POWERTRAIN ASSEMBLY, VEHICLE, INSPECTION METHOD AND ASSEMBLY METHOD

Description

BE2024 / 5917 -2- ●An input body driven by a pedal assembly, the input body being connected to the second input element of the differential system, ●An output body driven in rotation by the output element of the differential system, and in which the output shaft of the first motor and the output shaft of the second motor extend through the plane comprising the face of the electronic board, the shaft driven by the first motor and the shaft driven by the second motor being on the same side of the plane. According to one variant, the group comprises a housing with several compartments, the first motor, the second motor and the electronic board are in the same first compartment and the shafts are in a second compartment. According to one variant, the group also includes a structural part delimiting the first and second compartments of the casing. According to another variant, the electronic board extends parallel to and against the structural part, the structural part supporting at least one of the parts among a bearing of the output shaft of the first motor.The output shaft bearing of the second motor is located on the electronic board. In one variant, the housing comprises a first shell defining the first compartment with the structural part and a second shell defining the second compartment with the structural part, the first and second shells being on either side of the structural part. In another variant, the assembly further comprises a first seal between the first shell and the structural part and a second seal between the second shell and the structural part. In another variant, the first and second motors have supply windings positioned with respect to the first shell opposite the electronic board. In another variant, the first and second motors have identical output shaft lengths between the electronic board and the first shell. 2024 / 5917 BE2024 / 5917 -3- According to a variant,The group also includes a second free wheel between the input and output bodies such that the input body drives the output body at least at the same speed in the normal direction of pedaling. In one variant, the group also includes a first free wheel between the crankset and the input element of the differential system. In another variant, the second free wheel is arranged such that the second input element is capable of driving the output body via the second free wheel. In yet another variant, the group also includes a third free wheel between the output element of the differential system and a rear wheel of the 10-pedal vehicle, the free wheel being capable of coupling or uncoupling the rear wheel and the crankset. According to one variant, the electronic board is the sole electronic control board for the first and second motors and supports the current control bridge of the first motor and the current control bridge of the second motor, execution components of the control algorithm for the 15 motors,and the measurement of the angular positions of the output shaft of the first motor and the output shaft of the second motor. According to one variant, the group includes several sensors on the electronic board, the sensors being capable of measuring the angular positions of the output shaft of the first motor and the output shaft of the second motor.20 According to one variant, the group further includes a crank axle through the plane comprising the face of the electronic board and a sensor on the electronic board, the sensor being capable of measuring the angular position of the crank axle. According to one variant, at least one of the sensors is of the inductive type.25 According to one variant, the differential system comprises a planetary gear forming the first input element and a ring gear forming the second input element and one or more transmission components between, on the one hand, the pinion shaft of the second motor and, on the other hand, the ring gear, the transmission components comprising at least one or more intermediate gears.30 2024 / 5917 BE2024 / 5917 -4- According to one variant,The differential system further comprises a satellite carrier forming the output element, the satellite carrier being connected to the output body by a gear, the satellite carrier being in the ring gear, the satellite carrier and the gear being connected through the ring gear by a spline. According to one variant, the group further comprises power supply and information exchange connectors for the powertrain group, the connectors being located on the electronic board and accessible through the casing. According to one variant, the group is capable of driving a rear wheel of the pedal vehicle by a downstream transmission, the downstream transmission being of a flexible type such as a chain or a belt. According to one variant, the pedal assembly is connected to the second input element. According to one variant, the group also includes a direct connection between the electronic board and the power windings of the first and second motors. 15 According to another variant,The first and second motors comprise stators which are juxtaposed in the crankcase and aligned along a direction of an axis of the pedal assembly. The invention also relates to a pedal vehicle, comprising a propulsion assembly including the motor-propulsion group as described above. The invention also relates to a method for controlling a powertrain of a pedal-powered vehicle propulsion system as described above, the pedals being driven by a cyclist. The method comprises: ● a first operating mode in which the cyclist provides torque to the pedals, the control unit determines a rotational speed command for the first motor and drives this motor according to this command, the rotational speed control acting on the speed ratio between the output and input bodies, and ● the control unit determines a torque or current command for the second motor and drives this motor according to this command, this command corresponding to a level of total assistance,● A second operating mode in which the cyclist applies torque to the crankset, the control unit determines only a driving command in torque or current, corresponding to an assistance level, for the first and / or second motor and drives this or these motors according to this command, and the speed ratio between the output body and the input body is mechanically fixed. According to a variant, the method further includes a third operating mode in which the cyclist provides torque to the crankset, and the control unit does not determine a driving command for the first or second motor. According to a variant, in the third operating mode, the torque provided by the first and second motors is zero. According to one variant, in the second operating mode, ●The control unit determines a torque control command corresponding to an assistance level for the first motor and for the second motor, ●The torque supplied by the cyclist at the pedals is positive, ●The torque supplied by the second motor is positive,●The torque supplied by the first motor is negative, ●The speed of the first motor is negative. 25 According to one variant, the method further includes controlling the second operating mode by estimating the mass of the vehicle and the cyclist. According to another variant, the estimation of the mass of the vehicle and the cyclist is done during the first operating mode. 2024 / 5917 BE2024 / 5917 -6- According to one variant, the method further includes controlling the second operating mode by distributing the torque supplied by the first motor, by the second motor or by the torques of the two motors. According to one variant, the process further comprises a step of switching from one operating mode to another, the switching from one operating mode to another being achieved by continuously adapting the torque and speed between the operating point of one operating mode and the other. According to one variant, the adaptation of the operating point in terms of speed and torque is done sequentially, starting with the speed or the torque, or is done simultaneously. According to one variant,The torque of the cyclist on the crankset is estimated, on the one hand, by measuring the deformation of a section of the kinematic chain of the powertrain traversed by the cyclist's effort, by comparing the position at the two ends of this section, and, on the other hand, by the stiffness of this section determined beforehand.15 According to a variant, the process is such that ●In the first mode of operation, the input body is coupled to the second input element by the first free wheel and the input body is decoupled from the output body by the second free wheel, ●In the second mode of operation, the input body is coupled20 to the second input element by the first free wheel and the input body is coupled to the output body by the first free wheel and by the second free wheel. According to one variant, when the cyclist does not apply torque to the crankset, canceling torques are applied by the first and second motors to constrain the transmission. 25 The invention also relates to a method of assembling the powertrain as described above,including ●The supply of the first motor, the second motor, the electronic board, a first shell and a structural part, ●The assembly of the electronic board to the structural part, 30 2024 / 5917 BE2024 / 5917 -7- ●The assembly of the first motor and the second motor in the first shell, ●The closing of a first compartment by the structural part by assembling the structural part with the first shell, the structural part being assembled with the first shell with the electronic board in the first compartment, The first compartment being supplied in the form of a partially closed module. According to one variant, the process further comprises: ● The supply of transmission gears and a second shell, 10 ● The assembly of the transmission gears to the module formed by the first compartment, ● The closure of a second compartment by assembling the second shell to the structural part, the second compartment enclosing the transmission gears. 15 According to one variant, the powertrain comprises: ● A target mounted to rotate on a crankshaft,lacible having a circumferential irregularity ●at least one inductive type sensor on the electronic board, the sensor being capable of detecting the rotations of lacible, 20 the process comprising, before the closure of the second compartment, ●fixing lacible to the crank axle, ●assembling the crank axle and lacible to the module formed by the first compartment, the circumferential irregularity of lacible being oriented to ensure the passage of lacible relative to the transmission gears 25 assembled to the module formed by the first compartment. The use, in this document, of the verb "comprendre" (to understand), its variants, and its conjugations, cannot in any way exclude the presence of elements other than those mentioned. The use, in this document, of the indefinite article "un" (a / an), "une" (an / an), or the definite article "le" (the), "la" (the), or "l'" (an / an) to introduce an element does not exclude the presence of a plurality of these elements. 2024 / 5917 BE2024 / 5917 -8- The terms "premier" (first), "deuxième" (second), "troisième" (third), etc., are, for their part, used in this document exclusively to differentiate different elements.without implying any order between these elements. The set of preferred embodiments, as well as all the advantages of the powertrain according to the invention, are transposed mutatis mutandis to the present vehicle, control method, and assembly method, and vice versa. The different embodiments can be considered alone or in combination. Brief description of the figures. Other features and advantages of the present invention will become apparent upon reading the detailed description that follows, for the understanding of which reference should be made to the accompanying figures, which show: - Figure 1, an example of a functional view of a powertrain in which the powertrain is implemented; - Figure 2, a detailed functional view of Figure 1; - Figure 3, a schematic view of a powertrain of Figure 2; The drawings of the figures are not to scale. Similar features are generally denoted by similar reference numerals in the figures. Within the context of this document, identical or analogous features may carry the same reference numerals. Furthermore,The presence of reference numbers or letters 20 in the drawings cannot be considered limiting, including when such numbers or letters are indicated in the claims. Detailed description of embodiments of the invention The invention relates to a powertrain of a pedal vehicle propulsion system, the powertrain comprising a differential system, a first electric motor and a second electric motor, an electronic board supporting at least one control unit capable of controlling the first and second motors. The first and second motors each have an output shaft driven by a rotor, each output shaft driving a shafted pinion. The powertrain is such that the output shaft of the first motor and the output shaft of the second motor extend through a plane comprising a face of the electronic board,The pinion shaft driven by the first motor and the pinion shaft driven by the second motor are on the same side of the plane. This allows for a simpler assembly of the powertrain. Figure 1 is an example of a functional view of a powertrain assembly 2 in which a powertrain assembly 1 can be implemented. The powertrain assembly 2 is contained within a pedal vehicle. The powertrain assembly 2 is schematically represented between a cyclist 5(C) and a rear wheel 16 (with an angular velocity ωW). The pedal vehicle can, for example, be a bicycle, a tricycle, or 10 others. In particular, it is a bicycle,The drive unit 2 includes a crankset 21 (including pedals) operated by the cyclist 5. The crankset allows the cyclist to propel the vehicle with or without the assistance regulation of electric motors described later. The drive unit 2 includes the powertrain 1 (PU) which may 15 be located at the level of the crankset 21 (a "mid-drive" type drive unit 2). The powertrain 1 may include an input body 11 and an output body 13. The crankset 21 may be identical with the input body 11 of the powertrain 1. Alternatively, the output body 13 may be identical with the wheel rim 16. The drive assembly 2 may include an upstream transmission 18 (Tin) between the crankset 21 and the input body 11 of the drive unit 1. The upstream transmission 18 connects the crankset 21 and the input body 11 together. The upstream transmission 18 may be of a flexible type, for example a chain, a belt, 25The upstream transmission 18 can modify the angular velocity ωCK of the crankshaft (or crankshaft axle) into an angular velocity ωI. The upstream transmission 18 may be optional. The drive assembly 2 may include a downstream transmission 20 (All) between the output body 13 of the drive unit 1 and one or more rear wheels 30 16 of the vehicle. The downstream transmission 20 connects the output body 13 and one or more rear wheels 16. The downstream transmission 20 can modify the angular velocity ωO of the output body 13 into an angular velocity ωTO. The downstream transmission 20 may be optional. The downstream transmission is, for example, of a flexible type such as a chain or a belt. Thus, in the "middrive" type propulsion assembly 2 of a vehicle with 5 the powertrain 1 located at the pedal assembly 21, the pedal assembly 21 can be confused with the input body 11 (and therefore the upstream transmission 18 is absent) and the downstream transmission 20 can be a chain or a belt connecting the output body 13 of the powertrain 1 to the rear wheel. Alternatively,the upstream transmission 18 may be a first chain or a belt (or any other type of transmission element) connecting the crankset 21 to the input body 11 of the powertrain 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 powertrain 1 to the rear wheel 16. This alternative powertrain configuration could be used in certain specific bicycles 15, called cargo bikes. Figure 2 shows a detailed functional view of Figure 1. The powertrain 1 comprises a first motor 40 (M1) and a second motor 50 (M2). The powertrain 1 may further comprise a differential system 10 (D). The use of a differential system 10 allows a continuous change 20 of the transmission ratio (or speed ratio) between the rotation of the output body 13 and the rotation supplied by the cyclist to the input body 11. The differential system 10 may comprise 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). 25 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 drive unit can include a first free wheel 26 (F1) between the crankset 30 and the second input element 102 of the differential system 10. The input body 11 can be connected indirectly to the second input element 102 by the intermediary of the first free wheel 26. The function of the free wheel 26 is that the pedal assembly 21 can drive the second input element 102 in the normal operating direction of the differential system, but that the second motor 50 cannot drive the pedal assembly 21 in the normal operating direction (in the context of this document,The normal direction of pedaling is the direction of rotation of the crank axle which corresponds to a forward movement of the pedal vehicle. The input body 11 can be connected indirectly to the second input element 102 via a reducer 28 (RI1), modifying the angular velocity ωF1. Alternatively, the input body 11 can be connected directly to the second input element 102 – a connection establishing the link between the input body 11 and the second input element 102. The powertrain may include a second free wheel 30 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 may be indirectly connected to the output body 13 via the second free wheel 30 (F2). The input body 11 can then transmit the power supplied by the cyclist to the output of the powertrain 1. The input body 11 may be indirectly connected to the output body 13 via a reduction gear 32 (RI2) and potentially the reduction gear 28 (RI1).modifying (that is to say multiplying or demultiplying) the angular velocity ωF2. 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 25 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, according to 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 30 26 and the second free wheel 30. In other words, the second free wheel 30 2024 / 5917 BE2024 / 5917 -12- 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, 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. Figure 2 schematically represents the different configurations and paths using the paths set, such that = ̅. If path α is active (the second free wheel 30 is directly connected downstream of the first free wheel 26), then: 10 = 1 → = ↓ = 0 → = 1 (x denoting any variable). If path β is active (the second free wheel 30 is indirectly connected downstream of the first free wheel 26 via the reducer 28), then: =1 →= ↓=0 →=1 15 The same applies to paths β, 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 body11 is directly connected to the output body13 (without the intermediary of the reducer34). The first motor 40 can be connected to the first input element 101 of the differential system 20. 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 connected indirectly to the first input element 101 via a reduction gear 24 (RM1). The reduction gear 24 modifies the angular velocity ωM1 of the first motor 40 to an angular velocity ω1. Alternatively, the first motor 40 can be connected directly to the first input element 101, without the reduction gear 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. 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 of the differential system 10. The second motor 50 can be connected indirectly to the second input element 102 via an intermediate reduction gear 36 (RM2). The reduction gear 36 modifies (i.e., multiplies or demultiplies) the angular velocity ωM2 of the second motor 50 to an angular velocity ω2.10 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). Thus, the second The motor 50 is always capable of driving the output body 13 in a direction 15 corresponding to the normal direction of pedaling. The drive assembly 2 may also include a third free wheel 14 (F3). The third free wheel 14 is located between the pedal assembly 21 and a rear wheel 16 of the pedal vehicle.The freewheel is capable of coupling (synchronizing) or decoupling (desynchronizing) the rear wheel and the crankset. The freewheel allows the interruption of pedaling (and the interruption of the rotation of the crankset axle) while allowing the vehicle to continue its movement in the direction of travel. The freewheel is, for example, located between the output element 103 of the differential system and the rear wheel 16. The freewheel 14 is located, for example, downstream of the output body 13. The freewheel 14 is located, for example, downstream of the transmission 20, if applicable. The third freewheel 14 is located, for example, in the hub of the rear wheel. The differential system 10 can be, for example, an epicyclic gear train (as described below in connection with Figure 3). The epicyclic gear train comprises a planet gear, a ring gear, and a planet carrier and one or more planets 30 (single or double), carried by the planet carrier,between the planetary gear and the ring gear. 2024 / 5917 BE2024 / 5917 -14- The first input element 101 can be the planetary gear. The second input element 102 can be the ring gear and the output element 103 can be the planet carrier. Alternatively, the second input element 102 can be the planet carrier and the output element 103 can be the ring gear. The equations of the powertrain elements are as follows.5 In all that follows, "R" denotes the ratio of the part designated subsequently (according to the convention above). For example, "RDU" means the ratio of the powertrain 1 (DU), or "RRM1" means the ratio of the reduction gear 24 (RM1). The transmission ratio of the powertrain is: =10. A characteristic of powertrain 1 is its ratio range. Ratio range = The consecutive equation of the differential system 10 is: =1−3 2−3. The following equations are written in relation to Figure 2. The 15 consecutive equations of the internal transmissions (reducers 24, 36, 34, 28,32) The consecutive equations of the upstream transmissions 18 and downstream transmissions 20 are respectively: =25 2024 / 5917 BE2024 / 5917 -15- = The consecutive equations of the freewheels 26, 30, 14 are: 1≥↔1=≥1 2≥11↔2=≥1 ≥↔3=≥15 In this context, but also independently of this context, Figure 3 shows a schematic view of the powertrain 1 according to a preferred embodiment. Figure 3 shows a schematic view of the powertrain 1 in Figure 2. In the mode of Figure 3, the paths and are shown. The 10 reduction gears 24 (RM1), 32 (RI2) as well as the upstream transmission 18 (Tin) are not present. 36 is formed by a shafted pinion 54, a toothing 37 of the ring gear 102 and an intermediate gear wheel 35. The reduction gear 28 is formed by a gear wheel 29 and a gear wheel 27 of the ring gear 102. The powertrain 1 includes the first motor 40 and the second motor 50. In this example,The differential system 10 is an epicyclic gear train comprising transmission components. The epicyclic gear train comprises a planetary gear which is a shaft pinion corresponding to the first input element 101, a ring gear corresponding to the second input element 102, a planet carrier corresponding to the output element 103, and 20 one or more planets 52 (single or double),carried by the satellite carrier 103. The satellites 52 are between the planetary 101 and the crown 102 (and are interlocked). The satellites 52 are guided in rotation relative to the satellite carrier 103 by a bearing 69. The satellite carrier 103 is connected by a spline 78 to the output plate corresponding to the output body 13. The output plate 13 is driven in rotation 25 by the satellite carrier 103 via the reducer 34 (formed by the gears 33 and 38) and the spline 78. The output plate 13 is guided in rotation relative to a housing 56 (described later) by a bearing 70. The 2024 / 5917 BE2024 / 5917 -16- crankset 21 (axle 211 of the crankset) is guided in rotation relative to the output plate 13 and relative to the housing 56 by bearings 66. The first motor 40 includes an output shaft 402 driven by a rotor 404. The output shaft 402 drives a pinion shaft which is the planetary gear and the first input element 101. The pinion shaft 101 (or pinion shaft) can be, for example, a pinion machined directly onto the output shaft 402 or,for example pressed on the output shaft 402. The shaft pinion 101 and the output shaft 402 can be one piece, can be of one piece. The first motor 40 includes in addition a stator 406, driving the rotor 404. The second motor 50 also includes an output shaft 502 driven by a rotor 504. The output shaft 502 drives a pinion shaft 54. The pinion shaft 54 ​​(or pinion shaft) can be, for example, a pinion machined directly onto the output shaft 502 or, for example, pressed onto the output shaft 502. The pinion shaft 54 ​​and the output shaft 502 can be a single unit. The second motor 50 also includes a stator 506, driving the rotor 504. The second motor 50 is connected to the differential system 10 by the pinion shaft 54. The pinion shaft 54 ​​is connected to the teeth 37 of the ring gear 102 by one or more transmission components such as the intermediate gear wheel 35. The shafted pinion 54,The gear teeth 37 of the crown gear 102 and the intermediate gear 35 form the reduction gear 36. The intermediate gear 20 35 allows the motion to be transmitted between the shaft pinion 54 and the gear teeth 37 without changing the reduction ratio. The gear 35 ensures the connection between the shaft pinion 54 and the gear teeth 37 even though the distance between the shaft pinion 54 and the gear teeth 37 is fixed by the diameters of the first and second motors. If a direct transmission were to be ensured between the shaft pinion 54 and the gear teeth 25 37 with a chosen reduction ratio, this would lead to shaft pinion 54 and gear teeth 37 diameters that would be large and bulky. The gear 35 avoids this. The powertrain 1 includes an electronic board 19 supporting a control unit 22 (not visible in Figure 3). The electronic board 19 supports all or part of the electronic components forming the control unit 22. The control unit 22 is capable of controlling the first engine 2024 / 5917 BE2024 / 5917 -17- 40 and the second engine 50. The control unit 22 is connected to the first engine 40,The second motor 50 is arranged to control the first and second motors. The electronic board 19 has one face contained within a plane 80. The electronic board is a printed circuit board (PCB), which is a flat substrate on which various electronic components are mounted and connected – particularly for motor control. The flat substrate comprises a first face and a second face, one of these faces being contained within the plane 80. The electronic board has a shape adapted to the configuration of the powertrain. The output shaft 402 of the first motor 40 and the output shaft 502 of the second motor 50 extend through the plane 8010, which includes the face of the electronic board 19 (not only the abstract axis of rotation of the shafts, but the physical shafts are also through the board). electronic19). The output trees 402 and 502 can pass through an opening in the card, the opening being circumscribed by the card itself. The opening can also be a notch in the card,the opening not being circumscribed by the card itself (the opening opening into the plane 80). The shaft pinion 101 driven by the first motor 40 and the shaft pinion 54 driven by the second motor 50 are on the same side of the plane 80. In other words, the first motor 40 (comprising its rotor 404 and its stator 406) and the second motor 50 (comprising its rotor 504 and its stator 506) are on the same side of the plane (and with regard to one face of the electronic board 19) and the shaft pinions 101, 54 are on the other side of the plane (and with regard to the other face of the electronic board 19, which could be the one in the plane 80). The first and second motors 40, 50 are (essentially) aligned on the side of their mechanical output (shaft pinions), so as to interface with the electronic board 19 (which is 25 perpendicular to the axes of rotation of the shafts). This facilitates the assembly of the powertrain. 1. Also,This facilitates the placement of the electronic board and the connection between the electronic board and the parts powered and / or controlled by the electronic board (such as the connection of the motors to the board). The intermediate position of the board in the powertrain assembly also facilitates the placement of the electronic components of the board. Furthermore, this allows the first and second motors to be arranged with parallel axes of rotation of the output shafts, arranged so that the center distance is reduced to a maximum, making the powertrain more compact. In Figure 3,The powertrain also includes the pedal assembly 21 which corresponds to the input body 11. The pedal assembly 21 (forming the input body 11) is connected to the crown 102 (forming the second input body). The powertrain 1 includes a casing 56. The casing 56 supports the guide bearings of the transmission components. The casing 56 protects the powertrain 1 from the environment. The casing 56 protects the parts of the powertrain 1 (such as electronic components and transmission components) from weather and dirt. It also protects the rider. The casing 56 encompasses all the parts (such as electronic components and transmission components) of the powertrain 1, except for the crankset 21 and the chainring 13. The crankset 21 passes through the casing 56 (which supports the crankset bearings 66), and the chainring 13 is located outside the casing 56. The casing 56 may include several compartments. The first motor 40, the second motor 50 and the electronic board 19 can be in the same first compartment 561 and the shafted gears 101,54 are in the same second compartment 562. This 20 allows the motors to be isolated from the transmission components. This allows the clean (grease-free) part of the powertrain, containing the motors and the electronic board 19, to be separated. This also allows the motors and the electronic board 19 to be assembled in one of the compartments and then the other components to be assembled in the other compartment – ​​for example, at different times and locations 25 than the powertrain assembly. This facilitates the construction of the powertrain. The powertrain thus combines electric assistance and an automatic transmission in the same housing. According to Figure 3, the powertrain assembly 1 also includes a structural part 58 delimiting the first compartment 561 and the second compartment 562 of the casing 56. The structural part 58 facilitates the joining of the compartments to each other. The structural part 58 also facilitates the positioning of the various parts within the powertrain assembly 1. For example, the output shafts 402,502 of the first and second motors 40, 50 are guided in rotation relative to the structural part 58 respectively by bearings 60, 62. The bearings 60, 62 are supported by the structural part 58 between on one side the rotors and stators of the motors and on the other side the shafted pinions 101, 54. Also, the gear 35 and the planet carrier 103 are also guided in rotation relative to the structural part 58 respectively by a bearing 64 and a bearing 65. The gear 35 can be held only by the structural part 58 or by the structural part 58 and the housing 5610 (as seen in figure 3). The structural part 58 also allows the assembly of the casing 56 comprising a first shell 71 and a second shell 72. The first shell 71 defines the first compartment 561 with the structural part 58. The second shell 72 defines the second compartment 562 with the structural part 58. The first shell 71 and the second shell 72 are on either side of the structural part 58. In Figure 3,Fasteners 74 allow the first shell 71 and the second shell 72 to be fixed to the structural part 58. A first seal between the first shell 71 and the structural part 58 and a second seal between the second shell 72 and the structural part 58 can be provided. The 20 seals can be held in position at the interface between the first and second shells 71, 72 and the structural part 58 to ensure the sealing of compartments 561, 562. The fasteners 74 can hold the seals in place. The seals can be a joint following the circumference of the shells 71, 72. The structural part 58 extends beyond the space defined by the housing 56, delimiting the two compartments and facilitating the construction of the powertrain assembly 1. The structural part 58 is an essentially flat part. This part can be described as a spacer such that the interface between the spacer and each of the shells 71, 72 forms a closed ring. The structural part 5830 is a rigid part that connects the two shells 71, 72 and holds them together. Furthermore,The electronic board 19 can be positioned parallel to and against the structural part 58. As both are flat parts, the electronic board 19 can be supported against the structural part 58 in position within the first compartment 561. The structural part can be positioned with respect to the face of the electronic board 19 contained within the plane 80. The advantage of such a structural part 58 is that the electronic board 19 can thus be easily positioned within the housing 56 while providing a large surface area to accommodate numerous electronic components. The structural part 58 allows for the manipulation of a mechanical part rather than the electronic board 19 during assembly, avoiding the risk of improper handling that could 10 damage the electronics. The structural part 58 allows for stable and transportable partial assemblies of the powertrain 1. These partial assemblies can be the electronic board 19 on the structural part 58, the engines 40, 50 in the first compartment 561 delimited by the first hull 71 or even,These two assemblies form a partially closed module. The position of the electronic board 19 between the motors 40, 50 and the shaft-mounted pinions 101, 54 allows the electronic board 19 to be positioned in a more central area of ​​the housing 56 and thus further away from the hulls 71, 72. In particular, the first motor 40 and the second motor 50 have power windings 20 positioned with respect to the first hull 71, opposite the electronic board 19. Since the electronic board 19 is in an equatorial area of ​​the housing 56 (and not against the housing), the motor windings can be at the bottom of the housing. This allows for better thermal management and better cooling of the motors. The electronic board 19 is cooled by the heat flow in the structural part 25. The powertrain also includes a direct connection between the electronic board 19 and the power supply windings of the first motor 40 and the second motor 50. Due to the position of the electronic board 19 relative to the motors, the motors 40 and 50 are positioned close to the electronic board 19. The motors 40,50 are in view of the electronic board 19. The 30 electrical connection between the motors and the board is not hindered by 2024 / 5917 BE2024 / 5917 -21- powertrain components. The electrical supply connection between the motors 40, 50 and the electronic board 19 is facilitated. The first motor 40 and the second motor can have identical output shaft lengths 402, 502 between the electronic board 19 and the first shell 71. This maximizes the power and torque capacity of the motors 40, 50 while maintaining the lateral space between the pedals under constraint (Q-factor). This also helps to facilitate the manufacture of the housing 56 and the assembly of the powertrain 1. The motors 40, 50 can have shafts 402, 502 passing through their respective rotors and stators. The shafts 402, 502 can extend from the bottom of the first shell 71, through the plane 8010 comprising the face of the electronic board 19, and up to the second compartment. 562. The output shafts 402, 502 can be guided in rotation relative to the first shell 71 respectively by bearings 61,63. Preferably, the electronic board 19 is the single electronic control board for the first motor 40 and the second motor 50. The electronic board 19 supports the current control chopper bridge of the first motor 40 and the current control chopper bridge of the second motor 50. The electronic board 19 supports the side components for executing the motor control algorithm such as a microcontroller or equivalent systems such as a programmable chip, FPGA (for "Field-programmable gate array",corresponding to 20 a "field-programmable gate network"). The electronic board 19 can also support the measurement of the positions of the output shaft 402 of the first motor 40 and the output shaft 502 of the second motor 50. The electronic board 19 can also support the electronic components responsible for executing a high-level control algorithm of the powertrain 1 (in particular for 25 the calculation of the torque of the second motor 50 to ensure the level of assistance of the second motor 50 and the speed). The presence of a single electronic control board 19 reduces manufacturing costs because it limits the use of expensive connectors. The control unit 22 controls the first motor 40 and the second motor 5030 based on the angular positions of the first motor 40, the angular positions of the second motor 50, the angular velocity of the first motor 40, the angular velocity of the second motor 50, the current of the first motor 40 and / or the current of the second motor 50, this information having been provided to it by the measuring elements. To this end,The powertrain 1 may include several sensors 76 on the electronic board 19, the sensors 76 being capable of measuring the angular positions of the output shaft 402 of the first motor 40 and the output shaft 502 of the second motor 50. An additional sensor 76 may be provided to measure the angular position of the pedal assembly 21. More specifically, the powertrain 1 includes the pedal assembly shaft 211 through the plane 80 comprising the face of the electronic board 16 and the sensor 76 measures the angular position 10 of the pedal assembly shaft 211. Thus, by way of example, three sensors 76 are present. For example, the sensors 76 detect the rotational movements of a target 77 mounted for rotation on the shafts 402, 502 and the axle 211 of the crankset. The targets 77 have alternating (phase-dependent) electrically conductive and non-conductive parts 15. Generally, the alternations occur regularly around the entire circumference. In some embodiments, the targets have protrusions, for example, in the shape of flower petals,That is to say, the non-conductive parts are not materialized. The targets 77 include a conductive material 20 (electrically) for the conductive and materialized parts. The targets 77 rotate with respect to the coils of the sensors 76, printed on the electronic board 19. The transmitting coil of the sensors 76 is electrically powered, which generates a magnetic field in which the target 77 rotates. The rotation of the target 77 then in turn generates an induced current in 25 the receiving coil(s) (a minimum coil) of the sensor 76. This makes it possible to detect the rotations of the shafts 402, 502 and axle 211, and therefore to know the angular position of the motors 40, 50 and pedal assembly 21. The positioning of the satellite carrier 103 in the casing 56, and particularly in the second compartment 562, is carried out in a compact manner,so as to reduce the overall size. The satellite carrier 103 is housed in the ring 102. The 2024 / 5917 BE2024 / 5917 -23- satellite carrier 103 is guided in rotation relative to the structural part 58 by the bearing 65 and relative to the ring 102 by the bearing 59. The satellite carrier 103 allows the satellites 52 to be positioned with respect to an internal toothing 31 of the ring 102. The satellite carrier 103 is also connected in rotation with the gear 38, through the ring 102. The ring 102 can be solid 5 and the satellite carrier 103 and the gear 38 can be connected through The crown 102. To facilitate assembly, the planet carrier 103 and the sprocket 38 are connected through the crown 102 by the spline 78. The sprocket 38 is guided in rotation relative to the housing 72 by a bearing 67 and relative to the crown 102 by a bearing 68. Figure 3 shows the freewheels 26 and 30. The first freewheel 26 is implemented between the crankset 21 (the bottom bracket axle 211) and the sprocket 29. The wheel 29 is meshed with the sprocket 27 of the crown 102,which is the second input element of the differential system 10. The second free wheel 30 is arranged in such a way that the ring 102 forming the second input element is 15 able to drive the plate 13 forming the output body via the second free wheel 30. The powertrain 1 also includes power supply and information exchange connectors 90 for the powertrain 1. The connectors 90 are on the electronic board 19 and are accessible through the housing 20 56. The connectors 90 (external) are directly implemented on the electronic board 19. A seal (visible in Figure 3) is provided between the connectors 90 and the housing 56. This facilitates the construction of the powertrain and ensures the housing is sealed. The powertrain assembly 1 includes an arrangement of its constituent parts 25 allowing for space optimization to make the assembly less bulky and easier to assemble. The motors 40 and 50 are of identical (or substantially identical) length along the direction of the axis 211 of the pedal assembly 21. More specifically,The stators 406 and 506 have the same (or nearly the same) length along this direction. In other words, the length 30 occupied by the stators between the housing 71 of the casing 56 and the electronic board 19 2024 / 5917 BE2024 / 5917 -24- is the same (or nearly the same) along this direction. The motors 40 and 50, in particular the stators 406 and 506, are juxtaposed in the casing 56 (the housing 71) aligned along the direction of the axis 211 of the crankset 21. In addition, the center distance between the output shafts 402 and 502 is at a minimum. Furthermore, the structural part 58 is in a medium plane 82. The transmission components such as the wheels 5 toothed wheels forming the differential system, the gears between the input body and the second input element, as well as the gears between the output element of the differential system and the output body extend along respective mean planes 83, 84, 85, etc. Along a direction along the axis 211 of the pedal assembly, the powertrain 1 comprises successively the first and second motors 40, 50 juxtaposed, the plane 80 comprising the face of the electronic board 19,the average plane 82 then the respective average planes of the transmission members 83, 84, 85, etc. The planes are parallel to each other and perpendicular to the axis 211 of the crankset. During vehicle operation, the cyclist can propel the vehicle forward by pedaling in the normal pedaling direction. The cyclist can provide torque. The cyclist can be assisted by the first and second motors, which can add or subtract torque from that provided by the cyclist. The cyclist can stop pedaling while the vehicle continues its movement, freewheeling. The invention also relates to a method for controlling the powertrain of a pedal-powered vehicle. The method may include a first operating mode (corresponding to a first operating mode in which the powertrain is configured). In the first operating mode,The cyclist provides torque to the crankset 21 and 25. The control unit 22 determines a speed control command for the first motor 40 and controls this motor according to this command. This allows the speed ratio between the output body 13 and the input body 11 to be controlled. The control unit 22 determines a torque or current control command (corresponding to a total assistance level) for the second motor 50 and controls this motor according to this command. In the first operating mode, according to the kinematics of the differential system 10, the first motor 40 is speed-controlled to act on the speed ratio between the output body 13 and the input body 11, and the second motor 50 is torque-controlled to act on the assistance level. In other words, in the first mode of operation,The control unit 22 determines a speed control command for the first motor 40 to act 5 on the speed ratio between the output body 13 and the input body 11, and the control unit 22 determines a torque control command for the second motor 50 corresponding to a level of total assistance. Thus,The powertrain combines electric assistance and an automatic transmission. The powertrain provides a continuously variable transmission ratio (or 10 speed ratios). According to the first operating mode of the process, the first motor 40 has 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 15 and the angular velocity of the input body 11 of the powertrain 1. This transmission ratio can, for example, be determined based on a speed ratio parameter provided by the cyclist or be determined automatically by the control unit 22 in order to provide the cyclist with a continuous or discrete speed change. This determination can, in particular, be carried out 20 by a speed-shifting algorithm. The first motor 40 can be controlled in angular position or angular velocity,for example via control unit 22 which controls the first motor in such a way that an angular position or angular velocity setpoint is respected. According to the first operating mode of the process, the second motor 5025 is responsible for managing the correct level of assistance regulation of 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. 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 can be controlled by current or torque, for example via the control unit 22 which controls the second motor in such a way that a setpoint of current or torque must be respected. Furthermore,The control unit 22 can control the second motor according to a torque setpoint with regulation. The control unit 22 can be arranged to determine a rotational speed setpoint and to impose said rotational speed setpoint on the first motor 40, the rotational speed setpoint being determined as a function of the speed of the second motor 50 and / or the pedal speed. The control unit 22 can also be based on the speed ratio parameter and the powertrain assistance level parameter to control the second motor 50. 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 15 is determined taking into account one or more criteria, including 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. 20 More specifically, in the first operating mode, the first motor 40 transmits its motion to the first input element 101 of the differential system 10 (the pinion shaft 101 in Figure 3), possibly via the reduction gear 24 (not shown in Figure 3). The action of the first motor 40 is transmitted to the pinion shaft forming the first input element 101 of the differential system 25 10. The cyclist 5 provides torque on the crankset 21, the motion then being transmitted to the input body 11, possibly via the upstream transmission 18. The input body 11 can also be confused with the crankset 21, as is the case in Figure 3. In the case of pedaling in the normal direction, the motion is transmitted from the input body 11 to the ring forming the second input element 30 102 of the differential system 10, possibly via the reducer 28 2024 / 5917 BE2024 / 5917 -27- (comprising the gear 29 and the gear 27). The cyclist is assisted in his movement by the second motor 50 which can act,jointly with the cyclist, on the ring forming the second input element 102 of the differential system 10. The movements performed on the input elements 101 and 102 of the differential system 10 are combined into a movement transmitted to the planet carrier forming the output element 103 of the differential system 10. This movement is then transmitted to the plate forming the output body 13, possibly via the reducer 34 (comprising the gears 33 and 38). The output body 13 transmits its movement to the wheel 16, possibly through a downstream transmission 20, and possibly through the third free wheel 14. The output body 13 can be confused with the wheel 16. In the first operating mode, the input body 11 is coupled to the second input element 102 (the ring in Figure 3) by the first freewheel 26 (conducting) and the input body 11 is decoupled from the output body 13 by the second freewheel 30 (non-conducting). The second freewheel 30 is non-conducting.so that no torque is transmitted from the input body 11 to the output body 13 without passing through the differential system 10. Combining the consecutive equations of the internal transmissions (of the reducers 24, 36, 34, 28, 32) with the consecutive equation of the differential system 10:20 = 11−00 1−00 = 110−0 10−0 10−0 = 110−0 0−1 = 10−110 0 = 10 −1−10 −11 Using the definition of the powertrain ratio to replace 25 0: 1 = 10−1− 10−1 2024 / 5917 BE2024 / 5917 -28- 1 = 10−−1 10 Considering that <0, then 1 = ||+1−||10 10 Thus, from the point of view of the design of the powertrain 1 (PU), for a determined input speed, in order to increase the ratio 5 of the powertrain 1 (for example at low speed, for mountain bike, there is a small transmission ratio) while limiting the speed 1 of the first engine 40 (for example due to physical or control limitations),One possibility is to increase the output stage ratio and decrease the input stage ratio. This possibility is used in order to obtain a wide range of maximum powertrain ratios, with a reasonable maximum rotational speed of the first motor. Beyond a limit defined by the design choices, at low gear ratios, the speed of the first motor is opposite to the speed at high gear ratios. This sub-mode of operation (a) of the first mode of operation implies that the first motor behaves as a generator. The speed of the first motor is directly determined by the desired gear ratio, which conditions the power, negative in this case. Indeed, the first motor 40 absorbs mechanical power to convert it electrically (with positive torque and negative speed). Consequently, 20 for a given level of assistance,The second motor 50 provides both the assistance power and the power regenerated by the first motor 40. The second motor 50 may need to be oversized to deliver this power. Furthermore, if the powers of the first motor 40 and the second motor 50 partially compensate each other, the losses, proportional to the power of each motor, add up (a superfluous loss consisting of the loss on the energy regenerated by the first motor 40 as well as an additional loss related to the overcompensation of the second motor 50). The more negative the power regenerated by the first motor 40, the higher the losses, which can lead to a reduction in range and significant heating. 30 2024 / 5917 BE2024 / 5917 -29- In the first operating mode, the ratio (for example, the (respective rotational speeds relative to the non-rotating body) between the output body and / or wheel, and the input body is constantly adjusted. For example,The control unit 22 can be configured to control the speed ratio accordingly. The objective may be to maintain the reference pedaling speed.5 Also, the control unit 22 can be configured to determine and / or control a torque of the second motor in order to maintain a predefined level of assistance (ratio between input power and output power). To avoid a reduction in range and significant overheating, the process may include a second operating mode (corresponding to a second operating mode in which the powertrain is configured). In the second operating mode, the cyclist provides torque to the pedals 21 and the control unit 22 determines only a torque (or current) control command, corresponding to an assistance level, for the first motor 40 and / or the second motor 50 and controls this motor(s) 15 according to this command. The speed ratio between the output body 13 and the input body 11 is mechanically fixed.in the senses where the speed ratio is not defined and is variable through the differential system, possibly thanks to the existence of one or more freewheels.20 More specifically, in the second operating mode, the motion can be transmitted from the input body 11 (the crankset 21 in Figure 3) to the output body 13 (the output plate in Figure 3) through the first freewheel 26, and possibly the second freewheel 30, and possibly through the reducers 28, 32, 34. The speed ratio between the output body 13 and the input body 11 is therefore mechanically fixed. In this second operating mode,The input body 11 is coupled to the second input element 102 (the ring in Figure 3) by the first free wheel 26, and the input body 11 is coupled to the output body 13 by the first free wheel 26 and by the second free wheel 30. The first free wheel 26 and the second free wheel 30 are in operation (i.e., the free wheels are locked and transmit torque). This allows the power of the first motor 40 to be transmitted to the output body 13 by the differential system 10 via the second input 102 (the ring in Figure 3). Thus, the input body 11 also drives the second element input 102 of the differential system 10. Since the output element 103 (the satellite carrier in Figure 3) is also driven by the closure of the second freewheel 5 30, the first input element 101 (the pinion shaft in Figure 3) is also in motion. Furthermore, in this second mode of operation, thanks to the configuration of the transmission components and in particular, the freewheels within the powertrain,It is planned to assist the cyclist with the first motor 40 and / or the second motor 50. Indeed, the second motor 50 is mounted directly in parallel with the input body 11 or connected to the output body 13 so that torque can be introduced by the cyclist and / or the second motor 50 (through their respective transmissions). As for the first motor 40,It is possible to use the first motor 40 to provide torque assistance to the cyclist. 15 The assistance provided by the first motor 40 can be achieved without using the differential system 10 as a speed variator and without changing the speed ratio of the powertrain. The energy is divided within the differential system 10, partially output by the second input element 102 and by the output element 103. 20 The torque equilibrium equation at the first input element 101 of the differential system 10 is: 1 = 11 1 The torque equilibrium equation at the second input element 102 of the differential system 10 is: 25 2 = 21 2+1−21 1 2 = −2−21 21+1 2024 / 5917 BE2024 / 5917 -31- The torque equilibrium equation at the second input element 102 of the Differential system 10: =31+21 2 15 The equilibrium equation for the differential system 10: 1=−12=−1 −13 Combining the four equations, we obtain: 0=13+−12+122+1210 0=−−11+11+122+12 0=−−11 1+ 111+122+12 0=1 12−−1 11+1 222 +1 21 Thus,We observe that a torque can be obtained at the output body 13 in 15 by introducing a positive torque on the input body 11 (corresponding to the torque supplied by the cyclist at the crankset), a positive torque by the second motor 50, a negative torque by the first motor 40 and a negative speed of the first motor 40. In the second mode of operation, the assistance of the cyclist can be done with the second motor 50 and / or can be done with the first motor 4020 supplying a negative torque and a negative speed, which allows to introduce a positive power. The advantage of the second operating mode is that it is possible to assist with one or the other motor, or even both simultaneously, depending on the operating point and in order to optimize the overall efficiency and / or thermal state of the powertrain while preserving battery autonomy. Compared to the first operating mode, at low gear ratios, the efficiency is better. Indeed, no motor generates energy injected into the system elsewhere. Thus,The process and powertrain according to the invention make it possible to cover a wide range of speed ratios. These wide ranges are covered while optimizing the overall efficiency and / or thermal state of the powertrain while preserving battery range. The control of the second operating mode can be based on different steps. Optionally, the control can include an estimation of the mass of the vehicle and the rider. The control can also include the calculation of the total torque required, the calculation of the assistance torque (fraction of the total torque), and the distribution of the assistance torque between the first motor and the second motor. Regarding the estimation of vehicle and cyclist mass, it is possible to measure or estimate this data using several methods. These include taking into account the average value for cyclists in a target group, or inputting the cyclist's mass by the cyclist themselves through an interface.by a measurement of the deformation of an element subjected to the effort associated with the weight of the cyclist (for example, such as the deformation of a part of the frame, the deformation in the saddle, the travel of a possible suspension, etc.), by a calculation of the mass by solving the equation of dynamic equilibrium (Newton's law) on the vehicle-cyclist assembly and / or by a combination of the aforementioned methods. Regarding the estimation of the mass of the vehicle-cyclist system, the estimate can be calculated by solving the dynamic equilibrium equation (Newton's law) on the vehicle-cyclist system. Such an estimation is made in particular during the first operating mode, with a view to a transition to the second operating mode (and considering that the mass does not change). Simplified definition: =30 2024 / 5917 BE2024 / 5917 -33- With -F(force) represents the forces on the system -m(mass) represents the inertia of the system -a(acceleration) represents the kinematics. More precisely,the inertia of the vehicle-cyclist assembly is not only due to their mass but also to a contribution from the inertia of rotation of the parts in circular motion, the wheels for example. This equivalent inertia is noted em*. The forces acting on the bicycle and cyclist are multiple: - The torque of the transmission applied to the wheel (Tw)10 - Gravity - Aerodynamic drag losses of the bicycle and cyclist - Friction losses within the mechanics - Rolling resistance, i.e., losses within the tires due to deformation (hysteresis cycles),15 - Damping losses of the suspension if the bicycle is equipped with it - Other types of losses Thus, we can write (in the frame of reference associated with the cyclist's direction) −−=* With20 -rw: the radius of the drive wheel -g: the gravitational acceleration -α: the slope of the hill -Flosses: the sum of the forces of losses -m*: the inertia of the bicycle and cyclist group25 In the first mode of operation,The dynamic equilibrium equation is solved at regular intervals. The kinematics (in particular velocity and acceleration) is estimated directly and indirectly using the inertial measurement unit (accelerometer, gyroscope and / or inclinometer) implemented on the vehicle, potentially in the powertrain. The transmission forces are known through the torque control strategy of the vehicle. Other forces on the vehicle are estimated or neglected. In simplified terms: =5 In detailed terms: *=−− Thus, it is possible to calculate an estimate of mass via an iterative calculation. For reasons of accuracy, it is preferable to perform the calculation -During a sharp acceleration10 -When crossing terrain with a low / zero gradient (unless a good slope estimate is available) -When losses are low (beyond a critical speed to avoid proportionally significant rolling resistance,and lower than another critical speed to avoid aerodynamic losses).15 The estimation of inertia can be performed during certain periods when these conditions are more closely respected. In some cases, losses and the effect of gravity can be neglected. A robust mass estimate is obtained by filtering the signal from the point estimate. This value is stored in memory. Regarding the calculation of the total torque required at the output of the powertrain unit (TDU). It is possible to determine the total torque required to obtain the desired behavior in several ways: -By choosing a fixed torque,determined by design - By calculating a torque that depends on the speed or acceleration of the bicycle25 - By calculating a torque that depends on the speed of the pedals - By calculating a torque that depends on the slope 2024 / 5917 BE2024 / 5917 -35- - By calculating a torque that depends on the torque of the cyclist (assistance proportional to pedaling torque is sought by electric bicycle users because it is more pleasant and more natural) - By solving the dynamic equilibrium equation (Newton's law) on the vehicle-cyclist system5 - By a combination of these methods mentioned above - By using a neural network or artificial intelligence that can use the same input data as the previous methods (or any other available input data) and which is trained elsewhere.10 The cyclist's torque can be estimated or measured: -By measuring the deformation of one or more parts of the transmission's kinematic chain. For example, a strain gauge torque sensor can be used on a specific part. According to another method,The torque of the cyclist on the crankset is estimated, on the one hand, by measuring the deformation of a section of the kinematic chain of the powertrain traversed by the cyclist's effort, by comparing the position at the two ends of this section, and, on the other hand, by the stiffness of this section determined beforehand - By measuring the deformation of a support part (direct or indirect) of the transmission chain provided that it is stressed during pedaling by the cyclist - By measuring the acceleration of the crankset relative to the input body - By applying a positive and increasing torque to the first motor until the second free wheel opens,so as to calculate the dynamic equilibrium 25 on the differential system - By measuring the amplitude of a sinusoidal signal corresponding to the speed of the pedals (the constant part of the speed coming essentially from the assistance and the cyclically variable part coming essentially from the pedaling effort of the cyclist) 30 - By a combination of the aforementioned estimates and measurements. 2024 / 5917 BE2024 / 5917 -36- In a particular embodiment, the estimation of the pedaling torque (on the crankset) by measuring the deformation of the transmission is implemented by calculation as a function of the position of the crankset axle position sensor and the position of the second motor. More precisely, the estimator of the estimated pedaling torque could be: 5 = 22 1− , a coefficient, is defined as a function of the elasticity of the transmission, notably taking into account the elasticity of the transmission from the crankset axle to the axle of the second motor,but also and especially of the first free wheel F1. It is also possible to imagine more complex laws also taking into account the position sensor of M1 as well. The slope can be estimated or measured: -By the information received by an inclinometer -By the information received from an inertial measurement unit -By the combination of the position determined by the GPS system (or equivalent) and map data (spatial derivatives of altitude) -By the combination of data received from a barometric altimeter combined with the speed of the bicycle -Etc. -By a combination of the aforementioned estimates and measurements.20 The total torque estimate via Newton's law can be obtained as follows. The calculation of the assistance torque in the second operating mode is based on the same equation as the mass estimation in the first operating mode, but, this time, the mass is considered known and we seek the torque to be applied. The system mass is considered25 as unchanged compared to the mass of the first operating mode,There is no reason for it to have changed significantly. The value recorded during the first mode is therefore an excellent approximation. This allows us to calculate the necessary torque: =*++30 2024 / 5917 BE2024 / 5917 -37- In one embodiment, acceleration and losses can be considered negligible. We therefore obtain: = , the slope of the slope, is obtained by estimation based on measurements from the inertial measurement unit. The torque is transmitted from the powertrain to the 5th wheel, possibly through the downdrive: = If the third free wheel 14 (optional) is in motion, which is generally the case when the second operating mode is active. Concerning the calculation of the assistance torque, this is done mainly on 10 based on the total torque: @= The powertrain torque is the sum of the assistance torque and the cyclist's torque both evaluated at the output: @=@+@15 In one embodiment, the assistance torque is a function of the cyclist's torque and possibly,may be proportional to the cyclist's torque: @=@ Regarding the distribution of the assistance torque between the first motor 40 and the second motor 50, the torque at the output of the powertrain is a 20 combination of the cyclist's torque and the torque supplied either by the first motor 40, or by the second motor 50, or by the torques of these two motors 40 and 50 in a proportion chosen by a distribution method. The objective of the distribution method may be: - To increase the overall efficiency of the powertrain 25 - To move one or the other of the components and organs (electronics, engine, transmission, etc.) according to their condition, thermal for example - To minimize noise, vibrations or any other undesirable effects of the system's operation - To get rid of a defective component or organ 30 - Etc. 2024 / 5917 BE2024 / 5917 -38- -By combining the aforementioned objectives. In the second mode of operation, the ratio (for example, of the respective rotational speeds with respect to the non-rotating body - for example,(between the output body and the input body) is continuously the minimum ratio. For example, the control unit 22 can be configured to control the transmission ratio accordingly. This can be advantageous, for example, for climbing steep hills. In the event of a failure of the powertrain, a battery 25, certain component failures (or for any other reasons specific to the control strategy), the process may include a third operating mode 10 (corresponding to a third operating mode in which the powertrain is configured). In the third operating mode, the cyclist provides torque to the pedals 21 and the control unit 22 does not provide a driving command to the first motor 40 or the second motor 50. This allows the cyclist to propel the vehicle even when the powertrain 15 is no longer active. More specifically, in the third operating mode,The kinematics are identical to the second mode of operation. The movement can be transmitted from the input body 11 (the pedal assembly 21 in Figure 3) to the output body 13 (the platform in Figure 3) through the first free wheel 26, the second free wheel 30, and possibly through the reducers 28, 32, 34. In this case, the first free wheel 26 and the second free wheel 30 are in motion to transmit the cyclist's power to the output body 13. Thus, the input body 11 also drives the second input element 102 (the ring gear in Figure 3) of the differential system 10. Since the output element 103 is also driven by the closing of the second free wheel 30, the first input element 101 (the pinion shaft in Figure 3) is also in motion. In these modes, the two motors are not controlled and their torque is therefore zero (losses are neglected). In this third operating mode,The powertrain 30 provides no assistance. The torque supplied by the first motor 40 and the second motor 50 is zero. The powertrain also does not control the transmission ratio. The powertrain ratio is mechanically fixed and determined by the ratio of the optional reduction gears 32, 34. The table below summarizes the three operating modes, as well as the speed, torque, and power sign of the rider, the first motor 40, and the second motor 50. A "0" means that the motor is inoperative. Mode Sub-Mode Circ.Cy M40 M50 Function VCP VCP VCPRA 1 (a) PM40 <Passist+++-+-+++Cvt oui (b) PM40<Passist+++++++++ PM40> Passive+++++++-- 2 M40+++--+000 Fix.M50+++000+++ M40+50+++--++++ 3+++000000no With: -Mode: 1, 2, 3: the first, second and third operating modes described10 -Circ.: the circumstances of the sub-Mode -Cy: Cyclist -M40: First motor40 -M50: Second motor50 -V: Speed15 -C: Torque -P: Power -R: Ratio -A: Assistance -Cvt: Continuously Variable Transmission20 -Fix.: Fixed. In addition,The first operating mode can be divided into two sub-modes ((a) and (b)). The power of the powertrain 1 (DU) is equal to the sum of the assistance power (Passist) and the rider's power (neglecting losses). The assistance power corresponds to the sum of the powers of motors 40 and 50. Thus, sub-modes (a) and (b) of the first operating mode (2024 / 5917 BE2024 / 5917 -40-) vary depending on whether the power of the first motor 40 (PM40) is greater or less than the assistance power (Passist). The second operating mode can also be divided into three sub-modes (M40, M50, M40+50) depending on whether the first motor 40 is operating. only that the second motor 50 is operational, only that the first motor 540 and the second motor 50 are operational. Other modes of operation may be envisaged. In certain embodiments and / or certain modes of operation, the ratio (for example,The respective rotational speeds (with respect to the non-rotating body) between the output body and the input body can be selected by the cyclist or by software (e.g., the control unit) from a set of predefined (discrete) ratio values. For example, the control unit can be configured to control the transmission ratio accordingly. In this case, the step-by-step ratio change is emulated because the selected ratio values ​​are virtual speed ratios. In some embodiments and / or operating modes, the powertrain is configured to apply torque at the output body even if the cyclist gives virtually no (or no) power at the input body, which can, for example, allow the cyclist to move the vehicle with little effort, for example when walking. a bicycle. In certain embodiments and / or operating modes, the powertrain is configured to apply a negative (braking) torque to the output shaft. In this case,The powertrain is configured to absorb kinetic energy. The powertrain can, for example, be configured to supply the recovered energy to the battery, for example to store this recovered energy. The invention also proposes a step for identifying the condition(s) that trigger the transition from one mode to another, in particular between the first operating mode and the second operating mode. This step starts a transition with the aim of: 2024 / 5917 BE2024 / 5917 -41- -Increasing the overall efficiency of the powertrain -Moving one or the other of the components or organs (electronics, engine, transmission, etc.) according to their state, thermal for example -Minimizing noise,Vibrations or any other undesirable effects of system operation 5 - Overcoming a defective component or organ - etc. - By a combination of the aforementioned goals. The transition from one mode to another is preferably done smoothly and allows, in particular, for continuous adaptation of the torque and speed between the operating point 10 of the initial mode and that of the terminal mode. The adaptation of the operating point in terms of speed and torque can be done sequentially, starting with the speed or the torque, or simultaneously. =2+1−1 =2+1−115 With and, the transition coefficients: -From the first mode to the second mode: ∶0→1 ∶0→1 -And conversely from the second mode to the first mode20 ∶1→0 ∶1→0 In one embodiment, the transition between the first and second modes is carried out first by an adaptation of the transmission ratio and then by an adaptation of the torque. In one embodiment, the transition25 between the second and first modes is carried out first by an adaptation of the torque and then by an adaptation of the transmission ratio. In one embodiment,The transition coefficients can evolve continuously between their extreme values ​​by more or less regular functions (i.e., differentiable more or less indefinitely) and over more or less long time intervals. The length of the transition intervals is chosen to ensure a pleasant transition (without perceived shock) on the one hand, while ensuring the responsiveness of the process and the vehicle on the other. Within the framework of this document, the normal direction of pedaling is the direction of rotation of the pedal axle that corresponds to a forward movement of the pedal vehicle. Due to the couplings in the powertrain, in the first operating mode, the components of the powertrain will preferably each have a direction of rotation that corresponds to this normal direction of pedaling (corresponding to mode 1(b) with PM40,