be 25 connected indirectly to the second input element102 via a reducer28 (RI1),modifying the angular velocity ωF1 of the first free wheel 26. Alternatively, the input body 11 can be directly connected to the second input element 102 – a connection establishing the link between the input body 11 and the second input element 102. 30 2025 / 5061 BE2025 / 5061 -14- The powertrain may include a second free wheel 30(F2) between the input body 11 and the output body 13 such that the input body 11 drives the output body 13 in the normal direction of operation. The input body 11 can be indirectly connected to the output body 13 via the second free wheel 30(F2). The input body 11 transmits the power supplied 5 by the cyclist to the output of the powertrain 1. This allows, for example, the cyclist to move the pedal-powered vehicle forward without the intervention of the motors 40, 50 – advantageous in case of failure of the latter or of one of the elements necessary for their power supply or control. The input body 11 can be indirectly connected to the output body 13 via a reducer 32 (RI2) and potentially a reducer 28 (RI1),modifying (i.e. multiplying or reducing) the angular velocity ωF2 of the second free wheel 30. The input body 11 can be connected indirectly to the output body 13 via a reducer 34 (R0), according to different paths. More specifically, the first free wheel 26 can be downstream of the input body 11 and can be connected to the second input element 102 directly or indirectly via the reducer 28. The second free wheel 30 can be downstream of the first free wheel 26, or downstream of the reducer 28 as appropriate, along different paths. The first free wheel 26 and the second free wheel 30 are arranged in such a way that the second input element 102 is able to drive the output body 13 via the first free wheel 26 and the second free wheel 30. In other words, the second free wheel 30 is in series with the first free wheel 26.between the input body 11 and the output body 13. The pedal assembly 21 (and the input body 11) can drive the second input element 102 via the first free wheel 26 in the normal direction of operation 25 and the pedal assembly 21 (and the input body 11) can possibly drive the output body 13 via the first free wheel 26 and the second free wheel 30 in the normal direction of operation. The figures schematically represent the different configurations and paths using the paths set, such that = ̅. If path α is active, then the second free wheel 30 is directly connected downstream of the first free wheel 26. If path β is active, then the second free wheel 30 is indirectly connected downstream of the first free wheel 26 via the reducer 28. The same applies with the paths set, such that = ̅. When the path is active, the input body 11 is indirectly connected to the output body 13 via the reducer 34. When the path is active,The input body 115 is directly connected to the output body 13 (without the intermediary of the reducer 34). The first motor 40 can be connected to the first input element 101 of the differential system 10. The first motor 40 can drive the first input element 101, preferably with a fixed ratio. The first motor 40 then manages the speed ratio of the powertrain 1. The first motor 40 can be indirectly connected to the first input element 101 via a reducer 24 (RM1). The reducer 24 modifies the angular velocity ωM1 of the first motor 40 to an angular velocity ω1. Alternatively, the first motor 40 can be directly connected to the first input element 101, without the reducer 24, the angular velocity ωM1 of the first motor 40 corresponding to the angular velocity ω1. The second motor 50 can be connected to the second input element 102 of the differential system 10 (according to Figure 2). The second motor 50 can drive the second input element 102,preferably with a fixed ratio. The second motor 50 allows the correct level of assistance regulation to be managed from the input 20 of the differential system 10. The second motor 50 can be connected indirectly to the second input element 102 via a reduction gear 36 (RM2). The reduction gear 36 modifies (i.e., multiplies or reduces) the angular velocity ωM2 of the second motor 50. The second motor 50 can also be connected to the output body 13 of the drive unit 25 1 (according to Figure 3). The second motor 50 can drive the output body 13,preferably with a fixed ratio. The second motor 50 allows the correct level of assistance regulation to be managed from the output of the differential system 10. The second motor 50 can be connected indirectly to the output body 13 via the reducer 36 (RM2). The reducer 36 modifies (i.e., multiplies or demultiplies) the angular velocity ωM2 of the second motor 50. 2025 / 5061 BE2025 / 5061 -16- The reducer allows the torque from the second motor to be multiplied. The second motor 50 can also be connected indirectly to the output body 13 via the reducer 34 (RO), according to different paths. As above, Figure 3 schematically illustrates the different configurations and paths using paths ε and ζ, such that ε = . When path ε is active, the second motor 50 is connected indirectly to the output body 13 via the reducer 34. When path ζ is active, the input body 11 is connected directly to the output body 13 (without the intermediary of the reducer 34). Furthermore,The second motor 50 is capable of driving the output body 13 in a direction corresponding to the normal direction of pedaling. According to Figure 2, the second motor 50 can drive the output body 13 via the second free wheel 30 (and optionally via the reduction gears 32, 34, 36). According to Figure 3, the second motor 50 can drive the output body 13 (and optionally via the reduction gears 34, 36). Thus, the second motor 50 is always capable of driving the output body 13 in a direction corresponding to the normal direction of pedaling. Thus, on the second input element of the differential system 10, the angular velocity ω2 can be an angular velocity coming from the pedal 21 (Figure 3) or be an angular velocity coming from the pedal 21 equal (because mechanically connected) to that coming from the second motor 50,

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