Automatic Dust Catcher Robot of Clothes with Brush Cleaning Function

If you come into contact with others with dust or animal hair on your clothes, there is a high possibility that you will make the other person develop an allergy or not be able to establish good communication. Thus, it is necessary to remove dusts and more from your clothes before going out. However, this work is done manually, which is time-consuming and time-consuming. To solve this problem, in the past we developed a robot that automatically removes dust from clothes on hangers with a brush. The robot holds and pinches the clothes between two brushes and removes the dust by moving the brushes from top to bottom. It also removes dust from the entire clothes by repeatedly extending the arm with the brush attached and removing the dust. However, with this robot, cleaning the dirty brushes must be done manually. Thus, we added a device to this robot that automatically cleans the brushes. With the addition of this device, the user will not have to clean the brushes after using the robot. All the user has to do is put the clothes on the hanger, press the start button on the robot, and the robot will remove the dust from the clothes. While the robot is running, the user can spend his time doing other things. For example, by using this robot, you can make better use of your valuable morning time for yourself instead of using it to dust your clothes.


Introduction
House dust, mites, and animals can cause allergies (1) (2) . It is dangerous to come in contact with allergy sufferers with these substances on your clothes (3) (4) . Therefore, it is necessary to remove dust and other particles from clothes when there is a possibility of contacting with people.
Also, appearance is a quite important point in giving a positive impression on others (5) . According to the questionnaire on marriage activities conducted in 2020 by Partner Agent, a dating agency operated by Tameny Corporation says 48.4% of men and 65.0% women of 978 men and women aged 30-39 who have done marriage activities ranked appearance and cleanliness as the most important factor in determining the impression of a partner or the factor that makes a good impression in marriage activities (6) . This is the most common answer for both men and women. Thus, we need to wear clean clothes. In order to wear clean clothes, it is necessary to wash, iron out wrinkles, and remove dust from clothes. In this paper, we focused on the task of removing dust from clothes.
Many people have pets. According to the national survey of the Pet Food Association's in 2020, 6.8 million households have 8.49 million dogs and 5.51 million households have 9.64 million cats (7) . Many pet owners are  troubled by their pets' hair loss (8) (9) .
Dust and animal hair on clothes are mostly removed by using rolls of adhesive tape, special brushes, and other useful items. However, these need to be done manually, which can be a big burden if you have a lot of clothes or if you have a dog or cat.
Many people spend a lot of time grooming themselves in the morning before going to work (10) . And many people feel that they don't have time in the morning (11) .
In the past, we have developed robot that can operate continuously on multiple clothes (12) . The robot holds clothes on a rotating hanger rack between two brushes and removes dust by moving the brushes from top to bottom, then extends the brushes and repeats the above operation to remove dust of the entire clothes. In addition, by rotating the hanger rack, it is possible to remove dust of multiple pieces of clothes. In this paper, a system has been installed on the robot to clean the brushes used for the task after removing dust of the clothes. The system uses a servo motor to rotate an additionally installed brush to remove dust from the brushes that have been tasked with removing dust of clothes.
By using this robot, you can save time and effort by removing dusts. The user can use the time that would otherwise be consumed for removing dust of clothes for other things. For example, by using this robot, the user can use valuable time in the morning not for removing dust of clothes, but for oneself.

Automatic Dust Catcher Robot of Clothes with Brush Cleaning Function
In this paper, we have developed a robot that can automatically remove dust of multiple pieces of clothing and brushes. A schematic diagram of the robot is shown in Fig. 1. The robot can be divided into two parts: the rotating hanger rack on the right side of Fig. 1 and the robot's main body on the left side, which is responsible for removing dust of the clothes and brushes.
First, a rotating hanger rack is rotated. Using Kinect and image processing, the clothes are placed in front of the robot's main body (12) . Next, the robot's main body controls two brushes to remove dust from clothes. Once the dust has been removed from the clothes, the brushes are cleaned. Finally, rotate the hanger rack again. By repeating the above process, it is possible to perform removing dust on multiple pieces of clothing in succession.
An overview of the operation of the robot's main body is shown in sections 2.1~2.2.

The operation of removing dust of clothes
The robot's main body on the left side of Fig. 1 is used to remove dust from clothes. A schematic diagram of the robot's main body is shown in Fig. 2. This robot can hold clothes between two brushes and move them up and down to remove dust from the clothes. Extend the brush and repeat the above operation to remove dust from the entire clothes. From Fig. 2, each moving part corresponds to the following axis: red for holding the clothes between the brushes, blue for moving the brushes up and down to remove dust from the clothes, and yellow for extending the brushes to remove dust from the whole clothes. The moving parts move in the  direction of the arrows, respectively. When clothes are placed in front of the robot's main body, the robot's main body starts removing dust of the clothes. Once the operation starts, the robot's main body repeatedly moves its three axes to remove dust from the clothes. When the robot finishes removing the dust from the entire clothes, it moves on to the next task of removing the dust from the brush, which is described in section 2.2.
The procedure for removing dust of clothes is explained in detail using the illustration in Fig. 3. As shown in Fig. 3(a) and (b), when the robot starts, it first brings the brush to the top of the clothes. As shown in Fig. 3(c), when the brush reaches the top, it holds the clothes and moves down the brush for remove the dust from the clothes. Then, as shown in Fig. 3(d), widen the space between the brushes, extend the brush and lift up it to the top of the clothes. As shown in Figs. 3(e) and (f), the above operation is repeated, and when the dust removal operation of the entire clothes is completed, the space between the two brushes is widened and the operation is terminated by shrinking the brushes to the initial position.
The mechanism of each axis is shown in the sections of 2.1.1~2.1.3.

Axis to hold clothes
In order to remove dust from clothes, it is necessary to adhere the brush to the clothes and fix the clothes. In this study, we have developed a system that simultaneously removes dust from both sides of clothes by holding the garment between two brushes. The illustration below shows the mechanism used to perform the above operations. A motor and a wire are attached as shown in Fig. 4, and the shaft is moved to the left and right to hold the clothes.

Axis to move the brush up and down
The brush needs to be moved up and down in order to collect the dust on the clothes. In the past development of this robot, a distance sensor was used for this axis, but this was changed to control by photo interrupter for stability. The mechanism to move the shaft up and down is explained in the following illustration. To move the shaft up and down, a motor and wires are attached as shown in Fig. 5(a). In addition, photo interrupters are attached at the top and bottom of the movable range and at the middle of the range as shown in Fig. 5(b) to control the state of the axis.

Axis to extend the brush
In order to remove dust from the entire clothes, the brush needs to be extended several times over the width of the clothes. The mechanism to perform the above operation is explained in the following illustration. To extend the shaft, a motor and wires are attached as shown in Fig. 6(a). In addition, the sensor shown in Fig. 6(b) is attached to control

The operation of removing dust of brushes
The dust on the brushes is removed using the movements of the three axes described in section 2.1 and the additionally installed brushes.
When the removal of dust from the clothes is completed, the space between the two brushes is widened and the brush is contracted to the shortest point. At this time, the brush is placed at the bottom of the robot's main body as shown in section 2.1.2. The dust on the inside of the brush for dusting clothes is removed by the servo motor and two new brushes as shown in Fig. 7. At this time, the space between the two brushes for dusting clothes should be additionally widened to prevent collision between the clothes brush and the brushes brush for brushes. The brushes for removing dust of brush are initially pointed toward the robot body, and when the brushes that have finished removing dust on the clothes are placed in the area to be removed dust, the servo motors are rotated to remove dust of the clothes brushes. Next, the cleaned brush for dusting clothes is lifted up and turn the direction of brush for removing dust of brush back toward the robot's main body. In order to improve the efficiency of the operation, the photo interrupter is placed at a height where the clothes brush and brushes brush do not collide, and is lifted to that position. For the purpose of this paper, this position will be used as the middle position. When the direction of brushes brush is turned back, it places the clothes brush at the bottom. The robot's main body stops moving until the next clothes is placed in front of the robot's main body.

Robot of prototype
In this section, we describe the robot of prototype that realized the robot described in Chapter 2. Figure 8 shows the overall view of the prototype. The user hangs clothes on the rotating hanger rack on the right. The height of the hanger rack is about 1200 (mm). The robot's main body on the left side is about 740W × 495D × 1360H (mm), and the arm with the brush (Kyowa Kogyo Co., Ltd., MUGENBRUSH) for removing dust from clothes protrudes 380~830 (mm). At the bottom of the robot body is a mechanism for removing dust of the brushes, using the same brushes as above. Details of the system for removing dust of clothes and brushes described in Chapter 2 are shown in section 3.1~3.2.

The operation of removing dust of clothes
The robot developed in this paper realizes the removal of dust from entire clothes by controlling the three axes   Figure 9 shows the axis that holds the clothes of the prototype. As shown in Fig. 9, only one of the brushes is driven. The two drive units are referred to as drive unit 1 in Fig. 9(a) and drive unit 2 in Fig. 9(b), respectively. Two drive units are driven simultaneously to pinch the clothes. The brushes are driven up to 160 mm in the pinching direction. This motion is achieved by winding the wire using a motor (TAMIYA, 4-Speed Worm Gearbox H.E.) and a pulley. The motor is driven by a 5(V) DC power supply, and the drive direction is controlled by a motor driver (Toshiba, TA7291P). Use Arduino to control the state of the axis. Figure 10 shows the axis that moves the brush up and down in the prototype. Fig. 11 shows a view of the arm with the brush attached from above. As shown in Fig. 11, the arms are called Arm 1 and Arm 2, respectively. As shown in Figs. 10 and 11, arm 1 and arm 2 are driven up and down simultaneously to move the brush up and down. The brushes are driven up and down a maximum of 520 (mm). This movement is performed by using a motor (TAMIYA, AO-8037 Geared Motor 540K300) and wires. The motor operates using a 12(V) DC power supply and winds the wire with a pipe. The motor driver (Pololu, VNH3SP30) is used to control the drive direction. In addition, photo interrupters were installed at the top, middle, and bottom of the movable range in each of the two drives. The photo interrupter we created is shown in Fig. 12. As shown in Fig. 12, a partition that blocks the light of the LED was installed in the mechanism of the shaft that extends the two brushes. A photodiode (Hamamatsu Photonics, S2506-02) was used as the photo interrupter. Figure 13 shows the axis for extending the brush of the prototype. Distinguish the arm to be driven as in section 3.1.2. The brushes drive a maximum of 450 (mm). This movement is realized by winding the wire with a motor (TAMIYA, 4-Speed Worm Gearbox H.E.) and pulleys. The motor is driven by a 5(V) DC power supply, and the driving method is controlled by a motor driver (Toshiba, TA7291P). The axis to be extended can be seen by the distance sensor (Sharp, GP2Y0A21YK0F), and the distance to extend the brush can be controlled by the Arduino. Figure 14 shows the mechanism for dusting the brushes of the prototype. As shown in Fig. 14, two brushes are installed to remove dust from brushes, and each brush is controlled by a servo motor (GWS, S666 N).

Experiment
In this paper, we have developed a robot that can automatically remove dust from multiple pieces of clothes. The robot removes dust from the entire clothes by repeatedly controlling three axes: the axis that holds the clothes, the axis that moves the brush up and down, and the axis that extends the brush. The axis that moves the brush up and down is also used to clean the brush. Using a rotating hanger rack and image processing by Kinect, we have realized that the system works on multiple pieces of clothes. After verifying the operation of the control for removing dust of clothes and

The operation of removing dust of clothes
The robot removes dust from the entire clothes by repeatedly controlling three axes: the axis that holds the clothes, the axis that moves the brush up and down, and the axis that extends the brush. The operation of each of these three axes was verified.
The experiments of the three axes are described in sections 4.1.1~4.1.3.

Axis to hold clothes
The axis to hold clothes described in section 3.1.1, the time taken to move the arm from one end of the maximum range of motion to the other was 4.5 seconds for the holding  motion and about 4.0 seconds for the opening motion between the two arms. To account for the error, we moved the actuator in the pinching direction for 5.5 seconds in the holding motion and about 5.0 seconds in the opening motion between the two arms. For the pinching motion, the drive was operated for 5.5 seconds, and then the drive 2 was moved to the open direction for 1.0 second, so that the brushes pinched the clothes more strongly.

Axis to move the brush up and down
A hanger of 400W × 210H (mm) was used for the experiment. When a hanger is placed on a hanger rack, the top of the clothes is assumed to be just below the hanger. We assumed that the moving part needed to be moved within the range of 470-940 (mm) from the ground in order to remove dust from the top to the bottom of the clothes. This range was defined as the range of motion. The top of the range was set at 940 (mm) and the bottom at 470 (mm), and photo interrupters were placed at these positions.
When the brush is raised to the top of its range of motion, the drive on the respective arm side shown in Figs. 10 and 11 is activated. The motor was driven until the output of the photodiode of the two installed photo interrupters went LOW. When the output went low on photo interrupter of either arm side, only the drive unit that had not reached the top was activated. The brushes were controlled in the same way as above when they were lowered to the bottom.

Axis to extend the brush
In the axis to extend the brush, 50 averages were taken in order to reduce the sensor error. The width of the brush used was 150 (mm) and the width of the hanger was 400 (mm) from section 4.1.2. The initial position was assumed to be the state in which the tips of the two brushes were aligned without extending the arm. Dust is removed once at the initial position, and the dust is removed from the entire clothes by extending the arm twice to remove dust. Table 1 shows the position of the arm and the output voltage. The position of the arm was based on the distance from the sensor to arm 1.
The arm was moved from the initial position to position 2 using the values in Table 1. After the arm reached position 2, it was returned to the initial position.

The operation of removing dust of brushes
It was 690 (mm) from the ground, where the mechanism for dusting the brushes and the brushes for dusting the clothes did not collide. As described in section 2.2, the above height from the ground is defined as the middle position of the axis along which the brush is moved up and down.
Firstly, a mechanism to move the brushes up and down was installed at the top 940 (mm), with servomotor 1 at an angle of 0° and servomotor 2 at 180°. Next, the between arms of the axis to hold the clothes was opened. In order to avoid collisions between the clothes brush and the brushes brush, after 5.0 seconds of operation, the drive 2 was moved in the direction of the pinch for 1.0 second to create a wider space between the brushes. Move the clothes dusting brush to the bottom 470 (mm), rotate servo motor 1 to 180° and servo motor 2 to 0° position, and rotate the brush by 180° respectively to remove the dust from the clothes dusting brush.
An experiment was carried out to remove dust from clothes dusting brush by applying enough dust to the clothes dusting brush. Figures 15 and 16 show the brushes before and after the removing dust. From Figs. 15 and 16, it was confirmed that the dust on the brush was removed as a result of the experiment.

Check the entire robot
An experiment was carried out to remove dust from clothes hung on a rotating hanger rack using a prototype machine. The control of the hanger racks was carried out in the way shown in previous papers (12) . Dust was collected on a pair of short pants and applied evenly to the shorts for the experiment.  The operation of the prototype during the experiment is shown in Fig. 17. First, the hanger rack was rotated as shown in Fig. 17(a) and (b), and the short pants were placed so that they could be hold by the brushes of the robot body. Once the shorts were in place, the brush was lifted and hold the top of the short pants and moved to the bottom to remove the dust from the clothes, as shown in Fig. 17(c) and (d). As shown in Fig. 17(e), (f), (g) and (h), the brush was extended and the above actions were repeated to remove all the dust from the entire clothes. When the removing dust of the clothes was completed, the dust on the brush was removed and the brush was cleaned as shown in Fig. 17(i) and (j). When the removing dust of the brushes was completed, the brushes were lifted to the middle of the brushes and the brushes of the removing dust mechanism were returned to their initial positions as shown in Fig. 17(k) and (l). When all the above actions were completed, the brush to dust the clothes was placed at the bottom, the robot stopped until the clothes were placed again, and the hanger rack was rotated again. The hanger rack is after one rotation, robot's operation stopped.
The results of the experiment show that, in the situation shown in Fig. 17, it took 2 minutes and 31 seconds for the robot to start dusting the clothes and to rotate the hanger rack again. Figure 18 shows the dirty clothes before the removing dust and the clothes after the removing dust with the robot. Figure 18 shows that the dust on the clothes has been removed by the robot.

Consideration
In this paper, we have developed a robot that can automatically remove dust of multiple pieces of clothing and brushes. All the user has to do is put the clothes on the hanger, press the start button on the robot, and the robot will remove the dust from the clothes. With the addition of system of removing dust of brushes, the user will not have to clean the brushes after using the robot. While the robot is running, the user can spend his time doing other things. For example, by using this robot, you can make better use of your valuable morning time for yourself instead of using it to dust your clothes.
In the future, it would be more convenient if the user could specify the time for the robot to move by using a timer, or if the Kinect could recognize the type of clothes and adjust the stopping point of the axis that moves the brush up and down, or if the strength of the axis that grips the clothes could be adjusted so that the robot could properly dust clothes of different types, sizes and materials.