Vehicle guidance system and corresponding method

1. A guidance system for a follower vehicle, suitable for guiding the follower vehicle such that the follower vehicle follows a leader, the guidance system comprising:

at least two distance measuring devices designed to be carried by the follower vehicle, each being suitable for measuring a distance from a reference point of the follower vehicle, associated with a respective one of the at least two distance measuring devices, to the leader, the reference points being spaced apart from one another; and

a computing device, programmed to:

deduce a position of the leader relative to the follower vehicle from the distances measured by the at least two distance measuring devices, and

guide the follower vehicle such that the follower vehicle follows the leader based on the deduced position,

wherein each of the at least two distance measuring devices comprises a wired sensor comprising a cable having an end for connecting to the leader, a return winder for the cable kept stretched, and a member for measuring a length of unwound cable.

2. The guidance system as recited in claim 1 wherein the reference points comprise at least two reference points aligned with one another in a plane substantially parallel to a rolling plane of the follower vehicle.

3. The guidance system as recited in claim 1 wherein the reference points comprise at least three reference points that are not aligned with one another, there being three distance measuring devices.

4. The guidance system as recited in claim 1 wherein the computing device is programmed to compute a relative speed of the leader with respect to the follower vehicle from the measured distances.

5. The guidance system as recited in claim 1 further comprising an automatic pilot system for driving the follower vehicle as a function of the position of the leader deduced by the computing device.

6. The guidance system as recited in claim 1 wherein one or more of the at least two distance measuring devices further comprise a transmitting beacon, designed to be carried by the leader, suitable for transmitting a wave, and each distance measuring device comprises a member for receiving the wave, a chronometer suitable for measuring a duration between a wave transmission moment by the transmitting beacon and a wave reception by the receiving member, and wherein the computing device is programmed to deduce the distance of the transmitting beacon from the receiving member from the measured duration.

7. The guidance system as recited in claim 6 wherein the wave is an ultrasound wave.

8. A convoy comprising: the leader, the follower vehicle and the guidance system as recited in claim 6 , wherein the transmitting beacon is carried by the leader and each distance measuring device is carried by the follower vehicle, the follower vehicle being driven as a function of the position of the leader deduced by the computing device.

9. A vehicle comprising the guidance system as recited in claim 1 , wherein the vehicle is the follower vehicle and is driven as a function of the position of the leader deduced by the computing device.

10. A method for guiding a follower vehicle, comprising:

measuring, with a first measuring device, a first initial distance between a first reference point of the follower vehicle and a leader, and, with a second measuring device, a second initial distance between a second reference point of the follower vehicle, spaced away from the first reference point, and the leader;

deducing, by a computing device, an initial position of the leader with respect to the follower vehicle, as a function of the measured initial distances;

moving the leader relative to the follower vehicle;

measuring, with the first measuring device, a first modified distance between the first reference point and the leader, and, with the second measuring device, a second modified distance between the second reference point and the leader;

deducing, by the computing device, a modified position of the leader with respect to the follower vehicle, as a function of the measured modified distances; and

guiding the follower vehicle such that the follower vehicle follows the leader based on the deduced modified position,

wherein each of the first and second measuring devices includes a wired sensor comprising a cable having an end for connecting to the leader, a return winder for the cable kept stretched, and a member for measuring a length of unwound cable.