JP2009061856A - Vehicle performing improved driving control to traffic light waiting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform improved driving control to traffic light waiting so as not to impair quickness of starting after the traffic light waiting while maximally contributing to air quality conservation and economy of natural resources in consideration that the quickness is required in the starting after the traffic light waiting because a traffic light waiting time is comparatively long in an urban crossing. <P>SOLUTION: When the vehicle performs driving force reduction control during the traffic light waiting in the crossing, at least a part of the driving force reduction control is released based on prediction of the traffic light waiting time to provide against the quick starting when a traffic light turns green. The prediction of the traffic light waiting time is performed based on the traffic light of a crossing lane or actual measurement during the traffic light waiting, or may be set to zero at the head of a traffic light-waiting vehicle line. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to drive control related to temporary stopping and subsequent start of a vehicle such as an automobile, and more particularly, driving force for eliminating or reducing driving force on wheels when the vehicle is braked and stopped. The present invention relates to improving drive control of a vehicle including a drive control device capable of performing reduction control.

  In recent years, especially from the viewpoint of saving natural resources and maintaining the atmosphere, when the vehicle is temporarily stopped due to traffic lights or traffic jams, the engine is temporarily stopped or the middle of the wheel drive system is shut off to reduce the driving force for the wheels. It has been proposed and implemented to perform driving force reduction control that reduces the driving force on the wheels to the extent that they disappear or leave a slight creep torque on the wheels. When the vehicle is temporarily stopped due to traffic lights or traffic jams, it is desirable that the vehicle start immediately as soon as the forced stop is resolved.When the driving force reduction control is performed when the vehicle is temporarily stopped When the vehicle restarts, it is necessary to quickly release the driving force reduction control. When the release of the driving force reduction control is delayed when the vehicle starts, the starting performance of the vehicle deteriorates. However, if the driving force reduction control is released too quickly, the driving force will rise more rapidly than if the accelerator pedal is depressed, and the vehicle will not only feel popping out. There is a risk that a shocking noise will occur due to the play.

In response to such problems, the engine is stopped when the vehicle is temporarily stopped and the engine is restarted when the vehicle restarts, while suppressing the feeling of the vehicle jumping out and preventing the vehicle from moving backward. In order to ensure good startability, the following Patent Document 1 proposes to reduce the braking force in accordance with the recovery state of the driving force.
JP 2000-313253 A

Moreover, in order not to generate an impact sound when packing backlash in the wheel drive system, it is necessary to moderate the initial increase speed in starting up the driving torque, but this increases the time required for backlashing, To cope with this, the agile startability after the temporary stop of the vehicle is reduced, and a concept means of “start prediction detection means” that predicts the start of the vehicle during the temporary stop of the vehicle is provided, whereby the vehicle is temporarily stopped. The applicant has decided to start releasing the driving force reduction control at the time when the starting of the vehicle is expected to start, and to increase the agility of the vehicle start even if the loosening speed of the initial start-up of the driving torque is moderated. Was proposed in Patent Document 2 below.
Japanese Patent Application No. 2007-177836 specification and drawings

  Waiting for traffic lights at intersections can take a considerable amount of time. Therefore, if the driving force reduction control is sufficiently performed during a temporary stop while waiting for a signal, it will greatly contribute to the conservation of natural resources and air conservation. However, when the signal turns blue, the start must be agile, and driving force reduction control is performed while waiting for the signal. Come on.

  The present invention addresses the above-mentioned problems associated with applying driving force reduction control to signal waiting, making maximum contribution to natural resource conservation and air conservation, while agility to start after the signal turns blue. An object of the present invention is to provide a vehicle that performs improved drive control for signal waiting so as not to impair the performance.

  In order to solve the above problems, the present invention provides a vehicle including a drive control device capable of performing drive force reduction control that eliminates or reduces the drive force applied to the wheels when the vehicle is braked and stopped. When the driving force reduction control is performed while waiting for a signal, at least a part of the driving force reduction control is canceled based on the prediction of the waiting time until the signal turns blue. It proposes a vehicle that is characterized by being.

  The prediction of the waiting time until the signal turns blue may be performed based on the actual measurement of the signal switching time while waiting for the signal or the fact that the signal of the crossing lane turns yellow.

  The cancellation of at least a part of the driving force reduction control based on the prediction of the waiting time until the signal turns blue may be performed on condition that there is no preceding vehicle in the signal waiting queue. . When at least a part of the driving force reduction control is canceled on condition that there is no preceding vehicle in the signal queue, the waiting time until the signal turns blue is predicted to be 0. Also good.

  Release of at least a portion of the driving force reduction control may include increasing the driving force until the backlash in the vehicle drive system is reduced, and after the backlash is reduced, the vehicle start is braked. The driving force may be further increased to a predetermined limit of the driving force suppressed by. Further increase of the driving force up to the predetermined limit after the looseness may be performed by confirming that the driver is ready to step on the accelerator pedal.

  The vehicle is provided with a braking force holding control device (brake hold control, BH control for short) that holds the braking force on the wheel even after the driver releases the vehicle braking operation. The braking may be based on the braking force holding control of the holding control device.

  As described above, while waiting for a signal in a vehicle equipped with a drive control device that can perform drive force reduction control that eliminates or reduces the drive force on the wheels when the vehicle is braked and stopped. When performing the driving force reduction control, if at least part of the driving force reduction control is to be canceled based on the prediction of the waiting time until the signal turns blue, the driving force reduction control Even if the speed of release, especially its initial backlash, is performed at any moderately moderate speed, it is terminated when the signal turns blue, and the driving force reduction control is maximized while waiting for the signal. In addition, when the signal turns blue, it is possible to start the vehicle with agility without causing a sense of popping out or a rattling impact sound.

  It is unusual to wait for one or more signal changes to pass through an intersection at an intersection in an urban area where the running density of the vehicle is high, the driving force reduction control is activated during signal waiting, and the effectiveness is high. Absent. Therefore, if the waiting time until the signal turns blue is predicted based on actual measurement of the signal switching time while waiting for the signal, the signal switching interval at any intersection and according to changes in time zone and traffic volume Even if is changed, it is possible to accurately predict the waiting time until the signal turns blue according to the situation. Also, according to currently available digital photography technology, it is possible to identify the color of the signal and obtain an electric signal indicating it, so the waiting time until the signal turns blue is predicted to be yellow If it is performed based on the above, it is possible to accurately grasp the time point when the partial release of the driving force reduction control is started in preparation for the start.

  It is important that the start of the first train in the train is made promptly in order to smooth the flow of the vehicle after the signal turns blue, but the vehicles in the second and subsequent queues in the wait queue are The distance between the vehicles must be widened at the start, and the agility at the start is not so important, so at least one of the driving force reduction controls based on the prediction of the waiting time until the above signal turns blue. If the vehicle is released on the condition that there is no preceding vehicle in the waiting queue for the signal, the driving force reduction control based on the prediction of the waiting time until the signal turns blue is automatically released. This is only done when the car is at the head of the signal queue and waiting for the signal, and the driving force reduction control during the temporary stop is fully activated in the second and subsequent vehicles to save fuel. The effect of exhaust gas suppression can be maximizedAccording to currently available radar and infrared forward object detection means, it is possible to detect whether or not there is a preceding vehicle in the signal queue.

  By the way, the vehicle of the present invention cancels at least a part of the driving force reduction control based on the prediction of the waiting time until the signal turns blue, but it is performed on condition that there is no preceding vehicle in the signal waiting queue. This means that when the vehicle is in the middle of the signal queue, the driving force reduction control according to the present invention is not canceled anyway, and the vehicle has come to the head of the signal queue. In other words, the cancellation of the driving force reduction control based on the prediction of the waiting time until the signal turns blue is lifted. It is the final phase of signal waiting that the vehicle comes to the head of the signal queue, and the estimated waiting time until the signal turns blue at this stage may be 0 as its minimum value, that is, this stage Then, the cancellation of the driving force reduction control may be started immediately. At this stage, the waiting time until the signal turns blue is at most one signal switching time.

  If the release of at least a part of the driving force reduction control includes increasing the driving force until the backlash in the vehicle driving system is reduced, the vehicle is about to start, but not yet In the waiting time of the final phase of waiting for a signal, loose play in the vehicle drive system can be loosened. Further, at least part of the cancellation of the driving force reduction control may include further increasing the driving force to a predetermined limit of the driving force so that the start of the vehicle is suppressed by the braking after the backlash is reduced. For example, as will be understood from FIG. 2 described later, since the driving force is raised in advance, even if the braking force is released gradually by the BH control, it is large immediately after the start without being affected by the braking force. Driving energy can be obtained, and the vehicle can start quickly after waiting for a signal.

  If the driver further confirms that the driver is ready to step on the accelerator pedal after the backlash, the driver can quickly increase the driving force after waiting for a signal. The driving force reduction control based on the prediction of the signal waiting time can be executed only when it is desired to start.

  A braking force holding control device for holding the braking force on the wheel even after the vehicle has released the vehicle braking operation by the driver, and the braking force holding control device for braking the wheel while the vehicle is temporarily stopped ( In the case of braking by (BH control), the vehicle can be kept under appropriate braking in preparation for starting even if the driving force reduction control is partially canceled while waiting for a signal according to the present invention.

  FIG. 1 is a plan view showing an example of a state where a vehicle is waiting for a signal at an intersection. Of these, it is assumed that the vehicles A and B now have the signal waiting drive control function according to the present invention. Vehicles A and B are each provided with preceding vehicle detection means such as a radar or an infrared detector for detecting when the own vehicle is in the signal queue and there is a preceding vehicle. In addition, when the vehicle of the present invention predicts the waiting time until the signal turns blue based on the fact that the signal of the intersection lane turns yellow, when the vehicle arrives at the position of the signal waiting stop line at the intersection, Crossing lane signal detection means such as a digital camera capable of detecting the traffic signal S in the lane and detecting that its display changes from blue to yellow is provided. Vehicle A is at the head of the signal waiting queue, and the traffic signal S in the intersection lane is detected by the intersection lane signal detection means, but it is not detected because there is no preceding vehicle in the signal waiting queue. On the other hand, in the vehicle B, the preceding vehicle in the signal waiting queue is detected, but the signal of the intersection lane is not detected. The cross lane signal detecting means is used in one embodiment of the present invention, and the cross lane signal detecting means is not necessary in other embodiments of the present invention.

  FIG. 2 is a graph showing how the braking force and the driving force change with time when the vehicle waits for a signal and starts in the vehicle of the present invention, as compared with the prior art. The upper half of the graph shows the present invention. In the graph, the braking force and the driving force are shown as a braking torque and a driving torque, respectively. In these graphs, at time t0, the vehicle is temporarily stopped after the preceding vehicle that is waiting for a signal on the same lane as its own vehicle, such as vehicle B in FIG. It is the time. If the driver continues to depress the brake pedal even after a temporary stop, the braking torque is maintained as it is as the braking torque by depressing the brake pedal. However, if the driver releases the brake pedal, the braking force retention control is performed. (BH control) is activated, and the braking torque is replaced by the BH torque.

  When the vehicle is stopped and braked for a predetermined time and reaches a time point t1, the driving force reduction control is activated. In this example, the driving torque is reduced to zero. When the signal queue is long and the vehicle is at the position of the vehicle B in FIG. 1 or at a position further rearward of the vehicle, and temporarily stops and slows down, the brake is released, driven, and braked each time. The driving force reduction cycle is repeated. In FIG. 2, it is assumed that after a temporary stop at time t 0, the vehicle starts at time t 2 after one temporary stop. Driving power reduction control from time t1 saves fuel and reduces exhaust emissions. According to the present invention, when the own vehicle comes to the head of the signal waiting queue like the vehicle A in FIG. 1, the drive control according to the present invention is started at the time ta prior to the time t2.

  In the drive control according to the present invention, when the own vehicle is at the intersection entrance as in the vehicle A in FIG. 1 and is in a temporary stop waiting for a signal, the driving force is first driven at the time ta when the estimated waiting time for the signal is cut. It starts with a gentle rise that does not cause an impact until the system is loose. At the time tb, when the play of the driving system is finished, the driving force is increased to a predetermined maximum value (creep torque) within a range where the starting of the vehicle can be suppressed by braking at an arbitrarily set rate. The When this state is achieved at time tc, the driving force is maintained in this state until the accelerator pedal is next depressed. Thus, while the vehicle is waiting in the second and subsequent queues of the signal waiting queue, the driving force reduction control is activated whenever the braking stop time exceeds a predetermined set time, and the driving force is reduced when the accelerator pedal is depressed. The reduction control is released, but when the vehicle is at the head of the signal waiting queue or when the vehicle is alone at the signal waiting position, if the driving force reduction control is activated, it predicts the signal waiting time. And some will be released.

  Next, when the accelerator pedal is depressed at time t2 when the vehicle is at the head of the train (or alone) and the driving force reduction control is partially released and waiting for a signal, braking is applied to the brake pedal. Braking is performed at the brake pedal depressing speed, and when braking is applied by the braking force holding control (BH control), a predetermined reduction set for the braking force holding control is set. The braking force is released at the speed. In the example shown in FIG. 2, it is assumed that the braking force is applied by the braking force holding control, and the braking force is released gently at the releasing speed of the braking force holding control. The vehicle starts at time t3i when the driving force (driving torque) exceeds the braking force (braking torque).

  Compared with the above control, as shown in the lower half of the graph of FIG. 2 as the prior art, when the driving force reduction control is activated by braking the vehicle, it is maintained until the accelerator pedal is depressed. When the accelerator pedal is on, the backlash of the drive system starts from time t2 when the accelerator pedal is depressed. In this case, if the rate of increase in the backlash driving torque is moderately suppressed so as not to cause an impact due to backlash, the start of the vehicle is at time t3c, which is a time that is considerably delayed compared to the above time t3i. In addition, when the vehicle is braked on the way uphill, the BH control is designed to release the braking force so that the vehicle does not move backward by releasing the braking force even if the drive system has a backlash. Therefore, the release of the braking force is set so that the descending line of the braking torque passes through the end point of the backlash torque as shown in the graph. Also in the case of the present invention shown in the upper half of the graph, if braking while waiting for a signal is applied by BH control, the braking torque reduction speed at the time of releasing the brake becomes gentle as shown in FIG. The driving energy obtained until reaching a certain time point t4 after the start is considerably larger than that of the prior art according to the present invention as shown by the hatched portion in the figure, and the agility of the vehicle start after waiting for the signal Will improve.

  FIG. 3 is a block diagram showing the configuration of the control means provided in the vehicle according to the present invention for performing the control described above with reference to FIGS. The control means includes a brake control device that controls the braking force and a drive control device that controls the driving force. This type of control means is substantially the current technology in this field. The computer program is executed by a microcomputer. The braking control device includes a BH control unit that performs braking force holding control as a part of its function. In addition, the drive control device includes a drive force reduction control unit that eliminates or reduces the drive force when the vehicle is braked during operation of the vehicle, and a signal waiting control unit according to the present invention, as a part of its function. It is.

  In the brake control device, a signal indicating the depression state of the brake pedal from the brake pedal sensor, a signal indicating whether or not the driver desires BH control from the BH switch, and a degree of inclination in the longitudinal direction of the vehicle body from the G sensor A signal indicating the vehicle speed is supplied from the signal and the vehicle speed sensor. The drive control device includes a signal indicating an accelerator pedal depression state from an accelerator pedal sensor, a signal indicating that a vehicle is approaching an intersection from a car navigation system, a signal waiting train from a preceding vehicle detection means such as a radar or an infrared detector. When there is a vehicle preceding the vehicle in the vehicle, a signal indicating that there is a vehicle, a signal indicating that the signal of the intersection lane changes from blue to yellow from the intersection lane signal detection means consisting of a digital camera, etc., from the accelerator pedal depression posture sensor A signal indicating whether or not the driver is ready to step on the accelerator pedal is supplied. The accelerator pedal depression posture sensor may be omitted. The braking control device performs braking control of the vehicle based on the signal from each of the above-described sensors while referring to the operation state of the drive control device, and operates the braking device for each wheel via the hydraulic circuit. The drive control device performs vehicle drive control based on signals from the accelerator pedal sensor, the car navigation system, the preceding vehicle detection means, and the cross lane signal detection means while referring to the operation state of the brake control device, and includes an engine, a motor, The drive system apparatus including the machine is operated. In the embodiment shown in FIG. 4 and call 5 below, there is no need to have a cross lane signal detection means.

  FIG. 4 is a flowchart showing a procedure for performing signal waiting drive control of a vehicle according to the procedure shown in FIG. 2 by the control means shown in FIG. 3 according to one embodiment. The control according to the flowchart is repeatedly executed at intervals of several tens of milliseconds while the vehicle is in operation by sewing the interval between other operation controls by the microcomputer constituting the braking control device and the drive control device of FIG. It is good.

  When control is started, it is determined in step (S) 10 whether or not the accelerator pedal is depressed. Since the partial release control of the driving force reduction control according to the present invention is not necessary as long as the accelerator pedal is depressed, when the answer is yes (Y), the control proceeds to step 310 described later, and a post-start process described later is performed. It is. If the answer is no (N), control proceeds to step 20.

  In step 20, it is determined whether or not the flag F1 is 1. The flag F1 is set to 1 when the control reaches step 100 to be described later. Until then, the flag F1 is reset to 0 at the start of the control or at step 340 in the preceding control. Since there is so far, the answer is no and control proceeds to step 30.

  In step 30, it is determined whether or not the vehicle is braking. The vehicle may be braked by depressing the brake pedal by the driver, or by braking force holding control (BH control). When the vehicle is not braking, the control according to the present invention is not performed. Therefore, when the answer is no, the control of this time is finished. If the answer is yes, control proceeds to step 40.

  In step 40, it is determined whether or not the vehicle speed V is equal to or lower than a predetermined vehicle speed Vo. This step is a step of determining whether or not the vehicle is in a temporarily stopped state, where V = 0? However, here, Vo is set to a certain value close to 0, and the state in which the vehicle is slightly creeping is also included in the control target. If the answer is no, the control of this time is finished. If the answer is yes, the control proceeds to step 50.

  In step 50, it is determined whether or not the vehicle is in a position in front of the signal so that it is determined that the stop of the vehicle corresponds to a stop waiting for a signal. This may be determined from information from the car navigation system. If the answer is no, the control of this time is finished. If the answer is yes, the control proceeds to step 60.

  In step 60, it is determined whether or not the flag F2 is 1. The flag F2 is set to 1 when the control reaches step 80 to be described later. Until then, the flag F2 is reset to 0 at the start of the control or at step 340 in the preceding control. So, until then, the answer is no, control proceeds to step 70, and the timer is reset. This timer is reset each time a new condition occurs when the accelerator pedal is not depressed, the vehicle is braking, the vehicle is almost stopped, and the vehicle is in front of the signal. It is a timer that keeps counting the elapsed time. The measured value of this timer is a time used for determining whether or not the start time of partial cancellation of the driving force reduction control performed in step 190 described later has come. When the timer is reset in step 70, the flag F2 is set to 1 in the next step 80, so that the same state continues thereafter, and the control bypasses step 70 every time the control reaches 60. And let the timer continue measuring elapsed time.

  In step 90, it is determined whether or not driving force reduction control for eliminating or reducing the driving force is performed while the vehicle is temporarily stopped. Since the driving force reduction control is started after a certain period of time from the start of the vehicle braking pause, the time when the answer to step 90 turns from NO to YES is somewhat delayed from the time when the timer is reset. . When the answer is no, the control according to the present invention is not required, and thus the control of this time is finished. When the answer is yes, control proceeds to step 100 where the flag F1 described above is set. Therefore, once the control proceeds so far, the control that has proceeded to step 20 from the next time proceeds to step 170 described later.

  However, before that, control proceeds to the next step 110, but only once. The following is a process of actually measuring the signal switching time while repeating the signal waiting stop and slow driving. In step 110, it is determined whether or not the flag F3 is 1. Initially, since the answer is no, the control proceeds to step 120, where the value of time tm, which will be described later, is set to an appropriate initial value to, and a count value C described later is set to 1. Control then proceeds to step 130 where the flag F3 is set to 1. Therefore, after that, even if the accelerator pedal is depressed and the control proceeds to step 310 to be described later, that is the gradual advancement of the signal waiting train, and the vehicle speed V is less than or equal to the value Vs indicating the full start of the vehicle. If the answer to 310 is no and the control returns to step 110 without resetting the flag F3 and the later-described count value C to 0 by bypassing step 330 described later, the answer is yes. Yes, control continues to step 140. In step 140, the count value C is incremented by one.

  Then, the control proceeds to step 150, and a calculation is performed by setting a value obtained by adding ts calculated in step 320 described later to to described in step 120 as ts. The value set to ts in step 320 is the time from the start of the signal stop temporary stop to the start of gradual acceleration of the train, so the value of ts starts from to and every time control reaches step 150. In addition, the actual measurement value ts of the time from the start of the temporary stop waiting for a signal to the start of the gradual advance of the train is increased by one. Next, in step 160, calculation is performed by dividing ts by the count value C to obtain tm. The value tm indicates the signal switching time estimated by measuring the time from the stop to the start when the vehicle is repeatedly stopped and started in the signal waiting queue. However, when the signal waiting queue is long, stopping and starting are repeated one or more times, but when the signal waiting queue is not so long, the vehicle will be at the head of the queue with one signal change. At that time, since the time between the stop and the start cannot be measured, to is set as the initial value of tm, and when the stop and start are repeated twice or more times, the initial value is set. The actual measurement value ts is added to the value to, divided by the count value C indicating the number of times, and averaged to obtain tm.

  As described above, when the control reaches step 100 and the flag F1 is set to 1, the state where the accelerator pedal is not depressed continues thereafter. When the control proceeds to step 20, the control proceeds to step 170. Become.

  In step 170, it is determined whether or not the flag F4 is 1. Since the flag F4 is set to 1 in step 200 to be described later, the answer is no until then, and the control proceeds to step 180.

  In step 180, it is determined by the preceding vehicle detection means whether or not there is a vehicle preceding the host vehicle in the signal waiting queue. When the control reaches step 180, the accelerator pedal is not depressed, the vehicle is braked, the vehicle is almost stopped, and the timer measures the elapsed time from the start of braking stop. This means that driving force reduction control is performed to reduce fuel consumption and exhaust gas emissions. If the answer is yes in this state, it means that the vehicle is in the waiting queue and continues after the preceding vehicle. In this state, it is preferable to continue the driving force reduction control as much as possible under the depression of the brake pedal by the driver or the braking of the vehicle by the BH control. Therefore, if the answer is yes, control returns and continues the same control. If the answer is no, control proceeds to step 190.

  In step 190, it is determined whether or not the measured time t of the timer is shorter than a time Δt shorter than the value of tm described in steps 120 and 160. Δt is an allowable error time with respect to the estimation accuracy of the signal waiting time when the signal waiting time is estimated and the driving force reduction control is canceled. If the answer is yes, there is still time before the signal switches, so control returns and the same control continues. When t is not less than tm−Δt and the answer is no, the control proceeds to step 200 where the flag F4 is set to 1 and the following driving force reduction control is partially canceled. When the control proceeds to step 200 and the flag F4 is set to 1, when the subsequent control reaches step 170, the control bypasses steps 180, 190, and 200 and proceeds to step 210.

  In step 210, it is determined whether or not the flag F5 is 1. The flag F5 is set to 1 when the control reaches step 240 described later, and the answer is no until then. Therefore, until then, control proceeds to step 220.

  In step 220, the driving force is increased for loosening the driving system described with reference to FIG. In the next step 230, it is determined whether or not the pre-raising torque Tp that has been raised due to the backlash has reached a predetermined torque Tpg indicating that the backlash completion has been completed. While the answer to step 230 is yes, the control returns from this and the control for increasing the backlash torque is continued unless the accelerator pedal is depressed. When the backlash is complete and the answer to step 230 turns from yes to no, control proceeds to step 240 where flag F5 is set to 1 and control then proceeds to step 250. Thereafter, the control that has led to step 210 proceeds to step 260.

  In step 260, it is determined whether or not the flag F6 is 1. Since the flag F6 is set to 1 when the control reaches step 290 described later, the control advances from step 260 to step 250 until then.

  In step 250, it is determined whether or not the driver is ready to step on the accelerator pedal. As an example, as shown in FIG. 6, when the driver steps on the accelerator pedal 10, a sensor 12 for detecting the proximity of the heel is provided on the floor surface where the heel of the foot comes, or the pedal portion of the accelerator pedal. This may be done by providing a sensor 14 for detecting the proximity of the sole of the foot. However, this step 260 may be omitted.

  In any case, in the following step 270, pre-driving is performed to increase the driving torque to the creep torque described with reference to FIG. The torque increase gradient in this pre-drive may be set to an appropriate value.

  In the following step 280, it is determined whether or not the pre-raising torque Tp by the pre-drive has increased to the creep torque Tpc. While the answer to step 280 is yes, control is now returned and the pre-lift torque due to pre-drive is increased. When the pre-raising torque due to the pre-drive reaches the creep torque and the answer to step 280 changes from yes to no, the control proceeds to step 290, the flag F6 is set to 1, and then the control proceeds to step 300. The pre-raising torque that has been increased to the torque is maintained.

  This state continues until the accelerator pedal is depressed and the answer to step 10 changes from no to yes. When the accelerator pedal is depressed and the answer to step 10 turns from no to yes, the control proceeds to step 310. There are two types of states where the accelerator pedal is depressed and control is switched from the state going from step 10 to step 20 to the state going to step 310. One of them is a state where the queue for waiting for a signal slowly progresses but has not yet entered the intersection, and the other is a full-scale start that proceeds across the intersection. Therefore, in step 310, it is determined whether or not the vehicle speed V is equal to or higher than a predetermined speed Vs indicating a full start across the intersection. If the answer is no, the control proceeds to step 320, where the elapsed time t of the time measurement started in step 70 is read and set as ts. This ts is used to calculate tm when the start by depressing the accelerator pedal ends in the slow progress of the signal waiting train and the control reaches step 160 again. At this time, the control bypasses step 330 and proceeds to step 340, where the flag F3 and the count value C are not yet reset, the flags F1, F2, and F4 to F6 are reset to prepare for the next temporary stop waiting for the subsequent signal. Is done.

  Here, returning to steps 110 to 160, the explanation will be supplemented. If the start after the temporary stop of the signal is not a full start, the control will go through the steps 10 to 100 when the next temporary stop of the signal waiting is started. Step 110 is reached again. Since the flag F3 is 1 at this time, the control proceeds to step 140. If the subsequent signal stop temporary stop is the second time, the count value C is 2 here. In the following step 150, the sum of the to when the first stop waiting for the signal and the ts measured so far at the time of slow start is divided by 2, and the value is divided by 2 and averaged. It becomes.

  Hereinafter, each time the number of times of slowing down waiting for the signal increases, the value of ts increases by the actual measurement value ts of each time, and is divided by C which increases by 1 each time to obtain the predicted value tm of the signal waiting time. .

  When the vehicle waits for a signal and the control proceeds to step 310 due to a full start, the answer to step 310 is yes. At this time, all the flags and the count value C are reset in step 330 and step 340. The control prepares for the next signal waiting.

  In the embodiment shown in the flow chart of FIG. 4 described above, the vehicle is in the middle of a waiting train for a signal by steps 60 to 80, 110 to 160, 320, and the train is switched according to signal switching. The signal waiting time was predicted by measuring the elapsed time from the stop to the start, but as described in paragraph "0015", when the vehicle came to the head of the signal queue, the remaining signal The waiting time is at most one signal switching time. When driving force reduction control is performed at the time of signal stop temporary stop, the obstacle to the delay in the release is particularly in the first car in the signal wait train, and the second and subsequent vehicles in the train wait for the start. Accordingly, since the distance between the vehicles must be increased, the start is almost a slow start. In view of this, the driving force reduction control is performed while waiting for the signal, and when the driving force reduction control is partially canceled based on the prediction of the signal waiting time, this is the above-described step 180. Therefore, if there is no preceding vehicle in the signal waiting queue, the signal waiting time is predicted as the minimum value 0 at this time, and the vehicle is placed at the head of the signal waiting queue. When it comes, it is also conceivable to start the partial release of the driving force reduction control immediately.

  FIG. 5 is a flow chart similar to FIG. 4 showing another embodiment of the present invention based on such an idea. In FIG. 5, steps corresponding to the steps in FIG. 4 are indicated by the same step numbers as in FIG. In this case, steps 60 to 80, 110 to 160, 190, 310, 320, and 330 are deleted from the flowchart of FIG.

  FIG. 6 is a cross-section for detecting the signal waiting drive control of the vehicle in the manner shown in FIG. 2 by the control means as shown in FIG. It is a flowchart shown about one embodiment in case a lane signal detection means is provided. In FIG. 6, steps corresponding to the steps in FIG. 4 or 5 are indicated by the same step numbers as in FIG.

  Steps 60 to 80 and 110 to 160 in the flowchart of FIG. 4 are also performed when partial cancellation of the driving force reduction control based on the prediction of the signal waiting time is performed based on the intersection lane signal changing from blue to yellow. , 310, 320 and 330 are not necessary. Then, instead of step 190 in FIG. 4, it may be determined in step 191 whether or not the signal of the crossing lane has changed from blue to yellow.

  While the present invention has been described in detail with respect to several embodiments thereof, it will be apparent to those skilled in the art that various modifications can be made to these embodiments within the scope of the present invention. .

The top view which shows the example which the vehicle is waiting for a signal in an intersection. The graph which shows the point of the change of the braking force and the driving force with respect to passage of time when the signal waiting and the start are performed in the vehicle of the present invention in comparison with the prior art. The block diagram which shows the structure of the control means with which the vehicle by this invention is equipped. The flowchart which shows the point which performs the signal waiting drive control of a vehicle in the way as shown in FIG. 2 by the control means as shown in FIG. 3 about one embodiment. The flowchart which shows the point which performs the signal waiting drive control of a vehicle in the way as shown in FIG. 2 by the control means as shown in FIG. 3 about another one Embodiment. The flowchart which shows the point which performs the signal waiting drive control of a vehicle in the way as shown in FIG. 2 by the control means as shown in FIG. 3 about another one Embodiment. Schematic which shows the example of arrangement | positioning of the sensor which judges whether a driver | operator is a posture which can step on an accelerator pedal immediately.

Explanation of symbols

  10 ... accelerator pedal, 12 ... heel sensor, 14 ... sole sensor

Claims (9)

  When the vehicle is braked and stopped, the vehicle is provided with a drive control device capable of performing drive force reduction control that eliminates or reduces the drive force applied to the wheels, and the drive force reduction control is performed while waiting for a signal. A vehicle characterized in that at least a part of the driving force reduction control is canceled based on prediction of a waiting time until the signal turns blue when the vehicle is performing.   The vehicle according to claim 1, wherein the waiting time until the signal turns blue is estimated based on an actual measurement of a signal switching time during signal waiting.   The vehicle according to claim 1, wherein the waiting time until the signal becomes blue is predicted based on the signal of the intersection lane becoming yellow.   Release of at least a part of the driving force reduction control based on the prediction of the waiting time until the signal turns blue is performed on condition that there is no preceding vehicle in the signal waiting queue. The vehicle according to claim 1, 2, or 3.   At least a part of the driving force reduction control is canceled on the condition that there is no preceding vehicle in the signal queue, and the waiting time until the signal turns blue is predicted to be 0. The vehicle according to claim 1.   The vehicle according to any one of claims 1 to 5, wherein the release of at least a part of the driving force reduction control includes increasing the driving force until the backlash in the driving system of the vehicle is reduced.   The release of at least a part of the driving force reduction control includes further increasing the driving force to a predetermined limit of the driving force that is suppressed by braking after the play is filled. The vehicle according to claim 6.   The vehicle according to claim 7, wherein the further increase of the driving force up to the predetermined limit after the looseness is confirmed by confirming that the driver is ready to step on the accelerator pedal.   The vehicle includes a braking force holding control device that holds the braking force on the wheels even after the vehicle braking operation by the driver is released, and the braking of the wheels while the vehicle is stopped is performed by the braking force holding control of the braking force holding control device. The vehicle according to claim 1, wherein the vehicle is a vehicle.

Images