JPH01248065A - Device for calculating accelerating and decelerating speed - Google Patents

Abstract

PURPOSE:To improve response of calculation at a low speed range and calculation accuracy at a high speed range by a method wherein a change rate calculated from frequency of pulse signals is specified as accelerating and decelerating speed at the low speed range and the change rate from the number of pulses is specified as accelerating and decelerating speed at the high speed range. CONSTITUTION:A first arithmetic unit of accelerating and decelerating speed calculates speed from frequency of pulse signals having frequency according to speed of a moving object to calculate accelerating and decelerating speed based on its change rate. On the other hand, a second arithmetic unit of accelerating and decelerating speed calculates speed from the number of pulses contained in the pulse signal within specified time to calculate accelerating and decelerating speed based on its change rate. A switching unit uses the calculated value of the first unit at a low speed range and the calculated value of the second unit at a high speed range so as to specify accelerating and decelerating speed of a moving object. This enables calculation of accelerating and decelerating speed over an entire speed range of the moving object without delay in response and deterioration in accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for calculating acceleration/deceleration of a moving object such as a vehicle.

(Prior art) To determine the speed of a moving object when calculating acceleration/deceleration, the speed of the moving object is usually determined by photoelectric detection or the like to detect the passage of the teeth of a pulse gear that rotates together with a rotating member that controls the movement of the object. Usually, a pulse signal of a corresponding frequency is generated, and the speed of the moving object is determined from the number of pulses of this pulse signal during a certain period of time. Then, the acceleration/deceleration of the moving object is calculated by dividing the difference between the speed thus calculated and the previous speed similarly calculated by the speed calculation interval.

(Problem to be Solved by the Invention) However, in the lever method, it is necessary to make the speed calculation interval longer than the maximum period of the pulse signal, and the pulse signal is pulsed at a low speed such as when the speed of the moving object is 20 km/h or less. When the signal period becomes long (using a normal pulse gear and the speed is 20 kin/h, the pulse period is 150 II
Assuming that the speed is about 150 msec), it is necessary to set the calculation interval of the speed, and thus the acceleration/deceleration, to 150 m5ec or more. This means that the responsiveness of acceleration/deceleration calculations deteriorates, and a response delay in the control system that uses acceleration/deceleration as a factor is unavoidable.

To solve this problem, find the speed of the moving object from the length of each pulse signal period, and divide the difference between the speed found in this way and the previous speed found in the same way by the pulse period. One possibility is to calculate the acceleration/deceleration of a moving object.

However, with this method, the calculation interval for velocity, and thus acceleration/deceleration, does not exceed the pulse period, so the above problem does not occur.However, conversely, when the moving object speed is high and the pulse signal period becomes short, acceleration/deceleration calculation is performed. It cannot be denied that the accuracy deteriorates.

(Means for Solving the Problems) The present invention proposes an acceleration/deceleration calculation device that uses both of the above equations depending on the speed of a moving object to avoid the above-mentioned problems. As shown in the following, in a device for calculating the acceleration/deceleration of a moving object from a pulse signal of a frequency corresponding to the speed of the moving object whose acceleration/deceleration is to be determined, the rate of change in speed determined from the period of the pulse signal is calculated as the acceleration/deceleration. a first acceleration/deceleration calculation means that calculates acceleration/deceleration as an acceleration/deceleration rate determined from the number of pulses of the pulse signal during a predetermined period of time; is characterized by a switching means that uses the calculated value from the first acceleration/deceleration calculating means and the calculated value from the second acceleration/deceleration calculating means while the speed of the moving object is high.

(Function) The first acceleration/deceleration calculation means calculates the speed of the moving object from the period in the pulse signal of the frequency corresponding to the speed of the moving object,
Acceleration/deceleration is calculated from the rate of change. On the other hand, the second acceleration/deceleration calculation means calculates the speed of the moving object from the number of pulses of the pulse signal during a predetermined period of time, and calculates the acceleration/deceleration from the rate of change.

The switching means uses the calculated value from the first acceleration/deceleration calculating means when the speed of the moving object is low, and uses the calculated value from the second acceleration/deceleration calculating means when the speed of the moving object is high.
The calculated value from the acceleration/deceleration calculation means is used as the acceleration/deceleration of the moving object.

Therefore, in the low speed range of the moving object where the period of the pulse signal is long, the calculation interval of acceleration/deceleration does not exceed the period of the pulse signal, and it is possible to prevent the responsiveness of calculation from becoming poor. Furthermore, even if the period of the pulse signal becomes short in the high speed range of a moving object where the period of the pulse signal becomes short, the calculation interval of acceleration/deceleration is kept at the predetermined time mentioned above regardless of this short period, and the acceleration/deceleration is This can prevent calculation accuracy from deteriorating. Therefore, the acceleration/deceleration of the moving object can be calculated over the entire speed range without causing a response delay or a decrease in accuracy.

(Example) Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows an embodiment of the device of the present invention. In this example, the microcomputer 1 controls the acceleration/deceleration G of a moving object (not shown).
Configure to calculate. This microcomputer
As is well known, it consists of a (central processing unit) (CPU) 2, a random access memory (RAM) 3, a read-only memory (ROM) 4, an input control circuit 5, an output control circuit 6, and a speed sensor 7. It is assumed that the signal (2) from the input control circuit 5 is inputted to the input control circuit 5, the acceleration/deceleration G is calculated, and the calculation result is outputted from the output control circuit 6.

The speed sensor 7 includes a pulse gear that rotates together with the rotating member that controls the movement of the moving object, and photoelectrically detects the passage of teeth of the pulse gear while the object is moving, and detects a frequency corresponding to the speed of the moving object, for example, as shown in FIG. 3. Pulse signal (speed signal)
■ shall be output.

The CPU 2 receives this pulse signal ■ via the circuit 5,
Based on this input information, the control programs shown in FIGS. 4 to 6 are executed to calculate the acceleration/deceleration G of the moving object, and during this calculation, necessary information is read from the ROM 4, and process information is written to and read from the RAM 3. .

FIG. 4 shows a main routine that is repeatedly executed at regular intervals. First, in step 40, the subroutine shown in FIG. 5 is executed to calculate the acceleration/deceleration GL for the low speed range, and in the next step 50, the subroutine shown in FIG. By executing the above, the acceleration/deceleration for high speed range GH is calculated.

In the subroutine of FIG. 5, first, in step 41, it is checked whether the speed signal (2) has risen. If there is no rise, the control returns to the main routine shown in FIG. 4, but if there is a rise, the vehicle speed vL of the current cycle is calculated from the cycle T and the coefficient α shown in FIG. 3 in step 42, =α.
It is determined by the calculation of ×1/T. In the next step 43,
The vehicle speed ■, obtained in this way, and the previous vehicle speed ■, obtained in the same manner. 5. (See FIG. 3) is divided by the period T to obtain the acceleration/deceleration GL for the low speed range. Then step 4
In 4, ■, and ■. , and stored in the RAM 3 in preparation for the next cycle.

In the subroutine of FIG. 6, first, in step 51, it is checked whether the built-in timer TM indicates less than a certain predetermined time Tc. If so, the timer TM is incremented in step 52, and each time the rising edge of the speed signal ■ is detected in step 53, the number of pulses of the speed signal ■ while the timer TM is measuring is counted up in step 54. do.

When the timer TM indicates the set time T, the timer TM is cleared in step 55. Thus, the timer TM is cleared, for example, at every set time Tc shown in FIG. In addition to finding it by calculation,
The speed ■□ obtained in this manner in step 57 and the previous speed ■, obtained in the same manner. LD (see Figure 3) is divided by the set time T to find the acceleration/deceleration G)I for high speed range. Next, in step 58 ■. V ll0L
D, and set the pulse number count value p to 0.
Reset and prepare for the next time.

After the calculation of GL+GM, the control returns to step 60 of the main routine shown in FIG. 4, where it is checked whether the speed 4 of the moving object is in the high speed range (low speed range) or higher than the set speed 75. In the high speed range, in step 70, the G
)I is set to acceleration/deceleration G, and in a low speed range of V<V, the aforementioned GL is set to acceleration/deceleration G in step 80. Then, in step 90, the acceleration/deceleration G is outputted from the output control circuit 6 (see FIG. 2).

(Effects of the Invention) Thus, as described above, the device of the present invention uses the rate of change in speed determined from the pulse signal period as the acceleration/deceleration in the low speed range of the moving object, and uses the rate of change in the speed determined from the pulse signal period as the acceleration/deceleration in the high speed range of the moving object during the predetermined time of the pulse signal. Since the acceleration/deceleration is configured to be the rate of change in speed determined from the number of pulses, the calculation interval for acceleration/deceleration does not exceed the pulse signal period in the low speed range where the pulse signal period is long, which improves the responsiveness of the calculation. In the high speed range where the pulse signal period becomes short, the acceleration/deceleration calculation interval is kept at a predetermined time regardless of the short pulse signal period, resulting in poor acceleration/deceleration calculation accuracy. It is possible to prevent this from happening. Therefore, acceleration and deceleration can be calculated over the entire speed range without causing a response delay or a decrease in accuracy.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of the acceleration/deceleration calculation device of the present invention, FIG. 2 is a block diagram showing an embodiment of the device of the present invention, FIG. 3 is an output waveform diagram of the speed sensor in the same example, and FIGS. FIG. 6 is a flowchart showing the control program of the microcomputer in the same example. 1... Microcomputer 2... Central processing unit) (CPU) 3... Random access memory (RAM) 4... Read only memory (ROM) 5... Input control circuit 6... Output control Circuit 7…Speed sensor autopsy ↓” ・Cough

Claims (1)

[Claims] 1. In a device for calculating the acceleration/deceleration of a moving object from a pulse signal of a frequency corresponding to the speed of the moving object whose acceleration/deceleration is to be determined, a first device whose acceleration/deceleration is a rate of change in the speed determined from the period of the pulse signal; a second acceleration/deceleration calculation means whose acceleration/deceleration is an acceleration/deceleration rate determined from the number of pulses of the pulse signal during a predetermined period of time; An acceleration/deceleration calculation device comprising: a switching means for using the calculation value from the acceleration/deceleration calculation means, and for using the calculation value from the second acceleration/deceleration calculation means while the speed of the moving object is high.