FIELD OF THE INVENTION

The present invention concerns an activation device for electric and/or electronic user devices and the relative activation method. The device according to the present invention can be used to allow the activation of an electric user device such as the motor of a vehicle, like an electric bicycle, an automobile, or the motor of a work instrument or tool, or a gate, a door for entrances or other, so as to allow use for an authorized user only.

In particular, but not exclusively, the activation device according to the present invention is advantageously used as an anti-theft device for electric bicycles.

BACKGROUND OF THE INVENTION

Activation devices for electric user devices are known, such as for example the electric starter motor for a vehicle, used as immobilizers or anti-theft devices. Such known devices are based on the interaction between a transponder element contained in the ignition key used, and an electronic unit of the vehicle, provided with an element for reading the transponder, which reads and processes the data received by the transponder.

An example of such an activation device is described in the US patent 5,675,490, which provides that an electronic unit and a plurality of control devices of the vehicle are connected through a communication line of the bus type to the electronic unit.

The electronic unit is in turn connected to a transponder reader, which reads at least a univocal code, memorized in the transponder of the starter key when it is inserted into a corresponding starter block. After reading the code of the transponder of the key, the electronic unit sends a reading request of a specific code to all the control devices. If one or more control devices do not respond to the request, or if the code of the key detected is different from the codes sent by the control devices, then the electronic unit prevents the activation of the various control devices and hence of the starter motor of the vehicle too.

One disadvantage of this known activation device is that it is complicated and expensive to make in low-cost vehicles such as an electric bicycle. Furthermore, this known device inhibits the use of the electric user device based on an initial comparison of specific activation codes which are not modified with every ignition inasmuch as they are memorized in a non-volatile memory both of the central unit and of the control devices. The codes could be read fraudulently, for example by means of monitoring devices of the bus line or the transponder connection, allowing to acquire the univocal code of the transponder.

Another example of an activation device for electric user devices is described in the patent application US 2009/199292. This activation device comprises a user device suitable to generate random numbers and a closing device. The authentication of the user device to enable the closing device occurs at the end of a step which provides an exchange of information between the activation device and the closing device, in which the information consists of "challenge" signals. One disadvantage of this solution is that the exchange of information uses a complex scheme, and does not allow any authentication in real time of the user device.

Another example of an activation device for electric user devices is described in the patent application US 4,509,093, which comprises a key unit suitable to generate random numbers, and a closing unit. The authentication of the key unit in the closing unit occurs in an information exchange step of the numerical type between the two.

One disadvantage of this solution is that, as explained above, the exchange of information uses a complex scheme, and does not allow a particularly speedy authentication of the user device.

One purpose of the present invention is to achieve an activation device for electric and/or electronic user devices that allows only one or more authorized users to use said user device, and that is difficult to duplicate or replicate in a fraudulent manner.

Another purpose of the present invention is to achieve an activation device in which authentication can be carried out in real time, and in which two or more processing units can generate a pseudo-aleatory signal.

Another purpose of the present invention is to achieve an activation device in which the comparison or mixing of the pseudo-aleatory signals generated by the processing units can occur simply and by using economical circuits. A further purpose of the present invention is to achieve an activation method for electric and/or electronic user devices that functions in real time, and that allows a safe activation only for users authorized to use said user devices, at the same time being simple to make.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, an activation device for electric and/or electronic user devices comprises first electronic processing means associated with the electric or electronic user device to be activated, and second electronic processing means associated with one or more users enabled to use the electric or electronic user device. The second electronic processing means are selectively connectable, during use, with the first electronic processing means in order to determine, or not, the enablement to use said electric and/or electronic user device.

According to one feature of the present invention, the first electronic processing means comprise first generator means able to generate at least a first pseudo-aleatory signal. The second electronic processing means comprise second generator means able to generate at least a second pseudo- aleatory signal.

The device according to the present invention also comprises comparison means connected on one side both to the first electronic processing means and to the second electronic processing means so as to receive the first and the second pseudo-aleatory signal. The comparison means are connected at outlet directly or indirectly to the electric and/or electronic user device to be activated and are suitable to transform, in a predetermined manner, the first pseudo- aleatory signal and the second pseudo-aleatory signal which are synchronized with each other and, in the preferential solution, represent quantities that evolve over time, in order to generate at outlet a desired electric feed signal of the basic electric and/or electronic user device. According to a preferential embodiment of the present invention, the comparison means are made with the use of a single logic gate, or a single operational amplifier, and are suitable to compare or mix the first and second pseudo-aleatory signal in real time.

Therefore, when the second pseudo-aleatory signal generated by the second electronic processing means is not compatible with the first pseudo-aleatory signal, for example because it is generated by second electronic processing means associated with a non-authorized user, the outlet signal generated by the comparison means does not allow the connected electric and/or electronic user device to be fed, thus preventing unauthorized or fraudulent use thereof.

In a first solution the electric and/or electronic user device is a direct current motor.

According to this first embodiment, the comparison means comprise at least a logic gate XOR ("exclusive OR"), or XNOR ("exclusive NOR"), directly or indirectly connected respectively at a first inlet to the first signal generator and at a second inlet to the second signal generator. The logic gate XOR or XNOR is connected at one of its outlets directly or indirectly to the electric and/or electronic user device.

In a second solution the electric and/or electronic user device is a stepper motor.

In this second solution the comparison means comprise at least a logic gate XOR and the first electronic processing means comprise, or are associated with, controller means to control the stepper motor. Auxiliary comparison means are also provided, connected on one side to the first generator means and the controller means, and on the other side connected at outlet to the XOR gate.

In this second solution the auxiliary comparison means also comprise an XOR gate.

According to another feature of the present invention, the first electronic processing and the second electronic processing means comprise, or are respectively associated with, first and second electronic memorization means, to memorize at least a corresponding user code, according to which an initial state is determined for each of the first and second means to generate a pseudo-aleatory signal. Therefore, if the specific second electronic processing means that are associated in use with the first electronic processing means do not have the same user code, the first and the second pseudo- aleatory signal generated are not "compatible" with each other, for example they are different. Their combination in the comparison means therefore determines an outlet feed signal that is not coherent or compatible with the feed actually required for the correct functioning of the electric and/or electronic user device. Vice versa, if the user code memorized is the same, then the first and second pseudo-aleatory signal are reciprocally "compatible", for example the same, so that the combination made by the comparison means determines an outlet feed signal that is actually useful, such as a continuous electric current, in order to feed and hence use the electric and/or electronic user device.

In one solution of the present invention, the first signal generator means and the second signal generator means are digital of the cryptographically strong type. Therefore, the digital signals generated are difficult to reproduce by non- authorized users, considerably reducing the possibility of effecting a fraudulent duplication of the electronic processing means.

According to another variant of the present invention, the first signal generator means and the second signal generator means comprise or are associated with a bit generator of the Blum-Blum-Shub type.

According to another variant of the present invention, at least the first signal generator means comprise a noise generator.

According to another variant, the noise generator is a thermal noise generator, such as a Zener diode.

According to a preferential solution the second electronic processing means are the smart card type, and the first electronic processing means comprise a smart card reader device.

The present invention also concerns a method for the activation of electric and/or electronic user devices in which said electric and/or electronic user device is activated respectively by means of first electronic processing means associated therewith, and second electronic processing means associated with one or more users enabled to use said electric and/or electronic user device. The second electronic processing means are selectively connected to the first electronic processing means so as to determine the enablement to use said electric and/or electronic user device.

According to one feature of the present invention, the method comprises at least a step of generating pseudo-aleatory signals, in which by means of first signal generating means associated with the first electronic processing means, a first pseudo-aleatory signal is generated and by means of the second signal generating means associated with said second electronic processing means a second pseudo-aleatory signal is generated. The pseudo-aleatory signals preferably represent electric quantities that evolve over time.

The method also comprises a comparison or mixing step, in which by means of comparison means connected respectively at inlet to the first electronic processing means and to the second electronic processing means, and at outlet to the electric and/or electronic user device to be activated, the first pseudo-aleatory signal and the second pseudo-aleatory signal are combined in real time and in a predetermined manner. At outlet from the comparison means a corresponding electric feed signal is generated which feeds the electric and/or electronic user device according to the combination of the first and second pseudo-aleatory signal.

In one solution, at least one of either the first pseudo-aleatory signal or the second pseudo-aleatory signal is pre-trans formed by means of auxiliary comparison means with a control signal of the electric and/or electronic user device.

According to another feature of the present invention, the method comprises a comparison step in which, according to the comparison between at least a user code memorized in first memorization means of said first electronic processing means and in second memorization means of said second electronic processing means, an initial state is determined for each of the first and second pseudo- aleatory signal generating means.

According to one solution, the initial state is determined by means of a "hash" processing of the user code.

According to a variant, the initial state is also determined by means of noise generating means, associated with the first electronic processing means or second electronic processing means. BRIEF DESCRIPTION OF THE DRAWINGS These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 is a block diagram of an activation device for electric and/or electronic user devices according to the present invention;

- fig. 2 is a detailed block diagram of a first form of embodiment of the activation device in fig. 1 ;

- fig. 3 is a detailed block diagram of a second form of embodiment of the activation device in fig. 1.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify common elements in the drawings that are substantially identical. It is understood that elements and characteristics of one form of embodiment can conveniently be incorporated into other forms of embodiment without further clarifications.

DESCRIPTION OF SOME PREFERENTIAL FORMS OF EMBODIMENT

With reference to the attached drawings, an activation device 10 according to the present invention is used to activate the functioning of an electric user device, in this case an electric motor 50, for example of an electric bicycle, not shown, or other type of electric vehicle. The activation device according to the present invention is used as an anti-theft device or immobilizers for the bicycle or the vehicle on which it is mounted. It is clear that the invention can also be applied on an electric work instrument or tool, or a gate, a door for entrances or other, so as to allow use for an authorized user only.

The activation device 10 (fig. 1) comprises a first processing unit 12, a second processing unit 24 and comparison means 32 connected to the electric motor 50.

The first processing unit 12, comprising a first generator 18 of pseudo-random numbers, shown in figs. 2 and 3, is connected by means of a first line of communication 14 to a first entrance 33 of the comparison means 32 for the transmission of a first sequence of data suitable to allow the activation of the motor 50. In particular, the first generator 18 of pseudo-random numbers transmits on the first line of communication 14 to the comparison means 32 a first sequence of pseudo-random numbers, as will be described in more detail hereafter.

Advantageously the first processing unit 12 is integrated onto the motor 50 or, for example, on the electric bicycle or vehicle provided with the electric motor 50, so as to prevent possible fraudulent actions that allow to overcome the activation control of the motor 50 achieved by the device 10.

The first processing unit 12 is also selectively connectable by means of a data bus 36 to the second processing unit 24 to allow a reciprocal data exchange as will be explained in more detail hereafter. The first line of communication 14 is a line of communication of a known type, for example digital, such as a high speed synchronous serial line, or other suitable line for transferring digital data.

The second processing unit 24 is selectively connectable by means of a second line of communication 26 to a second entrance 34 of the comparison means 32 and, by means of the data bus 36, to the second processing unit 24. In one form of embodiment the second processing unit 24 is a microchip unit such as a smart card of a known type, which can be inserted in a housing slot, or smart card reader, not shown, in turn connected to the second processing unit and the comparison means 32. The reading slot is suitably disposed for example in the frame of the bicycle, the vehicle or other type of electric and/or electronic user device to be activated.

In particular the second processing unit 24 comprises a second generator 29 of pseudo-random numbers, shown in figs. 2 and 3, whose output data are transmitted to the second line of communication 26. The second generator 29 of pseudo-random numbers transmits, on the second line of communication 26 to the second entrance 34 of the comparison means 32, a first sequence of pseudo- random numbers as will be described in more detail hereafter.

The second line of communication 26 is similar to the first line of communication 14 and advantageously has the same data transmission speed.

The second processing unit 24 is also selectively connectable directly, when inserted into the slot, with the first processing unit 12 by means of a data bus 36. The data bus 36 is of the serial type, or other known type, to allow a reciprocal initial exchange of data and to define an initial synchronization during which the same initial functioning state is defined for both the processing units 12, 24.

The comparison means 32, also of a known type, effect a transformation, such as a combination, or comparison, or mixing of the data received at the entrances 33, 34, based on a predetermined transfer function, or on a logic function on the bits entering, as will be described hereafter. The comparison means 32 then transmit to an exit 38 a single output data sequence based on the transformation of the sequences of input data, suitable to activate or not the motor 50 according to the actual sequences of data received at entrance.

Hereafter we shall refer to two forms of embodiment, one for each type of motor 50 to be activated, in this case a continuous current motor and a stepper motor. It is understood that these forms of embodiment must not be understood as restrictive, and that a person of skill in the art shall be able to achieve other forms of embodiment of the activation device according to the present invention depending on the specific type of electric and/or electronic user device to be activated.

With reference to fig. 2, a first form of embodiment is shown of an activation device 10 which in this case is suitable to activate a continuous current motor 50a.

In this form of embodiment, the first processing unit 18 comprises a first microprocessor 13 provided with a first memory 15, for example ROM or other memory of the non-volatile type, in which, during the programming of the microprocessor 13, a univocal code is memorized, for example a password string, to identify a specific user authorized to use the bicycle. Advantageously, the first ROM memory 15 is "masked" in reading, so as to prevent the data contained therein from being read, for example connecting externally to its communication or programming gates. It is understood that several univocal codes can be memorized in the first memory 15, each one associated with a different user authorized to activate the electric and/or electronic user device.

The first microprocessor 13 is also connected by means of a first command line 16 to the first signal generator 18, such as an actuation or enablement entrance, not shown in the drawings.

The second processing unit 24, similarly to what is described above, comprises a second microprocessor 25 provided with a second memory 27, for example ROM non-volatile, in which, during the programming of the microprocessor, the same univocal code is memorized as is memorized in the first memory 15. Advantageously, the second ROM memory 27 is also "masked" in reading. The second microprocessor 25 is also connected by means of a second command line 30 to the second signal generator 29, such as for example an actuation or enablement entrance, not shown in the drawings.

The first 18 and the second 29 generator of pseudo-aleatory signals can be of any type whatsoever, suitable to generate a suitable digital sequence of bits in pseudo-random manner. In one form of embodiment the signal generators 18, 29 are cryptographically strong digital generators, such as for example Blum-Blum- Shub type generators. It is understood that the signal generators 18, 29 can be of any known type.

The comparison means 32 are advantageously made by means of a logic gate of the XOR type, which emits on its exit 38 a sequence of digital values according to the value of the entrances, in particular transferring a "logic one" when the entrance values 33, 34 are different, or a "logic zero" when the entrance values 33, 34 are the same.

Using a simple logic gate to achieve the comparison means 32 entails a series of advantages: real time processing of the signal, inexpensive circuit and the possibility of miniaturizing the latter, with consequent reduction in consumption and reduction in space occupied.

The exit 38 of the comparison means 32 is in turn connected to a power stage 40, which converts the sequence of digital data at input, typically in a range from 0V to 5V, into an electric feed signal at exit, suitable to feed the continuous current motor 50a.

The activation device 10 described in the first form of embodiment functions as follows.

When the second processing unit 24 is inserted into the corresponding slot of the electric bicycle, the second microprocessor 25, suitably fed by means of a feed line not shown in the drawings, is connected by the data bus 36 to the first microprocessor 15 of the first processing unit 12.

Subsequently, the two microprocessors 13, 25 carry out a predetermined recognition and reciprocal synchronization data exchange in which they verify the validity of the univocal code, that is, the password memorized in the respective memories 15, 27. Advantageously the password is processed by each microprocessor 13, 25 by means of a hash function or algorithm or other cryptographic function of a known type.

According to one form of embodiment, the first microprocessor 13 transmits to the second microprocessor 25 exclusively settings on the initial state and the synchrony, without using the password memorized. Based on these settings, the first generator 18 and the second generator 29 generate the respective sequences of bits. Advantageously, according to this last form of embodiment, the synchronization between, and the setting of the initial state of the two generators 18 and 29 occurs quickly, and with a minimum exchange of information.

If the password memorized in each memory 15, 27 coincides, that is, if the second processing unit 24 is that of a user authorized to use the bicycle, the initial state of each signal generator 18, 29 is the same and the sequence of bits generated by them has the same initial generation conditions. The two respective digital sequences generated and transmitted through the first line of communication 14 and the second line of communication 26 are inverse with respect to each other, that is, when on the first line of communication 14 there is a "logic one", on the second line of communication 26 there is a "logic zero", and vice versa. The digital sequence at exit 38 of the comparison means is therefore a substantially continuous digital sequence of "logic ones" which feeds the power stage 40 at entrance, which in turn feeds the connected motor 50a with an electric feed tension substantially continuous over time.

According to a possible variant of the present invention, the comparison means 32 comprise a logic gate XNOR, and the logic values of the respective digital sequences generated and transmitted through the first line of communication 14 and the second line of communication 26 coincide instant by instant.

Vice versa, if the passwords do not coincide, for example when an unauthorized smart card or second processing unit 24 is inserted, the initial states of the signal generators 18, 29 do not coincide and therefore the corresponding digital sequences transmitted to the entrances 33 and 34 are not, instant by instant, identical. This means that the exit signal toward the power stage 40 is a pseudo-random combination of logic "zeroes" and "ones", which does not allow to obtain, at exit from the power stage 40, an electric tension suitable to feed the motor 50a correctly.

It is understood that in some forms of embodiment the power stage 40 can advantageously be associated with a tension variator, not shown in the drawings, for the fine tuning of the actual feed tension of the motor 50a so as consequently to adjust the speed of rotation of the motor and therefore the speed of the electric bicycle, or in general the electric user device, to a desired value.

With reference to fig. 3, a second form of embodiment of an activation device 1 10 is shown which in this case is suitable to activate a stepper motor 50b.

The second processing unit 24 is substantially identical to the one described in the first form of embodiment.

The device 1 10 also comprises a first processing unit 1 12, which in addition to the unit 12 in the first form of embodiment previously described, also has a stepper controller 19 and an XOR logic gate 21.

The stepper controller 19, of a known type used to command stepper type motors, is connected at an entrance by means of an auxiliary command line 17 to the first microprocessor 13 and at its exit 20 to a first entrance 22 of two entrances of the XOR gate 21. The XOR gate 21 is in turn connected to a second entrance 23 of its two entrances to the first line of communication 14 of the first generator 18.

The first 1 12 and the second processing unit 24 are also connected in a substantially identical manner by means of the data bus 36 as described for the first form of embodiment.

The activation device 1 10 described in the second form of embodiment functions as follows.

The initial exchange of data between the microprocessors 15, 25 is substantially identical to what was described before, and also the determination of the initial state of the processing units 1 12, 24, that is, the relative generators, and will therefore not be repeated here. If the password memorized in the memories 15 and 27 is the same, that is, the user who has to use the bicycle, or other vehicle or user device, is actually authorized, the digital sequences transmitted on the first line of communication 14 and on the second line of communication 26 are identical instant by instant.

In turn, the sequence at exit from the XOR gate 21 is combined in the comparison means 32 with the digital sequence produced by the second processing unit 24 and therefore, the sequence at exit 38 from the comparison means 32 is the same sequence emitted by the stepper controller 19, which is used to activated the power stage 40 and therefore the motor 50b connected thereto.

Vice versa, if the passwords do not coincide, for example when an unauthorized smart card or second processing unit 24 is inserted, the initial states of the signal generators 18, 29 do not coincide and therefore the sequence at exit 38 from the comparison means 32 is different from the sequence emitted by the stepper controller 19, which entails an exit signal to the power stage 40 which is not suitable to feed the motor 50b correctly.

According to a variant, the activation device according to the present invention comprises at least a noise generator 23, connected for example to the first microprocessor 13 of the first processing unit (figs. 2, 3). The noise generator 23 may be of a known type, such as, to give a non-restrictive example, a Zener diode, such as to determine an initial state for the signal generators that is actually aleatory and thus to determine a pseudo-aleatory sequence of bits which is different every time the device 10 is started. This allows to make the device 10 more secure and to make the data sent on the line of communication 14, 26 substantially inaccessible.