JP2016147687A - Robot for dishing food product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems about a shape of a hand for handling a food product, the shape is variously studied, a food product transport hand is decisively different from an industrial robot hand in property of a handling object such as viscous and elastic plasticity, viscosity, non-uniformity, considering the property of the food product, a study which pays attention to a piercing method by a needle is performed, a hand has a needle shape in the study, but, by the needle-shaped hand, when the food product is dished, a hole is formed on the food product, and sometimes a broken needle may enter in the food product.SOLUTION: A robot for dishing the food product to a container, can solve the above-mentioned problem.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a robot for serving food.

  In the present invention, an articulated robot system is developed with the goal of automating the work of packing side dishes. Currently, the work of packing side dishes such as commercially available lunch boxes is performed manually. This is a sanitary problem and automation is strongly desired. If the food transport system currently under study is put into practical use, it will be possible to reduce product prices not only by hygiene, but also by reducing labor costs and making quality uniform. In the present invention, a robot arm is manufactured and a method for placing a target food is devised, studied, and improved. In addition, the thing of patent document 1 is disclosed as a food arrangement | positioning robot.

JP 2003-128002 A

Naoki Sakamoto, Mitsuru Higashimori, Makoto Kaneko, “Puncture Grabbing Using Self-Tightening Effect”, The 31st Annual Conference of the Robotics Society of Japan, pp. 66, 2013.

  Currently, various studies have been conducted on the shape of hands handling food. The critical difference between the food transport hand and the industrial robot hand is the nature of the object to be handled, such as viscoelasticity, tackiness, and non-uniformity. In consideration of the properties of this food, research (Non-Patent Document 1) has been made focusing on the needle piercing method. In this research, the shape of the hand is a needle shape. However, with a needle-type hand, a hole is opened in the food when it is placed. In addition, a broken needle may enter the product. In the present invention, a method of serving the target food without damaging it is examined.

  The present invention has been conceived in view of the above problems, and more specifically, is characterized in that food is put into a container.

  In the downhill type, the fried chicken may roll after landing on the container, but in the charging type, the fried food will not rotate and will not spill out of the container.

It is a lunch container which serves food according to the present invention. It is a figure which shows the concept of experiment. It is a graph which shows the relationship between the frequency | count n of sliding and the static friction coefficient (micro | micron | mu). It is the conceptual diagram of the robot arm used for the downhill type arrangement method, and the photograph of the robot arm actually produced. It is a continuous photograph when the sliding type arrangement method is performed. It is the conceptual diagram of the robot arm which uses the throwing type arrangement method, and the photograph of the robot arm actually produced. It is a continuous photograph when the throwing type arrangement method is performed. It is a graph which shows the relationship between the position p on a board, and the flight distance q.

<Design guidelines>
A plate-like robot hand is mounted on the end of the robot arm. Start with the target food on the robot hand and place the target food in the lunch box. Also, when serving, the robot arm should not pass over the lunch box. This is for minimizing the risk of mixing into the lunch box even if parts such as screws fall from the robot arm. FIG. 1 shows a lunch box used in the present invention. The size of the container is 170 mm long and 220 mm wide. The height of the partition is 25 mm. The target food is placed in the largest left partition of the lunch box. The area of this partitioned trapezoid is 1.7 × 10 ⁴ mm ² .

<Selection of target food>
In the present invention, foods mainly handled are selected. In this report, we will examine how to prepare foods that are considered the easiest to prepare and prepare. As foods that are considered to be the easiest to serve, select solids that have no fixed orientation when they are served. Moreover, since it is a foodstuff, replacement of the target food must be frequently performed. Therefore, considering whether it can be easily obtained at a grocery store or the like, in the present invention, it has been decided to mainly handle fried chicken thighs.

<Selection of hand materials and characteristics of target food>
The coefficient of static friction of 10 fried chickens on the market was measured. The average mass of fried chicken was 20.9 g. Since handling fried chicken, we select a material that is oil resistant and has a smaller coefficient of static friction as the material for the hand. Thereby, sliding conveyance using the upper surface of the hand is possible. Therefore, the coefficient of static friction of plastic, aluminum and acrylic with oil resistance was measured. FIG. 2 shows a conceptual diagram of the experiment. One fried chicken is put on each plate, then the plate is tilted, and the angle of the plate is calculated from the height h and the length L of the plate from which the fried food starts to slide.

The static friction coefficient ν is calculated from the angle of the plate. The calculation formula is shown in Formula (1).
ν = tan (sin ⁻¹ (h / L)) (1)

This experiment was carried out 100 times a total of 10 times on both sides of the fried 10 pieces. Table 1 shows the average value of the coefficient of static friction.

As shown in Table 1, the coefficient of static friction of aluminum was the smallest. Thereafter, aluminum is used as the material of the hand. In addition, it was examined how the coefficient of static friction changes when a fried chicken is slid continuously. The static friction coefficient was calculated in the same manner as described above using an aluminum plate. FIG. 3 is a graph showing the relationship between the number n of sliding and the static friction coefficient μ. The equation of the approximate line is expressed as equation (2).
μ = 2.3 × 10 ⁻³ n + 3.5 × 10 ⁻¹ (2)
From this equation, it can be seen that the friction coefficient increases as the number of times of sliding increases.

<Examination of arrangement method>
There are two ways to use a robot arm to place fried chicken in a lunch box. This time, an aluminum plate was used as the robot hand. A series of operations for placing the target object in the container after the target object placed on the plate-like hand is moved to the vicinity of the container will be referred to as placing.

<Downhill type>
The downhill type laying method is a laying method in which a plate-like hand is tilted and placed so that the fried food is slid and moved. In this hand, an aluminum hand having a length of 140 mm and a width of 55 mm was used. FIG. 4 shows a conceptual diagram of a robot arm used in the downhill type arrangement method and a photograph of the actually manufactured robot arm. This robot arm has two degrees of freedom.

  This robot system is the first prototype. FIG. 5 shows a series of photographs when the sliding type arrangement method is performed using the first prototype. The advantage of the sliding type is that it can be realized if the robot arm has two degrees of freedom. The fact that it can be realized with a small degree of freedom means that the number of motors in the entire robot arm is reduced, and the robot arm can be manufactured at a low weight and at a low cost.

  However, when the downhill-type arrangement method was actually tried, there was a problem that the fried chicken rolls or slips on the lunch box. The reason why fried chicken rolls is that the fried food is rotated by the moment when the fried chicken comes to the end of the aluminum plate at a low speed.

<Input type>
The throwing type laying method is a laying method in which fried chicken is thrown into a container by quickly driving a plate-like hand with a motor. This time, an aluminum hand 70 mm long and 55 mm wide was used. We think that it is desirable to have more than 3 degrees of freedom in order to smoothly feed the fried food without rotating it using the throwing type arrangement method.

  FIG. 6 shows a conceptual diagram of a robot arm that uses the throwing type arrangement method and a photograph of the robot arm that was actually manufactured. This robot arm has four degrees of freedom. This robot system is the second prototype. FIG. 7 is a series of photographs when the throw-in type arrangement method is performed using the prototype No. 2 machine.

Compared with the sliding type arrangement method, the throwing type arrangement method has a lower possibility that the fried food will rotate or slide on the container. FIG. 8 shows the relationship between the position p on the plate and the flight distance q. The outer edge of the plate is the reference (0 mm). At each position, an aluminum cube having a mass of 22 g and a side of 20 mm was blown five times, and the average value of the horizontal flight distance was graphed. The horizontal flight distance starts from the position of fried food on the board. The equation of the approximate line is as shown in equation (3).
q = −5.1p + 1.9 × 10 ² (3)
From this, it can be seen that the closer to the reference position (0 mm), the longer the flight distance.

  In the present invention, a downhill type and a throw-in type arrangement method have been devised. The devised arrangement method was examined using prototype No. 1 and No. 2. In the downhill type, the fried chicken may roll after landing on the container. However, it was improved by the input type device. With the dough-type serving method, the fried food does not rotate, so it may be possible to handle foods that have a specific orientation when they are placed in a container.

  The present invention can be suitably used for serving food.

Claims (1)

A food placement robot characterized by feeding food into a container.