JPH0665247B2 - Direction control method of mobile agricultural machine using wave type sensor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a direction control method for a mobile agricultural machine such as a combine, and more specifically, a wave type sensor such as an ultrasonic sensor is provided at the front of the machine body, and the sensor is used. The receiving part of the sensor receives the reflected wave from the grain culm of the wave emitted from the starting part of the sensor, measures the round trip time of the wave to detect the distance between the sensor and the grain culm, and the direction of the aircraft depending on the distance The present invention relates to a direction control method for a mobile agricultural machine using a wave-type sensor that corrects and controls the temperature.

(B) Conventional technology Conventionally, the direction control at the time of mowing work of a mobile agricultural machine such as a combine is performed by installing a grain culm sensor in a divider in the front part of the machine body, and detecting the contact of the grain culm with the grain culm sensor, thereby making The relative distance to the grain culm was detected, and based on that, the orientation of the machine was corrected so that it was aligned with the row of grain culms, but this was a control method that could not predict the planting condition in the front. Therefore, depending on the condition of planting, the line could be stripped and the grain culms could not be properly cut. Therefore,
In place of the above-mentioned mechanical contact detection, a method of controlling the direction of a mobile agricultural machine while predicting the planting condition in front by utilizing the reflection phenomenon of waves such as ultrasonic waves, light or radio waves has recently been put into practical use. Is being done.

(C) Problems to be Solved by the Present Invention By the way, in the case of using the above-described wave reflection phenomenon,
For example, in the case of using ultrasonic waves, a method that faithfully counts the round-trip time of the ultrasonic waves until the ultrasonic waves are transmitted and reflected by the grain culm and is received using pulses, and the distance is detected based on this Since the directional control is performed by using, the control circuit becomes extremely complicated, and the control system is too precise and expensive for directional control of the mobile agricultural machine. Furthermore, because the control method is too precise, even reflected waves with extremely long round trip times are accurately detected and direction control is performed faithfully, and for example, reflected waves or diffuse reflection of objects in the distance due to stock loss etc. Therefore, the direction control of the machine body is performed in response to the reflected wave received with a delay, and as a result, a line deviation occurs, which causes a drawback that the direction of the mobile agricultural machine is not properly controlled.

(D) Means for Solving the Problems The present invention aims to solve the above-mentioned problems,
Measuring pulse signal generating means 30 for generating a predetermined measuring pulse signal E ₁ , ... By receiving the reflected wave by the grain culm Ia ,.
First reference signal generating means 2 for generating _first reference signals F ₁ , ... Until a _first time T ₁ elapses from the time when the wave is transmitted.
2 and the second reference signal from the _second time T ₂ after the first time T ₁ to the third time T ₃
Second reference signal generating means 23, 25, 26, 27 for generating I ₁ , ...
, The first reference signal F ₁ , ... And the measurement pulse signal E ₁ ,
... a first comparing means 31a for comparing the said second reference signal I _1, ... and the measurement pulse signal E _1, a second comparing ... and
And the first comparing means 31a.
And by the second comparing means 31b until either the first time T ₁ elapses from the time when the wave is transmitted or the second time T ₂ elapses to the third time T ₃ elapses. the measurement pulse signal E ₁ to the time zone, it is determined whether or not ... has occurred, the measurement pulse signal E _1, ... is the originating point of the wave to the first time T ₁ is passed, or When it occurs in any of the time zones from the passage of the second time T _{2 to the} passage of the third time T ₃ , the direction control is performed so that the machine body 2 is directed to an appropriate distance, and When the measurement pulse signals E ₁ , ... Are generated in other time zones, the airframe 2 is made to go straight.

(E) Action By adopting the above means, when the divider is approaching the grain culm during cutting or separated from the grain culm within a predetermined distance, the measurement pulse signal generated by the reception of the reflected wave by the grain culm is , The first reference signal is generated within the time T ₁ or the second reference signal is generated within the time T _{2 to} T ₃ , respectively. A control signal from the approaching side is output, and the aircraft is controlled to turn in a direction in which the divider moves away from the grain culm or approaches the grain culm. Then, when the divider is at an appropriate distance to the grain culm or when the sensor detects an object farther than a predetermined distance due to lack of stock or the like, the measurement pulse signal is based on the first and second reference values. to be generated in the generation period outside the time T ₁ through T ₂ or in a time T ₃ after the signal, the control signal for turning control body is not output at all, the aircraft will not receive any direction control, as grain Go straight along the culm.

(F) Examples Hereinafter, examples in which the present invention is embodied will be described.

As shown in FIG. 1, the combine 1 has a pre-processing unit 6 in which a divider 3, a grain culm raising device 5 and the like are arranged in the front part of the machine body 2. Inside the divider 3 on the side, as shown in FIG. 4, ultrasonic waves for measuring the distance to the grain stem so that the combine 1 is controlled along the grain lines I, II .. Sensor 7
Is installed to emit ultrasonic waves diagonally forward. The sensor 7 is composed of a transmitting unit 9 that emits an ultrasonic wave, such as a sounding body, and a receiving unit 10 that has a microphone that receives the ultrasonic wave reflected by the grain stem. The section 10 is housed in each of the tubular tubes 11 and 11 so as to be protected from adhesion of water droplets and dust, and to prevent diffused reflected ultrasonic waves from being received by the receiving section 10 and to improve directivity. It is configured. Further, as shown in detail in FIG. 2, a guide body 12 is attached to the tip ends of the cylindrical pipes 11 and 11 so as to substantially match the guiding direction of the divider 3 with respect to the grain culm. Etc., so that the set angle of the sensor 7 is changed and the grain culm guided by the divider 3 is caught by the sensor 7 so that the flow of the grain culm is not disturbed. Further, the sensor 7 can be attached to the rear of the raising device 5 so that the mounting angle of the sensor 7 can be adjusted with respect to the divider 3 by an appropriate mechanism, and the sensor 7 can be removed from the divider 3 when necessary and shown by a chain line in FIG. Dividers 3 for the culms, each of which is configured to obtain
The position of can be easily changed, and it is possible to deal with the field where there are many spilled culms.

Then, the transmitter 9 and the receiver 10 of the ultrasonic sensor 7 described above.
Is connected to a control unit 16 as shown in FIG. 5 which is housed inside the operation panel 15 in front of the control unit 13 of the combine 1 so that the distance between the grain stems can be measured and the direction of the machine body 6 can be controlled. It has become.

Hereinafter, the configuration and operation of the control unit 16 will be described mainly with reference to FIGS. 5 and 6.

By the drive of the oscillator 17, the ultrasonic wave signals C ₁ , C _2, ... Of a frequency suitable for detecting the grain culm are transmitted from the transmitter 9, and at that time, the ultrasonic wave signals C ₁ , C _{2 ,} . T ₀ and transmission duration t ₀ are the signal A of the multivibrator 19 and the monostable multi, respectively, in consideration of the inter-plant distance l of the grain culm to be detected (see FIG. 4) and the traveling speed of the combine 1 at the time of cutting. It is set by the signal B of 20. In addition, the ultrasonic wave transmission angle θ (see FIG. 4) is also the ultrasonic wave signal that is transmitted in consideration of the inter-plant distance l of the grain stem to be detected and the traveling speed of the combine 1 at the time of cutting.
The angles are set so that C ₁ , C _2, ... Are constantly reflected by the grain culms to be detected. On the other hand, during the period from the transmission of the ultrasonic signals C ₁ , C ₂ , ... Until the predetermined time (first time) T ₁ elapses, the monostable multi (first reference signal generating means) 22 is used. First reference signals F ₁ , F ₂ , ... Are generated. As shown in FIG. 6, the first reference signals F ₁ , F ₂ , ... Have a waveform that is turned off only during a predetermined time T ₁ . Further, similarly, the monostable multi 23 forms signals G ₁ , G ₂ ... Which are turned off for a time T ₂ after the start of the ultrasonic signals C ₁ , C _{2 ,} .
Are formed by the signals H ₁ , H ₂ , ... Which are turned off from the time when the ultrasonic signals C ₁ , C ₂ , ... Are transmitted until the predetermined time T ₃ elapses.
The signals H ₁ , H ₂ , ... Are synthesized by passing the signals G ₁ , G ₂ , ... Inverted through the inverter 26 and the signals G ′ ₁ , G ′ ₂ ,. As shown in FIG. 6, the second reference signal I _{1 is} turned off from the time ( _second time) T ₂ after the predetermined time T ₁ has elapsed to the time (third time) T _{3 has} elapsed. , I ₂ , ... Is formed. That is, the above-described monostable multi-circuits 23, 25, the inverter 26, and the OR element 27 constitute second reference signal generating means for generating the second reference signals I ₁ , I ₂ , .... The above times T ₁ , T ₂ and T ₃ are appropriately changed by operating the dial on the operation panel 15 in accordance with the setting of the distance range of the divider 3 with respect to the grain culm to be detected. I'm supposed to get it. Further, in the time chart of FIG. 6, the time T ₀ is shown to be relatively short with respect to the times T ₁ , T ₂ , and T ₃ , but this is for convenience of illustration only, and the time T ₀ is actually shown. Is sufficiently longer than the time T ₃ etc. (for example, T ₀ ≧ 2T ₃ ), and the time T ₁ , T ₂ , T ₃ is, for example, T ₁ = T ₃ −T ₂ = 3 (T ₂ −T ₁ ). Have a relationship. Then, the transmitted ultrasonic signals C ₁ , C _2, ... Are reflected by the grain culms of the strip to be detected, and the ultrasonic signals C ₁ , C _{2 ,} .
After the time T _X from the time when the signal is transmitted, the reception signals D ₁ , D ₂
However, since the signals D ₁ , D ₂ ... are attenuated and have an irregular waveform while propagating in the air, they are amplified and amplified by the amplifier 29 and the detection / waveform shaper 30.
After being shaped, the measurement pulse signals E ₁ , E _2, ... In the off state having a predetermined width are formed as shown in FIG. Thus
The generated measurement pulse signals E ₁ , E ₂ ... Are input to the first AND element 31a and the second AND element 31b, respectively,
In the first AND element 31a, it is compared with the first reference signals F ₁ , F ₂ ... And in the second AND element 31b, it is compared with the second reference signals I ₁ , I ₂ . It When the combine 1 is used for cutting, the divider 3
Is closer than the distance set to the grain I of the grain culvert as shown by the solid line a in FIG. 4 (see the EE line corresponding to the time T ₁ ), the signal is transmitted from the transmitter 9. Since the ultrasonic signal C ₁ is reflected by the grain culm Ia and the measurement panel signal E ₁ is generated within the generation time 0 to T ₁ of the first reference signal F ₁ as shown in FIG. Depending on the state, the first AND element 31a determines the approaching state of the divider 3, and the first AND element 31a outputs a pulse signal j indicating the approaching state. The pulse signal generated in this way is monostable
After being expanded to a predetermined time width by 32a and then amplified, it is input to, for example, a clutch solenoid SLr for controlling the direction of the combine 1, so that the combine 1 keeps an appropriate distance to the grain I of the grain stem. Is controlled to move away from the culm. Similarly, the divider 3 sets the separation distance range set for the grain I of the grain as shown by the one-dot chain line b in FIG. 4 (line roll, line ha corresponding to time T _{2 to} T _3). (The range sandwiched by), the measured pulse signal E ₂ is the generation time of the second reference signal I ₂ as shown in FIG.
Since it is generated in T _{2 to} T ₃ , the second AND element 31b determines the separated state of the divider 3 by the OFF state of them, and the pulse signal K indicating the separated state is output. It is expanded to a predetermined time width by the stable multi 32b, amplified next, and then input to the solenoid SLl, and the combine 1 is controlled to turn to approach an appropriate distance. Next, when the divider 3 is in the proper distance range (the range between the line Y corresponding to the time T _{1 to} T ₂ and the line rolling), the measurement pulse signal E ′ ₁ (see FIG. 6) Is generated during the times T _{1 to} T ₂ when the first reference signal F ₁ and the second reference signal I ₁ in the off state are not present, the first AND element 31a
And the second AND element 31b does not output any control pulse, so that the combine 1 does not receive any direction control and keeps the straight state along the grain I of the grain. In this case, the fourth
Even if the divider 3 is located within the proper distance range as shown by the solid line c in the figure, in the case where the divider 3 is obliquely intersecting with the grain I, the above-described turning control is executed. Needless to say. Additionally, divider 3 is controlled subject to distance - when in (Senha corresponding to the time T ₃ distance outside Hayori), again measured pulse signal E "1 _(see FIG. 6) is in the OFF state the Since the 1st reference signal F ₁ and the 2nd reference signal I ₁ are generated after the time T _{3 when} they do not exist, the combine 1 maintains the straight traveling state. The control is actually controlled by the divider 3 on the grain stalk I.
While traveling straight along the appropriate distance range along the line, for example, the grain culm Ia of Article I is missing and the ultrasonic signal is
If a grain culm IIa, etc. of Article II passing through is detected,
Alternatively, it is executed when the ultrasonic signal is diffusely reflected and received by the receiving unit 10 with a considerable delay.

(G) Effect of the Invention As described above, according to the present invention, as a method for determining whether or not the distance between the sensor grains is within a predetermined range,
After the reference signal F ₁ , ... Is generated for a predetermined time (for example, T ₁ ) with respect to the time point when the wave is transmitted, the reference signal F
_1, ... and the measurement pulse signal E _1, the measurement pulse signal E ₁ within the predetermined time by comparing ... and, since ... has adopted a method of determining whether generated easily using only gate element A control circuit can be configured, which facilitates integration, resulting in small size and low cost. That is, when the time difference between the generation time of the measurement pulse signal E ₁ , ... And the wave transmission time is calculated and then the time difference is compared with the reference signal, an integrating circuit such as a pulse width voltage converter is required. , Because it is necessary to take timing with respect to the pulse signal, the circuit configuration becomes complicated,
Further, if the timing is deviated, control accuracy error occurs, but the present invention does not require such an integrating circuit, so the circuit configuration is simple and there is no accuracy error.

Further, the time for generating the first reference signal F ₁ is T ₁ , the time for generating the second reference signal I ₁ is T _{2 to} T ₃ , and the time T ₂ is later than the time T _1. And time T ₁ ~
The aircraft was made to go straight with T ₂ as an appropriate time (appropriate distance). Therefore, this appropriate time (appropriate distance) has a certain width and acts as a kind of dead zone, so that there is no problem such that the mobile agricultural machine is finely controlled and the riding comfort is deteriorated.

Further, when the detected distance is a short distance and a long distance, the direction control is performed so that the aircraft is directed to an appropriate distance, and when the detected distance is an appropriate distance and an out-of-control distance, the aircraft is moved straight. As a result, in the normal culm state, the aircraft is always properly controlled in direction, and even if streak streaks occur in the grain culm, or if the irregularly reflected waves are detected, there will be no disturbance to those disturbances. Without being affected, the aircraft is stably and appropriately controlled for traveling.

[Brief description of drawings]

FIG. 1 is a partial plan view of a mobile agricultural machine to which the present invention is applied,
The figure shows a side view of the sensor seen from the direction of the arrow X in FIG.
FIG. 4 is a partial side view of the pretreatment unit as seen from the direction of arrow Y in FIG. 1, FIG. 4 is a diagram showing the positional relationship between the sensor on the divider and the grain stem, and FIG. FIG. 6 is a block diagram showing an example, and FIG. 6 is a time chart of each signal in the control block shown in FIG. 1 ... Mobile agricultural machine (combine), 2 ... Airframe, 7 ... Wave type sensor, 9 ... Transmitting section, 10 ... Receiving section, 22 ... First
Reference signal generating means (monostable multi), 23 ... Second reference signal generating means (monostable multi), 25 ... Second reference signal generating means (monostable multi), 26 ... Second reference Signal generating means (inverter), 27 ... Second reference signal generating means (OR element), 30 ... Measurement pulse signal generating means (detection / waveform shaper), 31a ... First comparing means (first AND element), 31b ... second comparing means (second AND element),
C: outgoing signal, D: received signal, I, II ... grain culm strip,
E ... Measured pulse signal, F ... First reference signal, I ...
Second reference signal

Claims (2)

[Claims] 1. A wave-type sensor is provided in a front part of an airframe, and a wave reflected from a grain stem of a wave emitted from a transmitting portion of the sensor is received by a receiving portion of the sensor to detect a distance between the sensor and the grain stem. Then, in the direction control method of the mobile agricultural machine adapted to correct the direction of the machine body according to the distance, a measurement pulse signal generating means for generating a predetermined measurement pulse signal by receiving a reflected wave by the grain stem, and the wave The first time from the time the call was sent to the first time
First reference signal generating means for generating the second reference signal, and a second reference signal generating means for generating the second reference signal from the second time after the first time to the third time.
Reference signal generating means, first comparing means for comparing the first reference signal with the measurement pulse signal, and second comparing means for comparing the second reference signal with the measurement pulse signal. , And by these first comparing means and second comparing means,
It is determined whether or not the measurement pulse signal is generated from a time point at which the wave is transmitted until a first time period elapses, or at a time period from when the second time period elapses to when the third time period elapses. However, in the case where the measurement pulse signal is generated in any one of the time period from the time when the wave is transmitted until the first time elapses or from the time when the second time elapses to the time when the third time elapses. In the wave type, the aircraft is controlled so that the aircraft is directed to an appropriate distance, and when the measurement pulse signal is generated in other time zones, the aircraft is moved straight. Direction control method of mobile agricultural machine using sensor. 2. The wave type sensor has a transmitter that emits ultrasonic waves, a receiver that receives the reflected ultrasonic waves, and a tubular tube that houses these transmitters and receivers. The direction control method for a mobile agricultural machine using a wave-type sensor according to claim 1, wherein the diffusely reflected ultrasonic waves are hard to be received and have directivity.