KIKS 2010 Team Description
Ryuhei Sato1, Takato Horii1, Kenji Inukai1, Shoma Mizutani1,Kosei Baba1, Masato Watanabe1, Kazuaki Ito1 and Toko Sugiura1
1
Toyota National College of Technology,
Department of Electrical and Electronic engineering,
2-1 Eisei-cho, Toyota Aichi, 471-8525, Japansugi@toyota-ct.ac.jp
URL：http://www.ee.toyota-ct.ac.jp/~masa/2010/kiks2.htm

Abstract. This paper is used to qualify as participation to the RoboCup 2010
small-size league (SSL) about team “KIKS”. Our robot is designed under theRules 2010 in order to participate in the SSL competition held in Singapore.
The overview for robots’ hardware of our team is described .
Keywords: RoboCup, small-size league, brushless DC motor, motion control,IR-sensor.

1Introduction

Main purpose of our participation to the RoboCup world competition is
confirmation and evaluation of the results of the PBL (Project Based Learning)
experiments. We have educated the creative minds of students using the robot contest
held in our department of electrical and electronic engineering. For the RoboCup
world competition, our team has participated for six years since 2004, continuously.
We came in the top 8 in Graz 2009. Thus, since the aim will be higher, furtherimprovements are also needed in this year.
Recently, most of best top teams use the brushless DC motors. But we still use
brushed one (REmax 24). If we can replace to the blushless one, the robots must havemore torques and speeds. So, now we try to replace that and also review wholemechanical design.
The main topics of developed system in 2010 are following term,･ Enhancement of the performance of dribbling and kicking devices of the robot
in SSL.
･ Evaluation of the performance of ring-wheels and chip-kick devices.
･ Development of the circuit for DC blush less motors.

2

Development of new robots

2.1

The entire structure design.

At present time, we have changed three parts.
1. Replacement to brushless DC motors (Maxon EC45flat) from brushed one(Maxon REmax24).
2. Redesign of chip-kick device.
3. Whole mechanical redesign taken into account of maintenance.
First, the motors which connect four ring-wheels were replaced to brushless motors(Maxon EC45flat). They were used pinion gear with 20 teethes and internal gear with72 teethes. That is, the reduction ratio is 1:3.6. The robot has not enough space to set
the gear box. So, we had to redesign to take account of narrow space between motor’saxis and wheel’s that as shown in Fig. 1.

Fig. 1 Ring-wheel and internal gear
Second, the chip-kick devices were redesigned. The solenoid of chip-kick device
was under a normal kick device for previous design. But the solenoid often
electrically short out because of rubbing itself against floor. Thus, we replace thesolenoid of chip-kick device on that of the normal kick device as shown in Fig. 2. As
the results, we solved the problem mentioned above. Furthermore, because of large
space between chip-kick device’s bar and solenoid, it could get more kick power due
to the principle of leverage. In addition, the redesigning brought many advantages forrobot performance, e.g., more precise pass by kicking the center of a ball.

Fig. 2 Chip-kick device
Finally, whole mechanical structures were improved taken into account themaintenance. Our robot had many problems in play because of components from a lotof hand-made parts. At present, we replaced the base-plate to thick one and also madethe dents on the plate. The wheel units and kick devises were embedded in the plate as
shown in Fig. 3. As the results, the number of screws to fix on the body were able todecrease because of the dents were worked effectively as shock-absorber against theforces from various directions. If the robot is broken, it will be fixed up easier due tothe geometric design.

Fig. 3 Whole mechanical design

2.2

Evaluation of wheel structure.

Robots could run faster than last year by replacing the motors. As the results,
robots were required high performance for ring-wheels. So, we tried to improve thering-wheel’s structure. We had tested some types of ring-wheels as shown in Fig.
4(a)-(d). The (a) is the present type which has thin single tire with every thin unit
house. The (b) type has double small tires with every unit. The (c) and (d) types havethick small tires which made normal rubber and silicone rubber tube, respectively.

(a) with single ring tires(b) with double ring tires(c) with thick rubber ring tires(d) with thick silicone rubber ring tires

Fig. 4 Various type of the wheels used for evaluation.

(a)
(b)
(c)
(d)
Fig. 5 Average time to reach to 1[m/s] from static condition for the robot

(a)

(b)

(c)

(d)

Fig. 6 Average moving speed of the robot on the same condition
The experimental results of their performance are shown in Fig. 5-Fig. 6. Figure 5
shows the average time to reach to 1[m/s] from static condition. Figure 6 shows theaverage moving speed on the same condition. Summarizing the results, the (a) typeshowed the most stable and best performance. Thus, we decided to use (a) type.

2.3

Chip-kick device structure

The chip-kick device was also tried to improve. We investigated the relation
between the length of rotation axis and angle within the limits of the space. By
determining the length R and angle θ, respectively as displayed in Fig. 7, we havemeasured a range of ball when the R and θ were changed. The result shows that arange of ball is strongly depend on the θ as shown in Fig. 8. On the other hand, the Ris shown enough to have only a few cm. Thus, we decided tentatively that the R is
25mm and the θ is 60°. A kicked ball reaches a height of approximately 600mm.
Obtained actual performance is shown in Fig. 9.

Fig. 7 Length of rotation axis R and angle θ of the chip kick device

Fig. 8 Experimental results of chip-kick device

Ball
60°

25mm

45°

Ball
Ball

~600mm25°~2000mm

Fig. 9 Specification and performance of actual chip-kick device

2.4

Dribbling device structureIn previous robot, we have used the RE-max17 motor for the dribbling devices.
But the motor did not have good enough performance for pass and shoot. So we tried
to change that motor into RE-max24. The motor’s power has increased from 4W to10W. In addition, we just changed the dribble devices. Table I shows the performanceof new dribbling device. The previous and new dribbling devices are also shown inFig. 10.
Table I. Characterizations of new and previous motor.
New(Re-max 24)
Previous(Re-max 17)
Element＼MotorPower10 Watt
4 WattDiameter of Roller~15mm~13mm
Rotation
8800rpm
3900 rpm
Frequency(Roller)(a) Previous dribbling device (CAD image)(b) New dribbling device (CAD image)(c) New dribbling device (side view)(d) New dribbling device (front view)Fig. 10 Previous and new dribbler device
2.5

Detecting device for a ball

Up to now, the IR-Sensor was only used to find a ball in our robot. So, we attached
a new another IR-Sensor to check the position of the ball, and to enhance theperformance of catching the ball. As the result, the robot came to check the difference

of the position between the ball and robot, and obtained the good performance forcatching the ball. Attached new IR-Sensor is shown in Fig. 11.

(a) IR-sensor(b) Body with IR-sensor

Fig. 11 Detecting device (IR-sensor) for a ball
2.5

Electronic circuit for brushless DC motor.

We decided to use brushless DC motor because it is becoming one of the standard
equipment of the robots among the best teams in SSL. We replaced the motor toMaxon EC 45 flat from Maxon RE-max 24. The motor is popular in the best team.
The motor’s power is more than six times compared with conventional RE-max24.
Therefore, the gear ratio could change from 8:60 to 20:72. As the result, the machine
was able to run more than 1.5 times faster than previous one.
There are two sensors in the motor. That is, the encoder and the hall sensor built inthe motor. E4P made by US DIGITAL was chosen as the encoder. Since its resolution
is 1440 pulse per revolution, it came to control easier in detail.
The Microchip dsPIC30F4012 was used for each motor’s control. The PICs wereconnected to the motor through FET drive circuit. Each PIC was commanded bySH2-7144 of Main MPU.

(a) Brushless Motor(b)Encoder

Fig. 12 Brushless motor and encoder

(a) FET circuit(b) Control circuit
Fig. 13 (a) FET circuit for motor drive unit and (b) its control circuit

3Conclusions

We have improved the robots for SSL as well as last year. The performance of ourrobot is getting high over the year. Most of devices are hand made by students. Thus,
the cost performance is very high in fact.
We hope that our robots will perform better in this coming competition than that oflast year. We will have a plan to join such competitions continuously in the future.

References
1. Touko SUGIURA, Masato WATANABE and Kazuaki ITO: Practice of Creative Education
Taken into Account the Continuous Participation to the RoboCup Small Size League andWorld Competition, Journal of Education in the Colleges of Technology, 32 (2009) 345. [inJapanese]