KIKS 2011 Extended Team Description
Hisayoshi Hattori1, Kenji Inukai1, Yasuyuki Iwauchi1, Shota Zenji1,Shoma Mizutani1, Masato Watanabe1, Kazuaki Ito1 and Toko Sugiura1
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/2011/kiks2.htm

Abstract. This paper presents an extensive and detailed presentation of KIKS
team of RoboCup small-size league (SSL). Our robots and system are designed
under the RoboCup 2011 rules in order to participate in the RoboCup
competition held in Istanbul. The overview for robots' hardware and overall forsoftware architecture of our team is described.
Keywords: RoboCup, small-size league, motion control, artificial intelligence,
IR-sensor.

1

Introduction

Main purpose of our participation to the RoboCup world competition isconfirmation and evaluation of the results of the PBL (Project Based Learning)
experiments. The creative minds of students are educated using the robot contest heldin department of electrical and electronic engineering. For the RoboCup worldcompetition, our team has continuously participated for seven years since 2004. We
came in the top 4 in Singapore 2010. In this paper, describe the overview ofmechanical and software design of the robot.

2About KIKS

2.1 Team member-Hisayoshi Hattori (Mechanics)
1

Corresponding author: sugi@toyota-ct.ac.jp

-Yasuyuki Iwauchi (Strategy)-Shoma Mizutani (Mechanics, Team Leader)-Shota Zenji (Mechanics)-Kenji Inukai (Electronic circuit)-Masato Watanabe (Supervisor)-Kazuaki Ito (Supervisor)-Toko Sugiura (Supervisor, Financial support)3Hardware of the robot

We developed robot equipped with EC45flat-motor for driving, and joined worldcompetition held at Singapore in 2010. Moving performance improved dramatically,but we found new problems.
So, we developed new robot aims to reduce breakdown based on current robot. Also,
we attempt to improve dribble-device performance.
Our robots move using four brushless motors each other. They are used pinion gearwith 20 teeth and internal gear with 72 teeth. That is, the reduction ratio is 1:3.6. Eachrobot is equipped with three solenoids. One is for straight kick, and the rest two's arefor the chip kick. These solenoids are driven by a 200[V] chargeable capacitor.
Therefore, the robot will be able to shoot the ball at a speed of 10[m/s]. Moreover, therobot can also kick the ball to the position of 3[m] away from the robot by using thechip-kick device.
The specification of the robot is shown in Table 1. The detail is described infollowing sections.
Table 1. Specification of the 2011 robot

WeightMaterial
Driving motor
Gear ratio
Wheel diameter
Number. of solenoids
Straight kick power
Chip kick power

2011
2.3kg
Aluminum alloy
Maxon EC45 flat(30Watt)
3.6:1
56mm
Straight kick:1
Chip kick:2
Ball speed of 10m/s
3.0m away from robot

At present, we are doing the minor change of the robot of 2010 model focusing
attention on the following points.
1. Changing the motor used in Dribbling device and mechanisms.
2. Redesign of wheel unit.
3. Improvement of mounting arrangement of IR-sensor.

3.1

Improvement of dribbling device

(a)

(b)

Fig. 1 Side view of dribbling devices (CAD image), (a)2010 model and (b)2011 model.

(a)

(b)

Fig. 2 Bird-view of dribbling devices (CAD image), (a)2010 model and (b)2011 model.

Figure 1 (a) and (b) shows the side view of dribbling device of 2010 and 2011
model, respectively. In similar, bird-view of that one is shown in Fig. 2. In 2010
model, it was used REmax24-motor as the dribble device motor. It was not optimal
choice because of the requirement of that large space for diameter. In addition, thepower of the dribbling motor (Maxon RE-max24) was not enough to give rise to thestrong backspin of the ball for the back pass. So we change it to ECmax22-motor.

This motor has enough power to get strong back-spin. And the size is smaller
compared with REmax24-motor. We also changed rotational orbit of the roller itself
such as arrow shown in Fig. 1 (b) 2011 model. As the results, the quantity ofhorizontal-motion increased and it was worked better for role of the buffer material tocatch a ball. Moreover, the dribble device would be able to keep in upper of the balland in wide range of dribble bar, as the results of improvement of the height of chipkick bar and the position of IR sensor as shown in Fig. 3 and Fig. 2(b) (see in detail§3.3). The gear would not be also broken by improvement of the shock-absorbing
mechanism.
The difference of the dribble device's performance is summarized in Table 2.

(b)

(a)

Fig. 3 Dribbling range of the ball (CAD image), (a)2010 model and (b)2011 model.
Table 2 Comparison between new and previous dribble devices' characterization

Dribbling motor
PowerNew(2011)
Maxon EC-max22
25WattPrevious(2010)
Maxon RE-max24
11WattNominal speed

9820rpm

5870rpm

Nominal torqueGear ratio

22.9mNm
0.84:112.4mNm
1.31:1

Velocity of the robot for backward (cm/s)

Output power of the dribbling motor (%)

Fig. 4 Backward velocity of the robot with various parameters

To decide the optimum gear ratio for the dribbling device, we measured the fastest
backward velocity of the robot which was possible to keep holding a ball with theparameter of the output power of motor and the gear ratio.
Figure 4 shows the experimental results. It assumed 0m/s in Fig. 4, when theoverload at the motor was occurred on the experimental condition. For the verticalaxis, it shows the maximum velocity of the robot which could hold the ball. As shownin Fig. 4, the robot can move faster for backward on the condition of 70% output
power with the gear ratio of 0.84:1 and 0.7:1 than that of 1.4:1. Moreover, the outputpower range of 0.84:1 is wider than that of 0.7:1. That is, the overload is occurred
over 70% output-power in the case of 0.7:1. Thus, we decide the gear ratio to 0.84:1.
And we confirmed that the backspin chip-kick was able to achieve in this condition.

3.2

Improvements in tire unit

Fig. 5 Wheel unit of 2010 model (CAD image)Fig. 6 Wheel unit of 2011 model (CAD image)

A tire unit in 2010 is shown in Fig. 5. In EC45flat, we cannot fix directly theencoder to the motor. So, it was necessary to bend the encoder cable to assemble therobot in the case of structure shown in Fig. 5. The encoder is only fixed by adhesivetape. Thus, when the encoder cable was pulled by someone or somewhat accidents,
the encoder was often come off. Therefore, we needed to change the configuration ofthe encoder. The 2011 model is shown in Fig. 6. In this structure, since the cable may
not be pulled, the probability of coming off for the encoder will be lower. Moreover,
we can treat easily for overhaul and use more flexible cable. In addition, this unit isconstructed with the popular spacer that will be getting easily. Thus, it is very good tousing for maintenance.

3.3

Change of the position of sensor to find a ballFig. 7 Positio of IR Sensor

The sensor to find a ball for 2010 model was located in side of dribble device.
Thus, when the sensor was damaged by a strong impact such as collisions between
robots, the result caused trouble of mechanics and electrical circuits. So, we tried tochange the position to of a sensor to find a ball. As shown in Fig. 7, we set the sensor
to the position of back for dribble device. That is, the robot will recognize a ballindirectly through the detection of motion of the dribble device.
As the result, the motion-range of the dribble device would be wider. Because ofthe infrared sensor could be set up inside of the robot, the possibility of thebreakdown would be lower. Moreover, the catching-range of the dribble device would
be greatly wide.

4Electrical design of new circuit

The new electronic circuits in 2011 model consist of two main boards. They aremain control unit and peripheral control unit shown in Fig. 8, respectively. The main
control unit includes the main CPU, power supply circuit, wireless communication
module, ball detecting circuit and dribbling motor controller. The peripheral control
unit includes BLDC controller and voltage booster.

Fig. 8 Construction of circuit in the new robot

4.1

Main Control unit

We have developed new main control unit. This unit includes the circuit for
detecting a ball, power supply circuit and wireless communication module. TheSH7262 (SH-2A series of Renesas) is used for a main CPU that communicate each
PIC to the peripheral controllers, such as BLDC controller, voltage booster circuit etc.
The CPU runs 144MHz (345MIPS) and has 1MB RAM. Its performance is enough toachieve the precise control of the robot.

4.2

Wireless communication system

We have used the Digi’s XBee module for communication system between host PCand each robot. The wireless communication frequency is 2.4GHz band. The XBeemodule is able to communicate faster than conventional wireless module. It is
possible to communicate up to 115200bps. Up to now, the communication speed was
19200bps. So since we will be able to send more information to the robot, it ispossible to develop more advanced controller.

4.3

BLDC controller circuit

An each robot has four BLDC control circuits for omnidirectional mobile. The MCUof BLDC controller is dsPIC30F4012. Three phase PWM module and Quadrature
Encoder Interface for motor control in MCU are very useful for development of
BLDC controller. The motor speed of the robot is controlled by PI speed control inMCU. This circuit is also used for dribbling motor controller.

4.4

Voltage booster circuit

The DC-DC converter to boost up the voltage is used for the solenoid. The input
voltage of 16V is converted to 200V output. This chopper circuit is controlled by PIC
in each robot. In the kicking device, the output voltage of 200V is charged in 4100uF
capacitor. The time to charge up to 200V from 16V is 5 seconds.

5Improvement of strategy systemStrategy system was also improved. The architecture of new strategy system isillustrated in Fig. 9. The strategy system consists of four modules called "Situation
Analysis", "Strategy", "Formation" and "Action".

Fig. 9 Construction of strategy system

5.1

Situation Analysis moduleThis module is located at top level in strategy system. This module plays the roleof analysis about the game situation from both position of the ball and robots on thefield, and generation of the trial instruction command.
5.2

Strategy moduleThis module is located at below level of Situation Analysis module. The role ofthis module is to select the optimal next Formation module from result of analyzing.
For example, when the result of analysis is “Indirect Free Kick of Own team”, theStrategy module will select the "Indirect Kick Formation module". On the other hand,when the result of analysis is “Need to Defense”, the Strategy module will select the"Defense Formation module". Since the Strategy module has many strategy patterns,
it will be able to select the optimal Strategy module corresponding to the gamesituation.

5.3

Formation moduleThis module is located at below level of Strategy module. This module plays therole of the decision of the next Action module which should be performed by eachrobot.
5.4

Action moduleThis module is located at the bottom level in strategy system. The role of thismodule is to command the specific operations to each robot. The "Direct Shoot
Action" for instance, is command to kick a ball for the robot. Alternatively, the "WallDefense Action" means moving the robot to the position to defend the goal.

6Conclusions

We have improved the robots of SSL as well as last year. As the results, someproblems found in last year were solved and the performance of the robot wasachieved best among the recent years.
We hope that our robot will be doing the best in coming world competition. And
we are happy, if the information mentioned above is somewhat useful for other team.

References[1] Piyamate et al. Skuba 2010 Extended Team Description. In: Proceedings ofRoboCup 2010.