Motorized and self-balancing trailer

Abstract

The invention relates to a trailer comprising a loading platform (1), a wheel assembly (2a), and a hitch (4a) carried by a connecting arm (4) for coupling to a tractor, said trailer being equipped with an electric motor powered by batteries, characterized in that said motor comprises motors which are, on the one hand, coupled to each of the wheels (2a) to drive them independently and which are, on the other hand, controlled by a computer associated with at least one level sensor measuring the angle (A) of inclination of said platform to correct its level and maintain it in equilibrium in a horizontal plane automatically and regardless of the slope (B). (Fig. 1)

Description

Title of the invention: Motorized and self-balancing trailer

[0001] The invention relates, in general, to the field of urban mobility and, more particularly, to towed trailers used for the transport and delivery of goods over a short distance.

[0002] The invention relates more specifically to a motorized and self-balancing trailer capable of being attached to a cycle (bicycles, mopeds, scooters or motorized bicycles) or to a light vehicle.

[0003] In the context of urban transport logistics, and in particular for the transport and delivery of goods and products to customers over a short distance known as the last mile, trailers pulled by cycles or cargo bikes are frequently used today.

[0004] Such a trailer, which is described in patent application WO2011108948A1, is equipped with a propulsion system comprising a drive mechanism associated with a controller of the power delivered to this mechanism in response to a signal which is a function of the demand on the tractor vehicle.

[0005] Furthermore, patent EP3416860B1 describes a motorized trailer equipped with means ensuring braking management according to the drawbar load and the distance between the trailer and the towing vehicle.

[0006] Patent EP3552933B1 describes, for its part, stabilizing feet for a trailer which are deployed by means of jacks.

[0007] However, the trailer embodiments described in these documents incorporate technically complex and expensive means for controlling wheel direction and trailer stability.

[0008] Thus, existing trailers do not include means capable of ensuring the management of their inclination in a simple, reliable and precise manner, which poses problems of safety and preservation of the load.

[0009] In this context, the invention aims to solve the technical problems posed by previous trailers and to overcome their shortcomings by proposing an improved, motorized and self-balancing trailer, with a better footprint when hitched behind a tractor cycle, a more economical manufacturing cost and a more compact size better suited to traffic in urban environments.

[0010] This objective is achieved, according to a first aspect of the invention, by means of a trailer comprising a loading platform, a wheel assembly and a hook carried by a connecting arm for coupling to a tractor, said trailer being equipped with an electric motor powered by batteries, characterized in that said motorization includes motors which are, on the one hand, coupled to each of the wheels to drive them independently and which are, on the other hand, controlled by a computer associated with at least one level sensor measuring the angle of inclination of said platform to correct its level and maintain it in balance in a horizontal plane automatically and regardless of the slope.

[0011] According to an advantageous feature, the trailer of the invention includes at least one force sensor coupled to said motors to impose differentiated speed changes on them while maintaining the platform's attitude

[0012] According to another advantageous feature, the trailer of the invention includes at least one steering sensor coupled to said motors to impose differentiated changes in speed and differentiated rotation speeds of the wheels in order to facilitate turning.

[0013] According to a specific embodiment, the force sensor is integrated into the link arm with the tractor, the steering sensor is arranged between the arm and the platform and the pitch sensor is mounted directly on the platform.

[0014] According to yet another feature, the trailer of the invention includes a set of jacks associated with retractable supports intended to ensure the immobilization and stability of the platform when the engines are stopped.

[0015] Preferably, these jacks are mounted at the front and rear of the platform.

[0016] Another object of the invention is a control system for the control of electric motors providing independent drive of the wheels of a mobile platform in order to ensure its automatic stabilization, characterized in that it comprises a computer coupled to a first set of sensors measuring the angle of inclination of said platform to correct its attitude, a second set of force sensors coupled to said motors to impose differentiated changes in speed in order to maintain the attitude of the platform and a third set of direction sensors coupled to said motors to impose differentiated changes in speed in order to facilitate turning.

[0017] Yet another object of the invention is a use of the control set defined above for the control of the motors of a hitched trailer.

[0018] The trailer of the invention is electrically powered by onboard batteries. The independent wheel assembly provides traction, braking, and balancing functions. The coupling arm for attaching the trailer to the bicycle incorporates one or more essential sensors and thus provides the required steering, acceleration, or braking information.

[0019] The invention makes it possible to significantly reduce the complexity and bulk of existing motorized and towed trailers and, consequently, to limit their manufacturing and maintenance costs.

[0020] Furthermore, in view of the significant development of urban mobility and taking into account the new environmental constraints advocating the prohibition of the circulation of vehicles with internal combustion engines, the reduction of roads, or even the banning of motor vehicles in city centers, the trailer of the invention proves to be particularly well suited to offer a solution to the current problem of last mile delivery in urban areas.

[0021] Other features and advantages of the invention will become apparent from the following description, with reference to the accompanying figures, for which:

[0022] [Fig. 1] is a schematic side view of one embodiment of the trailer of the invention on an inclined track.

[0023] [Fig.2] is a schematic top view of the trailer of [Fig.1] in a turn.

[0024] [Fig.3] is a schematic side view of the trailer of [Fig.1] at rest.

[0025] For clarity, identical or similar elements are identified by symbols identical reference points across all figures.

[0026] Naturally, the embodiments of the trailer of the invention schematically illustrated in the figures above and described below are given only by way of non-limiting examples. It is explicitly provided for in the scope of the invention that different embodiments can be proposed and combined to create others.

[0027] It is emphasized that all features, as they appear to a person skilled in the art from reading this description, the figures and the associated claims, even if in practice they have only been described in relation to other specific features, both individually and in any combinations, can be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that the technical context makes such combinations impossible or meaningless.

[0028] The invention relates to the general field of logistics for the transport and delivery of goods in urban areas, over a short distance arbitrarily referred to as the last mile.

[0029] The invention relates more specifically to a trailer comprising, in a traditional manner and as illustrated by [Fig.1], an open or closed loading platform 1, a wheel assembly 2a, 2b mounted on either side of the platform and a hook 4a carried by a connecting arm 4 for coupling with a tractor (not shown) which is preferably a cycle.

[0030] This trailer is also equipped with an electric motor (not shown) powered by batteries mounted on platform 1 and which is intended to facilitate the traction of the trailer. Indeed, this traction can prove difficult, in particular, when the weight of the load supported by the platform is significant.

[0031] The invention seeks to make traditional trailers less complex, less expensive to produce, more compact and more easily towed while perfecting the means intended to ensure its stabilization and steering, automatically and autonomously, regardless of the inclination B and the orientation C of the road R.

[0032] For this purpose, the motorization includes motors which are coupled to each of the right wheels 2a and left wheels 2b to drive them independently and whose stator is rigidly fixed to the platform 1 while the rotor is fixed to the wheel 2a, 2b.

[0033] According to the invention, these motors are further controlled by a computer associated with at least one sensor measuring the angle A of the platform relative to the vertical in order to correct its attitude and maintain it in equilibrium in a horizontal plane regardless of the inclination B of the slope, as illustrated by [Fig. 1]. The invention thus consists of equipping the motorized wheels with a pitch stabilization function which, thanks to the attitude sensor, ensures that the trailer finds its balance by itself without the assistance of an operator or the tractor.

[0034] In particular, a zero angle A between the orthogonal axis X of the platform 1 and the vertical will allow the trailer to achieve an equilibrium position that minimizes the energy required to maintain its balance. However, since this equilibrium position is likely to change during delivery operations as the platform's load is modified (lightened or weighed down), it will be continuously adjusted to reduce the electricity consumption required to stabilize the trailer. This correction will be independent of the incline B of the road slope R on which the trailer will be towed.

[0035] The trailer of the invention further comprises at least one force sensor 3 coupled to the motors to impose differentiated speed changes on them while maintaining the platform's attitude. Thus, according to the information provided by the force sensors 3 to the computer, the servo motors will drive the wheels with a positive or negative torque to accelerate or decelerate, respectively, while maintaining the optimal angular position of the trailer to ensure its stability.

[0036] If acceleration is commanded, angle A will have to increase to compensate for the tilting of the platform backwards and conversely, in case of braking, angle A will be decreased to compensate for the tilting of platform 1 forwards.

[0037] The invention also provides that the trailer includes at least one steering sensor coupled to the motors to impose changes in speed and different wheel rotation speeds in order to facilitate turning.

[0038] Indeed, depending on the value C of the angle measured by the sensor between the longitudinal axis Y of the trailer and the desired road direction R, a rotation command A different signal will be sent between the left and right motors to perform the desired turn. Thus, for example, in the situation illustrated by [Fig.2], the left motor will have to rotate faster than the right motor, or, if the trailer is stationary, the left motor will have to rotate forward while the right motor rotates in reverse in order to steer the trailer in place.

[0039] Preferably, the force sensor 3 is integrated into the link arm 4 with the tractor. The steering sensor is located between the arm 4 and the platform 1. The pitch sensor, which is used to measure the inclination A, is mounted directly on the platform 1.

[0040] The force sensor 3 consists, for example, of a strain gauge that elongates under the effect of a force or deformation, and whose elongation is measured to deduce the level of stress. The direction sensor consists, for example, of a magnetic sensor. The attitude sensor is preferably an inertial sensor incorporating an accelerometer and a gyroscope.

[0041] Each motor is equipped with additional sensors designed to determine the precise position of the platform. These position sensors are mounted between the platform and the corresponding wheel to allow for accurate control of the trailer's position.

[0042] In addition, and as illustrated in [Fig. 3], the trailer of the invention includes a set of cylinders 5 associated with retractable outriggers 5a, 5b designed to ensure the immobilization and stability of the platform when the engines are stopped during the loading or unloading phase, including when the trailer is parked on a flat or sloping road. Preferably, these outriggers 5a, 5b are mounted at the front and rear of the platform 1 and are each operated by a cylinder. However, it is possible, according to an alternative embodiment, for the outriggers to be operated by a single cylinder.

[0043] The jacks 5 are electrically controlled and powered by the on-board batteries. When the trailer is stationary, deploying the outriggers 5a, 5b cuts off the power to the motors and thus stops the rotation of the wheels, which no longer directly contribute to stabilizing the platform 1. The electrical system can then be switched off.

[0044] In the situation illustrated by [Fig.3], the trailer is stationary on a horizontal plane and the front support 5a is deployed to rest on the road while the rear support 5b is retracted, stabilization then being ensured solely by the wheels 2a, 2b and the front support 5a.

[0045] These jacks will be sized and calibrated according to the characteristics of the trailer and its payload so that the force applied to the road the support legs must ensure that the trailer cannot tip over and optionally neither move forward nor backward.

[0046] The jacks 5 and the outriggers 5a, 5b can also be used if the battery charge level is too low to properly power the motors and allow the wheels to perform their function of stabilizing the platform.

[0047] Another object of the invention is a control assembly intended for the control of electric motors ensuring the independent drive of the wheels of a mobile platform in order to ensure its stabilization in an automatic and autonomous manner.

[0048] This control unit, which can be mounted on an existing trailer platform, includes a computer coupled to a first set of sensors measuring the angle of inclination A of said platform to correct its attitude, a second set of force sensors coupled to the motors to impose differentiated changes in speed while maintaining the attitude of the platform, and a third set of steering sensors coupled to said motors to impose differentiated changes in speed in order to facilitate turning.

[0049] In the embodiment shown in the figures, the platform 1 is equipped with a two-wheel train, but it is possible to provide, without departing from the scope of the invention, that the platform includes more than two wheels, some of which would not be driven, and that the control assembly is controlled only by an even number of them located on either side of the platform.

Claims

Demands

1. Trailer comprising a loading platform (1), a wheel assembly (2a, 2b) and a hook (4a) carried by a connecting arm (4) for coupling with a tractor, said trailer being equipped with an electric motor powered by batteries, characterized in that said motor comprises motors which are, on the one hand, coupled to each of the wheels (2a, 2b) to drive them independently and which are, on the other hand, controlled by a computer associated with at least one attitude sensor measuring the angle (A) of inclination of said platform to correct its attitude and maintain it in balance in a horizontal plane automatically and regardless of the slope (B), the trailer further comprising at least one force sensor (3) coupled to said motors to impose differentiated changes in speed on them while maintaining the attitude of the platform (1),at least one steering sensor coupled to said motors to impose changes in engine speed and differentiated wheel rotation speeds in order to facilitate cornering, the force sensor (3) being integrated into the link arm (4) with the tractor, the steering sensor being positioned between the arm (4) and the platform (1) and the pitch sensor being mounted directly on the platform (1).

2. Trailer according to claim 1, characterized in that it comprises a set of jacks (5) associated with retractable supports (5a, 5b) intended to ensure the immobilization and stability of the platform (1) when the engines are stopped.

3. Trailer according to the preceding claim, characterized in that said supports (5a, 5b) are mounted at the front and rear of the platform.

4. Control assembly for the control of electric motors providing independent drive of the wheels (2a, 2b) of a mobile platform (1) in order to ensure its automatic stabilization, characterized in that it comprises a computer coupled to a first set of sensors measuring the angle of inclination (A) of said platform to correct its attitude, a second set of force sensors (3) coupled to said motors to impose differentiated changes in speed in order to maintain the attitude of the platform and a third set of direction sensors coupled to said engines to impose differentiated changes in speed in order to facilitate cornering.

5. Use of the control assembly according to claim 4 for the control of the motors of a coupled trailer.