WO2015015236A1

WO2015015236A1 - Safety device for driving in foggy weather

Info

Publication number: WO2015015236A1
Application number: PCT/IB2013/001673
Authority: WO
Inventors: Thomas Berger
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-07-29
Filing date: 2013-07-29
Publication date: 2015-02-05
Anticipated expiration: 2016-01-29

Abstract

Limited vision demands careful and slow driving. To enforce this, a device is proposed that automatically limits the vehicle's speed according to visual conditions, in a most simple way by limiting the engine speed when the fog tail lamp is switched on and more sophisticated devices with sensing fog by LIDAR or with pulsed light source and triggered sensor.

Description

SAFETY DEVICE FOR DRIVING IN FOGGY WEATHER

FIELD OF THE INVENTION

The invention relates to safe driving and security measures therefore, and in particular for avoiding accidents in foggy weather.

BACKGROUND OF THE INVENTION

There are - surprisingly - not as many traffic accidents as could be in foggy weather, albeit most cars do not reduce speed adequately.

However, if it comes to accidents on highways under these conditions, it mostly results in a massive pileup with sometimes dozens of dead and heavily injured persons, long-term blockage and high damage.

Therefore it would be mandatory to enforce adequate speed at foggy weather. However, hitherto this would be difficult to control, since weather conditions may change quickly and particularly fog banks might de dislocated with any little breeze. So regulation can only be made at the point of driving - and more particularly on every car or truck itself.

PRIOR ART

A few attempts had been made to detect fog and raindrops on windscreens, as with US 2.013.0039.544 and EP 2542451 Al , but without consequent intervention on the driving speed - what could have been problematic anyhow, due to the fact, that these systems just monitor the windshield, but not the way ahead.

There had been as well propositions to evaluate driver's behavior and make speed reporting in relation to weather conditions, as taught in US 8.248.223. These however could only evaluate driving in relation to general weather conditions and do not refer to individual visual conditions, furthermore it refers to a post-facto-analysis and gives no chance to intervene.

DESCRIPTION OF THE INVENTION

There are three optional embodiments to this invention: a very simple one, that is based on general correct driver's behavior and two fully automatic, but technically more or highly sophistic ones: The basic inventive step is to restrict the vehicle's speed by limiting the engine speed to an adequate level, as known in cars for generally confining the maximum drive speed.

The simple embodiment refers to switching a fixed limit on and off together with the fog tail lamp. This will help with reasonable drivers, who keep in mind that driving in fog without the tailgate lamp on would not only be an offense, but could lead to fatal liability on subsequent damages. Thus, switching off the tailgate lamp for unlimited speed or not switching it on in fog would mark a considerable risk.

However, for making the system insuperable, modern technologies as LIDAR- sy stems can be applied, which measure density, speed and direction of dust particles and water droplets or snow at given distance ahead, as to be found with Siemens ACC system (at its time a little futuristic - see http://www.springerpro- fessional.de/acc-erkennt-nebel-regen-und-schnee-5345/3940480.html - dated 06.04.2006) and already applied in military aircraft security systems. These constantly approach the cost limits for private application and would be in reach with mass application.

In a more simplified embodiment it is possible to apply a light sensor next to a pulsed light source and to simultaneously measure the alteration its input in relation to the pulse, for to detect the scattering of the light pulses - (which may be of invisible IR) due to fog and rain - disregard the surrounding light sources - and to operate the speed limiting system thereon. These are e.g. published by Jenoptik Co at http://forum.polymermat.de/dokumente/vortraege210307/sen- sorikheckleuchtenJenoptik_hr_apitz.pdf , however not yet in Patent databases.

DETAILED DESCRIPTION ALONG TO THE DRAWINGS

Fig. 1 shows how the vehicle 1 approaches a fog bank 2. The vehicle electronics 3 triggers a control signal 4, which activates the light sensor 5, the beam of which is recorded by detector 6 and is transferred by the evaluation unit 7 to the control module 8, which addresses the limiter unit in the engine management 9 while taking into account data of the vehicle electronics 3 and effects a reduction of the vehicle speed by limiting the engine speed.

Fig. 2 represents a fog, drizzle and dust detection system, comprising a IR- source 10, pulsed by a sequencer 11 , the pulses detected by a IR Sensor 12 and evaluated in a comparator 13, which transfers the signal to put the tailgate light 14 and/or the speed limiting device 15 on.

Claims

What is claimed is

1. A safety device for driving in foggy weather, comprising a limiting unit for engine speed in cars, controlled by a fog tailgate lamp switch or fog sensors.

2. Safety device as to claim 1 , wherein the fog sensing unit is of a LIDAR-type.

3. Safety device as to claim 1 , wherein the fog sensing unit consists of a pulsed light emitting diode, a compatible sensor and an evaluating unit.

4. Safety device as to claim 3, wherein the fog sensing unit comprises infrared LEDs and -sensors.