ES2316307B2 - SAFE DEVICE FOR DRIVING AGAINST SITUATIONS OF DEAD OR SLEEPING MAN. - Google Patents

Abstract

Safe device for driving in front of situations of dead or sleeping man.

The present invention details a device driving insurance in situations of dead man or asleep comprising controls for manual control of vehicles or machines on which a sensor network is distributed piezoelectric and pyroelectric. The information of these sensors It is managed by the control electronics with the help of a model of behavior for evaluation of risk situations. Bliss electronics allows sending command signals to elements that act on the user to alert him or on the vehicle or machine to return to a security situation. It turns out especially useful to avoid intentional deactivation attempts by of the user, which have been the cause of many accidents of railway.

Description

Safe device for driving in front of situations of dead or sleeping man.

Technical sector

The invention falls within the technical sector of Safety in vehicles and machines. More specifically in the concerning interlocking devices and devices "dead man", acting by stopping the vehicle or machine in case of loss of control or fade of the operator.

State of the art

"Man switches or devices dead "have the function of stopping a vehicle or machine in cases in which the operator loses control of it and its Design aims to always be fail safe. Are used commonly in locomotives, forklifts, lawnmowers, tractors and others.

Interest in these systems increased with the appearance of trams and electrified locomotives, since in the steam locomotives there was always an officer next to the driver responsible for controlling the fuel supply to the engine. With the trams, subways and suburban trains later, the driver began to find himself isolated in a passenger compartment nobody could access in case of loss of control by fading, which resulted in numerous accidents that led to the introduction of "dead man" devices.

The conventional devices used in locomotives have control knobs that must be pressed in a manner maintained by the operator during the running of the train. He control knob usually has a mechanical return system spring type that, in case of operator fading, what returns to its resting position, in which a switch that activates the emergency brakes.

Different designs based on this system in which the control knob is a button, a wheel, a lever, a joystick and others, are widely used even though They present a remarkable security problem. Keep up the pressure on a command, overcoming a spring return system, It is annoying for operators who, on numerous occasions, have opted to place some kind of mechanical lock (weight, rope or similar) to hold the control in the running position and avoid having to exert the required pressure on their own. In such a situation, sleep, dizziness, fainting or any serious problem that affects the driver, carries hopelessly to a situation of extreme danger, which in many Sometimes it has ended in fatal accidents.

Other dead man systems have searched also fail-safe designs, such as the use of:

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Pedals replacing controls manuals, but which can also be uncomfortable for the operator and induce him to place a weight on the pedal for reasons of muscle overload, which leads to problems similar to exposed above.

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Contact sensors that allow to detect if the operator's hand exerts contact on the command, but that do not allow to evaluate possible situations in which the driver falls asleep, being sensors that do not differentiate pressures

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Optical sensors that also allow to detect if the operator's hand exerts contact, but that They are also easy to sabotage by placing an adhesive tape opaque over the sensor.

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Seat switches, generally used in tractors, intended to cut the engine If the driver gets off or falls off the tractor. In case of fading, however, the tractor would continue to run and It could cause an accident.

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Optical sensors that allow evaluate the driver's blink frequency and activate some type of alarm signal in case of noticeable change in said frequency (usually decrease in frequency), which occurs In sleep situations.

Among the patents found related to These systems highlight:

WO0018012 " Dead-man switch " .- It is about a control for vehicles that by pressure effect is able to detect situations of driver fading and send a signal to disconnect the engine transmission.

US2006164254, DE10332823 and WO03093048.- Describe capacitive sensors embedded in handles or seats for detect the operator of the machine or vehicle by means of the pressure it exerts.

KR20040041479 " Device for detecting seating in vehicle for outputting signals in taking seat or getting up from seat " .- It is about a seat switch in which the cushion has a spring intended for closing the switch only when the driver is sitting on the seat .

US2006151227 " Automobile with vehicle seats equipped with pressure sensors " .- Contains sensors included in the seats of a car to assess the pressure exerted on different parts of the seat and act through a control unit to increase user comfort.

WO9805543 " Steering wheel with opto-electronic sensor " .- It has a steering wheel with fiber optic included inside, through which light is passed continuously. Changes in pressure on the steering wheel cause changes in the transmission of light through the optical fiber, which, when properly evaluated, allow the programming of actions.

The publication " Monitoring eye and eyelid movements by infrared reflectance oculography to measure drowsiness in drivers " describes a dead man system that uses infrared oculography to detect fatigue in drivers. The performance of tests in a driving simulator is explained, in which the movement of the eyelids of the different participants is evaluated.

Commercial products such as the " Angel driver nzapper " propose to detect the patient's sleep based on the inclination and movements of his spine. It is placed in the ear and detects any movement or inclination of the head that incites sleep or fatigue, alerting the driver by high frequency beeps of his
state.

In many of the systems discussed, the problem is that the sensor allows to evaluate a single magnitude physics, usually pressure, so the system does not work User-proof cheat insurance. Would result It is convenient to have a sensor network that would allow evaluation simultaneously two magnitudes and decide the actions in function of a cross comparison of these magnitudes. It would arrive like this to a more reliable system, both in cases of failure to detect one of the magnitudes, as in cases of attempted sabotage of the system.

There are certain polymers that have both piezoelectric properties (electromechanical coupling) as pyroelectric (thermomechanical coupling). Respond front to changes in pressure and / or temperature generating a difference of potential between its extremes, which makes them possible candidates for be part of a sensor network that would allow evaluation simultaneously pressure and temperature, as previously proposed for solve problems in dead man systems explained.

In the past these polymers have been used in the development of pressure sensors as described in US2004181117, JP2005201044 and US5760530. In these systems, the presence of an additional thermoelectric coupling (the pyroelectric effect) was always an annoying source of noise that distorted the pressure signal. In fact there are patents such as US2006152375 " Pressure-sensitive sensor and object detector " that set out procedures to compensate for pyroelectric effects and only consider pressure effects.

In other cases these polymers have been used in the development of temperature sensors or detectors infrared, as described in US2007187605 and in US2007108385, being in these cases the electromechanical coupling the possible causing unexpected signals in these systems.

What in these systems was a problem, if combined with a microcontroller that has a suitable piezoelectric-pyroelectric behavior model, can be decisive in obtaining a dead man device that allows simultaneous evaluation of the evolution of two magnitudes (pressure and temper-
tura).

It is described with this invention how to arrive at a dead man device based on the advantages provided by piezoelectric and / or pyroelectric polymers as sensors.

With the intention of achieving dead man systems that are "essentially safe" and that are both comfortable for operators, in order to solve some of the above problems, the invention is proposed " Safe device for driving in situations of dead man or asleep "described in detail below.

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Detailed description of the invention

The present invention details a device driving insurance in situations of dead man or asleep comprising controls for manual control of vehicles or machines on which a sensor network is distributed piezoelectric and pyroelectric. The information of these sensors It is managed by the control electronics, to which the network of sensors is connected, with the help of a behavior model for evaluation of risk situations. This electronics allows sending command signals to elements that act on the user to alert you to the vehicle or machine to resume A security situation. It is especially useful to avoid intentional deactivation attempts by the user, which They have been the cause of many work and rail accidents. The different components that make up are detailed in this section. The invention and its fundamental characteristics.

The safe device for driving in front of situations of dead or sleeping man includes:

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One or more controls for control manual of a vehicle or machine that has a network or matrix of piezoelectric and / or pyroelectric sensors distributed over the area susceptible to contact with the operator's hands and connected to control electronics. Said array of distributed sensors throughout the contact area, along with the behavior model for risk detection and evaluation, it allows to know the situation of each part of the operator's hands in contact with The control knob. Below a contact threshold determined, the processor manages alerts about the operator and the actions on the vehicle or machine, to return to the security situation.

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A control electronics, with at least battery, processor, communications module and antenna, with functions of:

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\ vtcortauna Conditioning, treatment and analog-digital (A / D) conversion of the signal from the different sensors.

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\ vtcortauna Treatment of the information coming from the sensors, on the evolution of pressures and / or temperatures, based on a model of combined piezoelectric-pyroelectric behavior adjusted for the detection and evaluation of risk situations.

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\ vtcortauna Management of actions, based on the results of the information processing, by sending command signals to the actuators (whose function is to notify the operator).

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\ vtcortauna Management of actions, based on the results of the information processing, by sending signals to remote devices (whose function is to act on the vehicle or machine).

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\ vtcortauna Receipt of additional command signals from remote control centers as a complement to the behavior and risk assessment model.

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One or more actuator elements with possibilities of acoustic, vibratory, luminous or combination thereof or any other type, with control about its intensities and durations intended to alert the operator.

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One or more remote devices with possibilities of mechanical, electrical, pneumatic actuation, Hydraulic, chemical or combination thereof or any other type, intended to bring the vehicle or machine to a situation safe.

Explained the elements that comprise the invention, information relating to details of these elements or possible materializations of the same.

Piezoelectric and / or pyroelectric sensors, which constitute the network or array of sensors, are sheets polymeric whose reduced thickness (usually from 20 to 200 micrometers) and high flexibility facilitates placement, as well as its distribution over the entire area susceptible to contact with Operator's hands Being the whole sheet that presents the degree of necessary crystallinity that gives the polymer its piezoelectric and / or pyroelectric properties, any geometry trimmed from a sheet of said material, to adapt under control, it also presents the necessary properties for detection tasks. The reduced thickness facilitates its integration in the control command and allows the use of additional protective coatings, without reaching sensors bulky, which also simplifies assembly tasks and allows to optimize the final ergonomics of the control knob.

As polymers with piezoelectric properties and Pyroelectric can be used, among others, the polyfluoride of vinylidene or PVDF - (CH2-CF2) - „and its copolymers, such as poly (vinylidene-trifluoro fluoride ethylene) or P (VDF-TrFE).

The combined behavior model piezoelectric-pyroelectric for detection of Risk situations include the following parameters:

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Thickness of the sensors that they constitute the network or array of sensors.

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 Effective area of sensors

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 Modulus of elasticity of sensor material.

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 Dielectric constant of sensors

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 Piezoelectric coefficients of the sensor material.

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 Pyroelectric coefficients of sensor material.

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 Electric resistance equivalent of the sensors.

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 Equivalent capacity of sensors

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 Thermal conductivity of sensor material.

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 Specific heat of the material of the sensors.

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 Material density of sensors

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 Material thickness for sensor coating.

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 Modulus of elasticity of material for coating the sensors.

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 Thermal conductivity of material for coating the sensors.

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 Specific heat of the material for the coating of the sensors.

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 Material density for the sensor coating.

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 Equivalent resistance of conditioning circuit

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 Equivalent capacity of conditioning circuit

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 Amplification factor electronics.

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 Transmission coefficients of convection heat around the control knobs (zone exposed to the environment).

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 Transmission coefficients of heat by conduction around the control knobs (zone in contact with other solid parts of the device).

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 Thermal resistance of contact for heat transmission between the operator's hands and Control knobs

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 Other adjustment factors for The concrete application.

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In the case of various materials for sensors or coatings the model includes the properties commented above for each of these materials. They are explained the relationships between the different parameters below.

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For the detection of pressure changes of Contact:

Figure 2 shows the sensor scheme piezoelectric. The displacement of loads produced when applying a force on the piezoelectric sensor can be represented by the equivalent electrical circuit represented in the Figure 3.

The force F on the sensor acts as a intensity generator that fed to a capacitor capacity "C" according to the following equation:

C = C (F) = \ varepsilon \ cdot (L1 \ cdotL2) / e

Being:

? - The dielectric constant of the sensor.

L1 \ cdotL2.- The effective area of the sensor.

e.- The thickness of the sensor.

The thickness of the sensor, "e", depends on the initial thickness, "e0", of the applied pressure, \ sigma = F / (L1 \ cdotL2), and the modulus of elasticity of the material of the sensors, E, through the following expression:

e = e0 \ cdot (1 - \ sigma / E)

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The current intensity, "I", generated with the application of force "F", it depends on the coefficient piezoelectric transverse sensor "d33" according to the equation next.

Q = d33 \ cdot F \ rightarrow I = dQ / dt = d33 \ cdotdF / dt

When the sensor is connected to an external circuit as shown in Figure 3, it is downloaded based on the equivalent "R" resistance of said external circuit. The following differential equation, once integrated, allows to obtain the voltage at the output of the equivalent circuit "U":

I = d33 \ cdotdF / dt = U / R + C \ cdotdU / dt

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For the detection of changes of temperature:

Similar to the effect of changes in pressure, changes in sensor temperature act as a intensity generator that fed to a capacitor capacity "C" according to the following equation:

C = C (F) = \ varepsilon \ cdot (L1 \ cdotL2) / e

The current intensity, "I", generated by the temperature change "\ DeltaT", depends on the pyroelectric coefficient "p3" of the sensor material according to the next equation.

Q = p3 \ cdot (L1 \ cdotL2) \ cdot \ DeltaT \ rightarrow I = dQ / dt = p3 \ cdot (L1 \ cdotL2) \ cdot dT / dt

To evaluate temperature changes in the piezoelectric material - pyroelectric sensors It is necessary to consider the thermal insulation produced by protective coatings. A model of calculation by finite differences that allows to evaluate the evolution of the temperature inside the sensor, resolving so approximate driving equation in non-permanent regime:

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one

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Written this way, each side of the equation represents the amount of heat storage time, by unit of volume, at one point. Being:

k.- The conductivity of the material in the environment Of the point.

T.- The point temperature

- The density of the material in the environment Of the point.

cp.- The specific heat of the material in the point environment.

x, y, z.- The propagation directions of the hot.

\ frac {\ partial} {\ partial} .- The derivative partial of one magnitude with respect to another.

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The approach is then developed by Finite differences. For the pyroelectric sensor it can be split of the one-dimensional case without loss of generality:

2

For resolution, the sensor is divided into different sections with equal or unequal spacing, at each one of which is assigned a node whose temperature is representative of the entire associated section. The number of nodes is choose depending on the accuracy you want to obtain in the solution. For each point "i" of the nodal network applying the explicit formulation to the one-dimensional conduction equation is must comply:

3

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Being:

Ti.- The temperature of node "i" in the instant "t".

dt.- Reduced interval of time to apply the calculation by finite differences to the resolution of the equation differential.

Ti '.- The temperature of node "i" in the instant "t + dt".

Ci.- The thermal capacity of the volume of the cell or section associated with node "i" and defined by Ci = Vi \ cdot \ rho \ cdot cp. With "I saw" the cell volume, "cp" the specific heat of the cell material and "p" The density of the cell material.

qi.- The amount of heat (external or internal added to node "i").

\ sum \ limits_ {j} .- The sum in j that is extends to all nodes "j" adjacent to node "i".

Rij.- The thermal resistance between the node "i" and node "j". Said transmission resistance of heat, depending on the location of the nodes and the environment of the associated cells or sections, will be defined according to the form of heat transmission

For driving transmission.- 4

Xij being the distance between node "i" and node "j", k the thermal conductivity between the nodes and Akij the area of heat exchange by conduction between the cells associated to the nodes.

For convection transmission.- 5

Hij being the convection coefficient between the nodes and Acij the heat exchange area by convection between the cells associated to the nodes.

Considering additional thermal contact resistance (especially in the hand-sensor contact) .-
6

Rtc being the thermal contact resistance between node "i" and node "j" and Akij the area of heat exchange by conduction between the cells associated with the nodes

With the previous equations you have a model of behavior that allows you to quickly study the influence of parameter modifications and optimize the process of device design.

The amplification factor of the amplifier load provides the ratio between load generated by the sensor or piezoelectric sensors - pyroelectric and the voltage generated at The amplifier output. Said voltage is taken as input to a data acquisition card that allows you to represent your evolution with the help of computers, oscilloscopes or other devices for signal analysis.

The adjustment of the model is done once placed the array of sensors in the control and performing tests real, which are compared to simulations until you can define the appropriate values for the adjustment factors. Adjusted the model, you can simulate multiple cases that represent real situations of pressure and temperature variations.

The study of these simulations and their application to real cases allows to know the typical frequencies response to pressure or temperature variation and, for therefore, to be able to study the two effects in an uncoupled manner.

According to the above the behavior model allows to accurately simulate and characterize behavior of the system and its response to pressure changes and simultaneous temperature (output voltage in response to pressure and temperature changes responsible for displacements of loads).

Thanks to the conditioning electronics, Each sensor provides a stable output voltage, whose level varies by variations in pressure and / or temperature. Thanks to have the behavior model as a reference standard and to know the typical response frequencies for variations in each of the magnitudes, you can know the reason that has caused the change in the level of the output voltage.

It is well known if the operator loses contact with the zone controlled by said network sensor. Sabotage intended by placing weights, clamps, jaws or others objects to maintain pressure on the sensor, would be detected thanks to the level change induced by thermal change (by raise your hand stops driving transmission hand-command and it goes into a convection situation air-control).

If this level change situation does not permissible explained happens for a number of network sensors greater than a certain number (adjustable by the processor according to the experience, age, visual acuity and other user variables, vehicle, machine or application), the processor proceeds to send the action orders to actuators and devices remote

Sending information between the electronics of control, actuators and remote devices can be perform through both wired and wireless technologies  (for example Bluetooth, Zig-Bee, radio, infrared or any other technology). One or more can be used signal repeaters to facilitate communication between different elements of the invention.

In cases that require managing a high number of sensors or higher computing power, the electronics of control can be replaced by an acquisition card with sufficient number of channels to receive the information of all the sensors in the network. In this case, the card acquisition would exercise the mission of conditioning, treatment and analog-to-digital (A / D) signal conversion coming from the different sensors. This acquisition card would be connected to a computer, which would handle the tasks of information processing, detection and evaluation of risk situations, management and delivery of orders for performances and the reception of signals from centers remote control

Among the actuator elements intended for alert user is included mobile phone, phonebook electronics or any portable electronic device with telecommunication capabilities Likewise the own controls of control can have internally coupled vibrators that vibrate the control knob to alert the user, when Receive the order of action.

Remote devices can present a own electronics, which receives command orders from the control electronics or remote control centers, and that activates a mechanical, electrical, pneumatic, hydraulic, chemical or combination thereof or any other type. Such performance it materializes in some way from those set forth below or combination thereof, with the purpose of carrying the machine or vehicle to a security situation:

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Activating a brake intended for slow down or stop the vehicle or machine.

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 Releasing the transmission of motor to drive shaft.

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 Cutting engine injection of combustion that drives the vehicle or machine.

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 Cutting the power of the engine that drives the vehicle or machine.

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 Acting on the system of address of the vehicle to direct it to a safe area.

This ensures a greater guarantee of security since that there are actuators to warn of the danger, intended to act on the operator, combined with remote actuator devices to carry the machine or vehicle to a safe situation, and they can act on the system of power, the braking system or the steering system of the machine or vehicle

In turn there is the possibility that the user, once alerted of the danger situation, can stop by means of a button (thus guaranteeing the user's awareness) the subsequent sending of command signals to remote devices and continue with the manual control of the vehicle or machine.

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Brief description of the drawings

Figure 1.- Schematic representation of the main elements of the invention . The different components of the device are shown in the figure:

one.-

Control command.

2.-

Matrix or sensor network.

3.-

Control electronics

4.-

Actuator element to alert the Username.

5.-

Remote device to carry vehicle or machine to a safe situation.

6.-

Possible signal repeater.

7.-

Sensor connections to the control electronics

Figure 2.- Piezoelectric - pyroelectric sensor scheme.

8.-

Force application.

9.-

Sensor Thickness

10.-

Length L1.

eleven.-

L2 length.

Figure 3.- Electrical scheme of the piezoelectric - pyroelectric sensor behavior.

12.-

Voltage generated

13.-

Equivalent circuit resistance to the sensor conditioning circuit.

14.-

Capacitor equivalent to Load storage between sensor electrodes.

fifteen.-

Load generator equivalent to sensor subject to changes in pressure or temperature.

Exposure of at least one embodiment of the invention

The present invention is further illustrated. by the following embodiment, which is not intended to be limiting its scope.

As polymers with piezoelectric properties and Pyroelectric to get the sensors can be used, between others, vinylidene polyfluoride or PVDF - (CH2-CF2) -_ {n} and its copolymers, such as poly (vinylidene-trifluoro fluoride ethylene) or P (VDF-TrFE).

Generally these polymers acquire these properties during mechanical stretching simultaneously to the application of a strong electric field that helps polarize its molecules Therefore not only the chemical composition of said  materials, but also their transformation processes help Enhance its properties. The stretched mechanical gets the step of the phase with random orientation to the so-called beta phase semicrystalline in which the dipoles have partial orientation. The application of high intensity electric field or "process polarization "finishes rotating the dipoles thus obtaining piezoelectric and pyroelectric properties much more Featured

Once the polymer sheet is obtained with piezo and pyroelectric properties and thicknesses generally in the range of 20 to 200 micrometers, it is necessary to metallize their faces to make connections and build the network or matrix of sensors. This is achieved by depositing metals with Au, Pt, Al, Cu, Ag and others through physical deposition technologies of steam (PVD) or chemical vapor deposition (CVD), whose fundamentals They are explained below.

In physical deposition technologies a from steam (PVD), it is based on a solid material that intends to deposit on a substrate. To turn steam into material to deposit, direct heating is performed (in the PVD technologies of evaporation or epitaxy of making molecular) or bombardment with energy ions (in different PVD technologies of "sputtering" and ion beam deposition). Said steam condenses on the substrate surface (in this case the piezo and pyroelectric polymer) thus forming the electrode or desired metal coating.

In chemical deposition technologies a from steam (CVD), it starts directly from gases (sometimes in liquid form that go into vapor state), which by reaction chemistry give a new product that condenses, in the form of a film thin, on the substrate substrate (in this case the polymer piezo and pyroelectric) thus forming the electrode or coating desired metal. Among the different types of CVD technologies, (primarily thermal, plasma assisted and assisted by laser), you have to choose the ones that allow you to deposit at low temperatures not to damage the polymer substrate.

Softening and melting temperatures relatively low polymers, make the temperature working limit for thin layer deposition by processes PVD and CVD are about 180ºC. In the specific case of the PVDF it is Convenient that the working temperature be lower than 120ºC, temperature at which it begins to lose its properties piezoelectric and pyroelectric due to increased mobility of dipoles

In the case of requiring the transfer of a determined pattern on the polymer sheet, and thus get electrodes with more complex shapes and geometries, can be used the technology called photolithography. In this technology the base or substrate material is coated with a thin metallic layer, deposited by PVD or CVD technologies normally. Then you Coated with a layer of photosensitive resin using "spin-coating" or "dip-coating" generally, being subsequently subjected to UV light through a protective mask, with which the resin curing is achieved according to the pattern wanted. A developer is then used to remove the resin from the uncured area, leaving areas with exposed metal and areas with metal protected by resin. It is possible to perform a selective acid attack, which removes metal from the area exposed. Finally the hardened resin layer is removed with other agents, finally leaving the initial substrate with a metallic deposit according to a specific pattern and with details that they reach about 5 micrometers of precision. It can facilitate the connection and integration of the sensor polymer sheets in more complex systems or systems in which electronics have a high degree of miniaturization.

Once the sensor sheets are obtained, they are they can trim, wire, coat with protective layers using polymer sheets with acrylic pressure adhesives to obtain network sensors, whose total thickness may be less than 150 micrometers

Subsequently the sensors are distributed over the control knobs to cover the entire area susceptible to contact with the operator's hands and connect with the control electronics For this, adhesives or introduce into housings designed for this purpose on the surface of the controls, which can finally be covered with a cloth or protective polymer

In interior accommodation at the controls of control or adjacent to them, actuators can be placed vibrators, which are also connected to the control electronics and are activated by it in dangerous situations, to notify the user of the machine or the driver of the vehicle.

The control electronics have a load amplifier, which allows to transform the displacement of charges, produced within the polymer due to pressure effects and temperatures, at an analog voltage output. At the exit of Load amplifier also has a filter to remove signal noises and a digital analog converter. Bliss digital output can be managed by the processor or microcontroller that also has electronics and in which the combined behavior model is included piezoelectric-pyroelectric for evaluation of risk situations. It also includes a communications module with antenna for receiving and sending command signals associated.

The antenna and the communications module that has the control electronics allow to establish links of bidirectional communication between said control electronics and the actuator elements intended to alert the operator. At case of a mobile phone or electronic agenda as actuators, a Once the command signal is received, they can notify the operator by means of acoustic or vibratory signals that return the awareness

The antenna and communications module that has the control electronics also allows to establish bidirectional communication links between said electronics of control and remote devices intended to return to the machine or vehicle to a safety situation.

Such remote devices, usually as part of the power, braking or steering systems vehicles or machines, conventionally have a own electronic that allows to dictate their actions. In case of danger is the electronics associated with the remote device which receive the order of the control electronics of our invention and in turn transmits the order of mechanical, electrical action, pneumatic, hydraulic or chemical.

Claims (12)

1. Safe device for driving against situations of dead or sleeping man comprising:

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one or more controls for control manual of a vehicle or machine that has a network or matrix of piezoelectric and pyroelectric sensors distributed over the area susceptible to contact with the operator's hands and connected to the control electronics;

?

control electronics, with at less battery, processor, communications module and antenna, with functions of:

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information processing from the sensors, on the evolution of pressures and temperatures, based on a combined behavior model piezoelectric-pyroelectric adjusted for precise detection and evaluation of risk situations operating in finite differences according to the model:

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100

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being:

I.- the amperage,

U.- the voltage at equivalent circuit output,

R.- la equivalent resistance of the external circuit,

C.- the capacity of the capacitor equivalent to the sensor,

F.- the force applied,

d33.- the piezoelectric transverse coefficient of the sensor,

dt.- a reduced time interval to apply the difference calculation finite to the resolution of the differential equation,

k.- the conductivity of the material around the point evaluated,

p3.- the pyroelectric coefficient of the sensor material,

L1 \ cdotL2.- the effective sensor area,

\ varepsilon.- the dielectric constant of the sensor,

T.- la temperature of the point studied,

\ rho.- the density of the material around the point,

cp.- the heat specific to the material around the point,

Ti '.- la node temperature "i" at the instant "t",

Ti '.- la node temperature "i" at the instant "t + dt",

Ci.- the thermal capacity of the volume of the cell or section associated with the node "i" and defined by Ci = Vi \ cdot \ rho \ cdot cp. With "I saw" the volume of the cell, "cp" the specific heat of the cell material and "\ rho" the density of the material of the cell,

qi.- the quantity of heat (external or internal added to node "i"),

\ sum \ limits_ {j} .- the sum in j that is extends to all "j" nodes adjacent to the node "i",

Rij.- the thermal resistance between node "i" and node "j", said resistance to heat transmission, depending on the situation of the nodes and the environment of the associated cells or sections, are define according to the form of heat transmission,

x.- the address heat propagation,

\ frac {\ partial} {\ partial} .- The partial derivative of one magnitude with respect to another,

\ sqbullet

performance management by sending command signals to the actuators,

\ sqbullet

performance management by sending signals to remote devices,

\ sqbullet

command signal reception additional from remote control centers such as complement to the behavior and evaluation model of risks

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one or more actuator elements with possibilities acoustic, vibratory, luminous or combination thereof, with control over their intensities and durations, intended to alert the operator;

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one or more remote devices with possibilities of mechanical, electrical, pneumatic actuation, hydraulics or combination thereof, intended to carry the vehicle or machine to a safe situation.

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2. Device according to claim 1, wherein The actuator element is a portable electronic device with telecommunication capabilities 3. Device according to claim 2, wherein between the actuator elements are included coupled vibrators to the control knobs to alert the user to vibration. 4. Device according to claim 3, wherein the remote devices act by activating a brake destined to slow down or stop the vehicle or machine. 5. Device according to claim 3, wherein The remote devices act by cutting the injection of the engine combustion that drives the vehicle or machine. 6. Device according to claim 3, wherein remote devices act by cutting off the motor power that drives the vehicle or machine. 7. Device according to claim 3, wherein the remote devices act on the address system of the vehicle to direct it to a safe area. 8. Device according to claim 3, wherein remote devices act by releasing shaft transmission motor 9. Device according to claim 3, wherein one or more signal repeaters are used to facilitate the communication between the different elements of the invention. 10. Device according to claim 3, in the that the control electronics are integrated by a card acquisition; for reception, conditioning and A / D conversion of the signal from the sensors, connected to a computer that evaluates the risk situations according to the behavior model and manages the performances. 11. Device according to claim 3, which comprises a button to activate the change to manual control of the vehicle or machine 12. Device according to claim 1, in the that in sending information between the control electronics, the actuators and remote devices is done by means of wireless technologies