JP3473203B2 - Fruit harvesting hand - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fruit harvesting manipulator for an automatic fruit harvesting machine that automatically controls a fruit harvesting manipulator based on visual information of a visual sensor to harvest fruits. Regarding the fruit harvest hand. [0002] When harvesting fruits by visual information of a visual sensor, if the fruits taken into the fingers of the fruit harvesting hand are inclined in the depth direction,
The fruit will be damaged when cutting the stem. However, it is very difficult to detect the state of the fruit taken into the finger of the fruit harvesting hand in the depth direction, particularly with one visual sensor. According to the present invention, by providing a sensor for detecting the state of the fruit taken in the finger in the depth direction and appropriately controlling the posture of the fruit harvesting hand, the fruit is not damaged when cutting the fruit handle. It is intended to do so. [0004] In order to achieve the above object, the present invention is configured as follows. That is, in a fruit harvesting hand of a fruit harvesting manipulator that automatically harvests fruits such as cucumbers based on visual information of a visual sensor, a sensor for detecting a depth inclination angle of a fruit taken into a finger of the fruit harvesting hand. The fruit harvesting hand is characterized in that the fruit harvesting hand is cut by controlling the posture of the fruit harvesting hand at an angle substantially perpendicular to the central axis of the fruit taken into the finger by the signal of the sensor. Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a plan view and a side view of a fruit harvesting hand according to the present invention. The fruit harvesting hand 1 is provided with two sets of fruit presence / absence sensors 4 and 5 at both ends of two fingers 2 and 3. Fruit presence sensor 4 provided on one finger 2
Is a light emitting side, and the fruit presence / absence sensor 5 provided on the other finger 3 is a light receiving side. Two fruit center axis detection sensors 8 and 9 having a light emitting unit 6 and a light receiving unit 7 are provided above and below the center of one finger 2. At the upper center of the two fingers 2 and 3 on the side of the fruit harvesting hand 1, there is provided a fruit pattern detecting sensor 12 having a light emitting unit 10 in the center and light receiving units 11 on both sides thereof. The fruit harvesting hand 1 is configured as described above, detects the inclination angle of the fruit 13 taken into the two fingers 2 and 3 in the depth direction, controls the posture of the fruit harvesting hand 1, and then controls the fruit handle 14. Disconnect. The attitude control process of the fruit harvesting hand 1 will be described with reference to a flowchart shown in FIG.
When the process is started (step 101), first, the fruit presence / absence sensors 4 and 5 detect whether or not the fruit 13 has entered the two fingers 2 and 3 of the fruit harvesting hand 1 (step 102). If so, the process returns to step 102. If so, it is detected whether or not the central axis of the fruit 13 coincides with the line connecting the two fruit central axis detection sensors 8 and 9 (step 103). If they coincide, the process is terminated (step 104). If they do not match, it is determined whether the fruit 13 is inclined in the depth direction or in the front direction (step 105). If it is inclined in the depth direction, the list of the fruit harvesting hand 1 is corrected in the depth direction (step 106), and as a result of the correction, the center axis of the fruit 13 is 2
It is detected whether or not the line coincides with the line connecting the two fruit center axis detection sensors 8 and 9 (step 107). If the line coincides, the process is terminated (step 104), and if not, the process returns to step 106 again. If it is inclined in the forward direction, the list of the fruit harvesting hand 1 is corrected to the forward direction (step 1).
08), as a result of the correction, it is detected whether or not the center axis of the fruit 13 matches the line connecting the two fruit center axis detection sensors 8 and 9 (step 109), and if they match, the process is terminated (step 104). ), If not, step 1 again
Return to 08. Next, in connection with the present invention, a fruit harvesting hand that detects fruit contact from a change in load current of a gripping motor that drives a finger and controls an appropriate gripping force of the finger based on the contact will be described. FIG. 4 shows a schematic configuration diagram of this fruit harvesting hand. The fruit harvesting hand 1 attaches two fingers 2 and 3 to a screw rod 15 having different screw directions on the left and right, rotates the gripping motor 16 forward and reverse to move the two fingers 2 and 3 closer to and away from the fruit 13. To grip. FIG. 5 shows a time change of the load current of the gripping motor 16, and a first-order and second-order derivative curve thereof. In the figure, a is the current value when the fingers 2 and 3 come into contact with the fruit 13, and b is the current value when the fingers 2 and 3 complete grasping the fruit 13. In the figure, up to a represents the time change of the no-load current, from a to b represents the time change of the load current until the completion of gripping, and thereafter represents the time change of the lock current. In this fruit harvesting hand, the peak current value obtained by secondarily differentiating the load current of the gripping motor 16 is defined as a, and this is the position where the fingers 2 and 3 are in contact with the fruit 13, and the thickness of the fruit 13 is determined from this. . Further, the current value b at the completion of grasping is obtained by the following formula. b = a + α · a Here, α is a preset constant. By the load current value of gripping completion obtained here, until gripping completion,
When lifting a petiole or the like in order to cut a fruit handle, the amount of movement of the finger for providing a gripping force that does not cause the fruit being gripped to fall off is controlled. This fruit harvesting hand detects the thickness of the fruit and controls the appropriate gripping force by changing the load current of the gripping motor that drives the finger. Therefore, a sensor or the like for detecting the thickness of the fruit is not required, and the device can be reduced in size and weight. Therefore, the fruit harvesting hand can be put in a narrow place, and the fruit harvesting efficiency can be improved. Further, it is possible to cope with a variation in finger driving load due to a variation in the body, and it is also possible to detect a mechanical failure such as a mechanical lock. Next, in connection with the present invention, a fruit harvesting hand for estimating a fruit cutting condition from a load current pattern of a fruit cutting motor will be described. FIG. 6 shows a load current pattern of the stalk cutting motor. In the drawing, ta indicates the range of the operation check time of the cutting mechanism, tb indicates the range of the cutting state check time, and ia indicates the range of the peak current at the time of normal cutting. Further, i1 is a cutting mechanism failure pattern due to a lock or the like, i2 is a non-cutting pattern such as a fruit pattern that cannot be cut,
i3 represents a normal cutting pattern, and i4 represents a non-cutting pattern due to escape of fruit. With reference to the flowchart shown in FIG. 7, the processing for estimating the cutting status of the fruit handle will be described. When the process is started (Step 201), first, an operation check timer of the cutting mechanism is set (Step 202), and the cutting motor is turned on (Step 203). When the operation check timer times out (step 204), the load current is measured (step 205). It is determined whether the load current is in the locked state (step 206). If the load current is in the locked state, the cutting motor is turned off (step 20).
7) Inform the operator of the inspection (step 20)
8), end the process (step 209). If not locked, the load current is measured (step 210),
The peak value of the current is searched (step 211), and it is determined whether or not the peak value is equal to or more than the set value (step 212). If not, the cutting motor is turned off (step 213), and the process ends. (Step 214). If it is equal to or greater than the set value, the disconnection status check timer is set (step 215). When the disconnection status check timer times out (step 216), the load current is measured (step 217). It is determined whether the load current is normal (step 218). If not, the cutting motor is turned off (step 219), and the process is terminated (step 220). If normal, the cutting motor is turned off (step 221), the cutting section is returned to the initial position (step 222), and the process is terminated (step 223). This fruit harvesting hand estimates the cutting state of a fruit handle by using a phenomenon in which a load current pattern when cutting a fruit handle is different from a load current pattern when cutting is impossible. Therefore, at the time of normal cutting, control is transferred to the carry of the fruit,
When cutting is not possible, the next control can be easily determined depending on the cutting condition of the fruit stem, such as stopping the harvesting operation and notifying the operator of the inspection. Next, in connection with the present invention, the thickness of the object in the finger is determined from the detection time of the fruit sensor in the finger and the amount of extension of the manipulator. A fruit harvesting hand for preventing cutting will be described. FIG. 8 shows a cumulative time transition of the extension amount of the manipulator tip and a waveform diagram of the fruit sensor signal. In the figure, ts represents the detection time of the fruit sensor, and the extension amount during this time is integrated to obtain the thickness of the object in the finger. The erroneous cutting prevention processing will be described with reference to the flowchart shown in FIG. When the process is started (step 301), the approach is adjusted first (step 302), and a timer is set (step 30).
3) The approach is performed (step 304), and it is determined whether there is a fruit in the finger (step 30).
5) If not, return to step 304. If there is fruit in the finger, stop the timer (step 30).
6), the thickness of the object in the finger is calculated by integrating the extension of the detection time of the fruit sensor (step 307), and the thickness is corrected by the manipulator angle (step 30).
8). Next, the thickness is determined, and if it is not a petiole (step 309), but a fruit (step 310), and if it is a harvestable fruit (step 311), harvest processing is performed (step 312), and the timer is reset. (Step 3
13), end the process (step 314). In the case of a manipulator of the pantograph type or the like, since the extension amount of the tip with respect to time is non-linear, the thickness of the fruit is measured only while the fruit sensor in the fruit harvesting hand detects the fruit. It is impossible. In this fruit harvesting hand, the thickness of the fruit is calculated in consideration of the extension amount of the tip of the manipulator, so that the thickness of the fruit can be measured with high accuracy. This measurement method is particularly effective when the distance to the object is unclear. Next, in connection with the present invention, a fruit harvesting hand will be described in which a center of rotation is provided in the hand and the hand is rotated left and right and up and down to harvest fruits. 10 and 11
Figure 2 shows a plan view and a side view of the fruit harvesting hand. In this fruit harvesting hand, the hand is rotated left and right by a left and right rotation motor 17 and is rotated vertically by a vertical rotation motor 18 around a rotation center k of the hand. Conventionally, the boundary between the manipulator and the hand is set at the center of rotation k of the vertical rotation of the hand. Therefore, the moment of inertia is large, and a large motor capacity is required to rotate the hand several tens of degrees within several hundred ms. And Therefore, the size of the motor is increased, and it is difficult to reduce the size and weight of the motor. This fruit harvesting hand has a small moment of inertia because the center of rotation k of vertical rotation is within the hand.
The vertical rotation motor 18 can be made smaller. Also,
As shown in FIG. 12, since the distance between the linear motion direction and the vertical direction at the time of the linear motion approach can be shortened, the speed of cutting the stem at the time of harvesting can be increased. Next, in connection with the present invention, a fruit harvesting hand provided with a petiole removing device that moves up and down in the upper part of a finger will be described. FIG. 13 shows a schematic configuration diagram of this fruit harvesting hand. This fruit harvesting hand is a lifting motor 1
9 is driven to rotate the ball screw 20, and the petiole removing portion 21 provided above the finger portions 2, 3 is moved up and down. Referring to the flowchart shown in FIG.
The process of removing the petiole of the fruit harvesting hand will be described.
When the process is started (step 401), it is first determined whether or not the fruit has been gripped (step 402). If the grip has been completed, it is determined whether or not there is an obstacle in the fruit handle (step 403). If there is, the petiole removing unit 21 is raised (step 404). Next, it is determined whether or not a fruit pattern has been detected (step 405).
Return to step 404. If a fruit handle has been detected, the petiole removal unit 21 is stopped (step 406), and the process is terminated (step 407). At the time of cutting the stem, if there is a petiole or stem in front of the stem, the fruit cannot be harvested, and the harvesting efficiency is reduced. In this fruit harvesting hand, when the fingers 2 and 3 grip the fruit, the petiole removing section 21 rises and removes the petiole or stem in front of the fruit handle, thereby preventing erroneous cutting and improving the harvesting efficiency. it can. Next, in connection with the present invention, a description will be given of a fruit transporting apparatus in which an inclined plate for transporting harvested fruits to a carry is made stretchable. FIG. 15 and FIG. 16 show a front view and a side view of the fruit conveying device. When the carry 22 is full of fruits, the fruit transport device discharges the carry 22 to the outside of the machine and drops the next carry 22 from above to supply the carry 22. At this time, the inclined plate 23 provided above the carry 22 is in the way,
By rotating the winding unit 24, the inclined plate 23 is wound and the upper surface of the carry 22 is opened. Therefore, the inclined plate 2
3 without disturbing, with such a simple mechanical configuration,
The next carry 22 can be supplied. Next, a description will be given of a fruit conveying device in which a fruit detecting sensor 25 is attached to the tip of the inclined plate 23 shown in FIGS. 15 and 16, and the inclination angle and the plate length of the inclined plate 23 are controlled by the signal of this sensor. As shown in FIG. 17, the inclination angle of the inclination plate 23 is
The pressure lever 26 attached to the rotating shaft of No. 4 is rotated up and down to adjust and control the pressure applied to the inclined plate 23. The plate length of the inclined plate 23 is
The winding amount of the inclined plate 23 by the rotation of 4 is adjusted and controlled. This fruit transport device is designed to fall the harvested fruit on the inclined plate 23 and accommodate it in the carry 22. At this time, the fruit loading state is detected by the fruit detection sensor 25, and the inclination angle and the plate length of the inclined plate 23 are adjusted according to the progress of the fruit loading so that the fruit loading is uniform from the back of the carry 22 to the front. While adjusting, house the fruit. Therefore, since the fruits stored in the carry 22 are uniformly loaded, the variation in the amount of stored fruits can be reduced, and the carry 22 does not become unbalanced when it is full, and when the carry 22 is discharged outside the machine,
It is possible to prevent an accident in which the carry 22 falls down. Next, in connection with the present invention, a carry discharge device for opening and closing two support plates on which a carry is placed to discharge a full carry will be described. 18 and 19 show a front view and a side view of the carry discharge device. This carry discharge device is provided with two support plates 27a and 27b on which the carry 22 is placed, and belts 30a and 30b are provided between the rotating shafts 28a and 28b of the support plates 27a and 27b and the rotating plates 29a and 29b. Hang over. Turntables 29a, 29b
The gears 31a and 31b which mesh with each other and rotate coaxially with the rotating discs 29a and 29b are attached to the rotating shafts. Gear 31
An opening / closing motor 32 is attached to the rotating shaft b, and the opening / closing motor 32 is driven to rotate the two rotating shafts 28a and 28b in opposite directions to open and close the support plates 27a and 27b. As shown in FIG. 20, in this carry discharge device, when the support plates 27a and 27b are opened during traveling, the rear part of the carry 22 in the traveling direction falls and contacts the ground. Next, the remaining front part in the traveling direction also falls as the vehicle travels, and the entire part touches the ground. Since the carry discharge device discharges the carry 22 by utilizing the movement of the body, the carry 22 can be completely discharged out of the machine with a simple mechanism. Also,
Since the carry 22 falls separately in two stages of the rear part and the front part in the traveling direction, the impact given to the fruit can be reduced. Next, the carry drop buffering mechanism of the carry discharge device will be described. This cushioning mechanism is shown in FIG.
As shown in FIG. 7, a buffer spring 33 is bridged between the support plates 27a and 27b, and the impact of the drop of the carry 22 is absorbed by the expansion and contraction of the buffer spring 33. When the support plates 27a and 27b are opened during traveling and the carry 22 is dropped, the impact at the front part in the next traveling direction is particularly large compared with the drop at the rear part in the first traveling direction.
The buffer mechanism reduces the falling speed of the forward portion in the traveling direction by the buffer spring 33, so that the impact of the drop of the carry 22 is absorbed and the damage of the fruit is prevented. Next, in connection with the present invention, a fruit harvester that expands and contracts a fruit guide for harvesting a shelf-shaped crop and guiding it to a carry in accordance with a height-direction harvesting position will be described. As shown in FIG. 22, the fruit harvester includes a fruit guide 35 for guiding fruits to the carry 22 on an attachment plate 34 of the fruit harvesting hand 1.
Of fruit inputs. The mounting plate 34 includes a feed screw 36
And the guide rail 37, and drives the elevating motor 38 to rotate the feed screw 36 forward and backward. Thereby, the mounting plate 34 is slid up and down along the guide rail 37. The fruit guide 35 is formed as a bellows, and expands and contracts in accordance with the movement of the mounting plate 34. In this fruit harvester, the fruit guide 35 expands and contracts in accordance with the movement of the mounting plate 34, so that the fruit harvesting hand 1 and the fruit inlet of the fruit guide 35 always maintain a fixed positional relationship. Therefore, even if the harvesting position is raised, the harvested fruit can be put into the carry 22 without sliding down the mounting plate 34 of the fruit harvesting hand 1, and the fruit harvesting efficiency can be improved. Next, in connection with the present invention, a self-propelled machine which knows the headland turning start in the house by the turning point detecting sensor and knows the turning completion by the output ratio or the output difference of the guide line detecting sensors provided on the left and right. explain. As shown in FIG. 23, this self-propelled machine has a guide wire 39 installed on the ceiling of the house.
Travel under. The guide line 39 changes its direction by 90 ° to the right from the straight traveling portion 39a and moves to the turning portion 39b. Guide line detection sensors 40L and 40R are provided at the front left and right of the upper part of the vehicle body, and a turning point detection sensor 41 is provided at the center of the lower part of the vehicle body.
The guide line detection sensors 40L and 40R receive magnetic flux of the guide wire 39 through which current flows to generate magnetic induction power, and the turning point detection sensor 41 detects metal buried at the turning point A to know the turning point. Guide line detection sensor 40 installed in self-propelled machine
The output voltage corresponding to the displacement of L and 40R from the induction wire 39 changes as shown in FIG. L1 and R1 in FIG.
Guidance line detection sensor 40 for displacement from linear portion 39a
L, represents the output voltage of 40R. R2 represents the output voltage of the guide line detection sensor 40R with respect to the displacement from the turning portion 39b. R3 is the output voltage of the guide line detection sensor 40R with respect to the displacement from the rectilinear portion 39a and the turning portion 39b when the self-propelled vehicle approaches the turning point A, and is a value obtained by combining R1 and R2. Referring to the flowchart shown in FIG.
The headland turning process of the self-propelled machine will be described. When the process is started (step 501), first, it is determined whether or not the ridge end of the turning point A has been detected (step 502). When the ridge end has been detected, it is determined whether or not a right turn has been performed (step 50).
3) If it is a right turn, the self-propelled machine turns right (step 504), and the output ratio or output difference between the guide line detection sensors 40L and 40R is calculated (step 505), and the value is set to a set value. Is determined (step 506).
If not equal, return to step 504; if equal,
The turning is stopped (step 507), and the process ends (step 508). If it is not a right turn, the self-propelled machine turns left (step 509), and the guidance line detection sensor 40L
Calculate the output ratio or output difference of 40R (step 5
10), it is determined whether or not the value is equal to the set value (step 511). If not equal, the process returns to step 509; otherwise, the process proceeds to step 507. In this self-propelled machine, the left and right guide line detection sensors used for straight running control during running between ridges are also used for turning control. Therefore, the number of sensors is reduced to simplify the entire system, and low cost and high reliability are realized. The fruit harvesting hand of the present invention has the above-described configuration, and is provided with a sensor for detecting the state of the fruit taken in the finger in the depth direction to appropriately control the posture of the fruit harvesting hand. . Therefore, according to the present invention, the state in the depth direction of the fruit taken into the finger, which has been ambiguous in the past, is clarified, and therefore, the stalk can be detected with high accuracy, and the proper state is adjusted according to the state of the fruit. By cutting the peduncle in a posture, the fruit can be prevented from being damaged.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a fruit harvesting hand according to the present invention. FIG. 2 is a side view of the fruit harvesting hand of the present invention. FIG. 3 is a flowchart of a posture control process of the fruit harvesting hand according to the present invention. FIG. 4 is a schematic configuration diagram of a fruit harvesting hand. FIG. 5 is a time change graph of a load current of a gripping motor. FIG. 6 is a load current pattern of the fruit cutting motor. FIG. 7 is a flowchart of a process of estimating a fruit cutting state. FIG. 8 is a waveform diagram of a cumulative time transition of the manipulator extension amount and a fruit sensor signal. FIG. 9 is a flowchart of erroneous cutting prevention processing. FIG. 10 is a plan view of a fruit harvesting hand. FIG. 11 is a side view of the fruit harvesting hand. FIG. 12 is an approach diagram of a fruit harvesting hand. FIG. 13 is a schematic configuration diagram of a fruit harvesting hand. FIG. 14 is a flowchart of a petiole removal process of a fruit harvesting hand. FIG. 15 is a front view of the fruit transport device. FIG. 16 is a side view of the fruit conveying device. FIG. 17 is a schematic perspective view of an inclined plate. FIG. 18 is a front view of the carry discharge device. FIG. 19 is a side view of the carry discharge device. FIG. 20 is a discharge diagram of the carry discharge device. FIG. 21 is a schematic configuration diagram of a carry drop buffer mechanism. FIG. 22 is a schematic perspective view of a fruit harvester. FIG. 23 is a traveling state diagram of the self-propelled machine. FIG. 24 is an output voltage graph of the induction wire detection sensor. FIG. 25 is a flowchart of a headland turning operation of the self-propelled machine. [Description of Signs] 1 Fruit harvesting hand 2, 3 Finger 4, 5 Fruit presence sensor 6 Light emitting unit 7 Light receiving unit 8, 9 Fruit central axis detection sensor 10 Light emitting unit 11 Light receiving unit 12 Fruit pattern detection sensor 13 Fruit 14 Fruit pattern 15 Screw rod 16 Gripping motor 17 Left-right rotating motor 18 Vertical rotating motor 19 Lifting motor 20 Ball screw 21 Petiole removing section 22 Carry 23 Inclined plate 24 Winding section 25 Fruit detection sensor 26 Pressure lever 27 Support plate 28 Rotating shaft 29 Rotating disk 30 Belt 31 Gear 32 Opening / closing motor 33 Buffer spring 34 Mounting plate 35 Fruit guide 36 Feed screw 37 Guide rail 38 Elevating motor 39 Guide wire 40 Guide wire detection sensor 41 Turning point detection sensor

Claims (1)

(57) [Claims] [Claim 1] In a fruit harvesting hand of a fruit harvesting manipulator that automatically harvests fruits such as cucumbers based on visual information of a visual sensor, the fruit taken in the finger of the fruit harvesting hand is used. A sensor that detects the inclination angle in the depth direction is provided, and the signal of this sensor is used to control the posture of the fruit harvesting hand at an angle almost perpendicular to the central axis of the fruit taken into the finger and cut the fruit handle. Characterized fruit harvesting hand.