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US 12,617,408 B2Granted
Motor vehicle and method to detect a parameter associated with a superficial condition of the road surface
AssigneeFerrari S.P.A.
InventorsGiovanni Sartoni, Matteo Montirosi, Ugo Sitta
Life of this patent
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Abstract
A motor vehicle comprising a body defining a passenger compartment, a plurality of wheels; and a sensor designed to detect a parameter associated with a superficial condition of a road surface; the sensor comprises, in turn, an emitter configured to emit a first laser signal towards a road surface; and one or more single-photon avalanche diodes configured to detect a second laser signal corresponding to the reflection of the first laser signal against said road surface.
Claims11
A motor vehicle (1) comprising:
- a body (2) defining a passenger compartment (3);
- a plurality of wheels (4, 5);
- and
- a sensor (10) designed to detect a parameter associated with a superficial condition of a road surface (16);
- said sensor (10) comprising, in turn:
- an emitter (15) configured to emit a first laser signal (R) towards the road surface (16);
- a plurality of single-photon avalanche diodes (SPADs) (11a, 11b, 11c) configured to detect second laser signals (S, T, U) corresponding, in use, to a reflections of the first laser signal (R) against said road surface (16), wherein said second laser signals (S, T, U) comprise both a specularly reflected component and a diffusely reflected component from the road surface (16);
- and
- a control unit (20) comprising a microprocessor programmed to process the parameter (PC) indicative of the superficial condition of said road surface (16), based on an intensities of said second laser signals (S, T, U), said intensities being determined by a number of photons detected, in use, by said plurality of SPADs (11a, 11b, 11c);
- said parameter being indicative of the superficial condition selected from a group consisting of a dry, a partially wet, a completely wet, or an icy road surface (16);
- wherein said sensor (10) further comprises:
- a plurality of polariser filters (25a, 25b) configured to be hit by selected ones of the second laser signals (S, T, U) determined by the reflections of said first laser signal (R) on said road surface (16), each of the reflections are optically aligned with a respective one of the plurality of SPADs (11a, 11b), configured to receive the second laser signals (S, T, U) reflected from the road surface (16);
- wherein said second laser signals (S, T, U) comprise a first component polarised in a first plane (P) and a second component polarised in a second plane (Q);
- and
- wherein the plurality of SPADs (11a, 11b, 11c) comprise a plurality of first SPADs (11a, 11b) arranged in sequence relative to said polariser filters (25a, 25b) and associated with respective polariser filters of said plurality of polarizer filters (25a, 25b), so as to detect said first or second polarised component;
- and
- a second SPAD (11c) not associated with any polariser filter and arranged with an optical axis substantially coincident with a normal (N) direction to said road surface (16), said second SPAD (11c) being configured to detect a third, non-polarised component of said second laser signals (S, T, U) generated, in use, through the diffuse reflection of said first laser signal (R) on said road surface (16);
- wherein said control unit (20) is programmed to process said parameter (PC) indicative of said superficial condition of said road surface (16), based on a first intensity (ITM) of said first component and on a second intensity (ITE) of said second component, wherein said first intensity (ITM) and said second intensity (ITE) are determined by photon-counting measurements performed by a respective one of the plurality of first SPADs (11a, 11b);
- said first plane (P) being, in use, parallel to said road surface (16) and said second plane (Q) being, in use, orthogonal to said road surface (16).
16 more elements
A method to detect a parameter associated with a superficial condition of a road surface (16), comprising:
- detecting the parameter associated with the superficial condition of the road surface (16) with a sensor (10) by;
- i) emitting a first laser signal (R);
- ii) reflecting said first laser signal (R) onto said road surface (16) to generate second laser signals (S, T, U), wherein said second laser signals (S, T, U) comprise both a specularly reflected component and a diffusely reflected component from the road surface (16), and wherein said second laser signals (S, T, U) comprise a first component polarised in a first plane (P), a second component polarised in a second plane (Q), and a third non-polarized component;
- iii) detecting said second laser signals (S, T, U) by means of a plurality of single-photon avalanche diodes (SPADs) (11a, 11b, 11c) configured to detect the second laser signals (S, T, U);
- iv) processing the parameter (SC) associated with the superficial condition of said road surface (16), based on intensities of said second laser signals (S, T, U);
- said intensities being associated with a number of photons detected, in use, by said plurality of SPADs (11a, 11b, 11c), wherein the plurality of SPADs comprises a plurality of first SPADs (11a, 11b) and a second SPAD (11c),
- wherein the plurality of first SPADs are arranged in sequence relative to polariser filters (25a, 25b) for detecting the first component polarised in the first plane (P) and the second component polarised in the second plane (Q), and
- wherein the second SPAD (11c) is not associated with any polariser filter and is arranged with an optical axis substantially coincident with a normal (N) direction to said road surface (16) for detecting the third non-polarized component;
- said parameter being associated with said superficial condition selected from a group consisting of a dry, a partially wet, a completely wet, or an icy road surface (16);
- v) filtering, by means of a plurality of polariser filters (25a, 25b), said second laser signals (S, T, U) determined by the reflection of said first laser signal (R) on said road surface (16);
- said reflected second laser signals (S, T, U) comprising the first component polarised in a first plane (P), the second component polarised in a second plane (Q), and the third non-polarised component;
- and
- vi) detecting, by means of the plurality of first SPADs (11a, 11b) said first or second polarised component and/or detecting by means of the plurality of second SPAD (11c) the third, non-polarised component;
- and
- vii) processing said parameter associated with said superficial condition of said road surface (16), based on a first intensity (ITM) of said first component and on a second intensity (ITE) of said second component, and/or by an intensity of the third, non-polarised component;
- said first plane (P) being, in use, parallel to said road surface (16), said second plane (Q) being, in use, orthogonal to said road surface (16), and said third non-polarised component being at the normal (N) direction to the road surface (16).
13 more elements
Dependencies are inferred from the claim text.