Dice  Probablity

Nakata  Ryohei  Otani  Ryota  Sakano  Mikiyasu  

Background

We  wondered  whether  the  probability  of  each  roll  will  be  equal  to  0.16.    

Prof.  Izumori  advised  that  I  should  roll  dice  thirty-­‐thousand  Imes  to  invesIgate  dice  probability.  So  I  decided  to  make  automaIc  dice  roller.  

Commercially  Available  Dice  shaker

Fault:  Dice  come  from  wrong  place  Dice  doesn’t  always  roll  well    

Result

0.11

0.12

0.13

0.14

0.15

0.16

0.17

0.18

0.19

0.2

0.21

300 600 900

roll 1

roll 2

roll 3

roll 4

roll 5

roll 6

Self-­‐made  Dice  Roller  1

Fault：  It  isn’t  suited  for  rolling  many  dices  at  the  same  Ime.  

Result

0.14

0.15

0.16

0.17

0.18

0.19

0.2

300 600 900

roll 1

roll 2

roll 3

roll 4

roll 5

roll 6

ObservaIons  I

•  It  is  essenIal  to  roll  dice  many  more  Imes.  •  It  is  necessary  to  make  a  new  automaIc  dice  roller.

Experiment  III  Saikoron

wheel  for  dice  rotaIon ＷＥＢ  camera

CPU  board Small  direct-­‐current  motor

The  breadboard    for  electronic  circuits  

Switching  AC/AD  adaptor  

Result

0.14

0.15

0.16

0.17

0.18

0.19

1500 3000 4500 6000 7500 9000 10500

ObservaIons  II

•   

ObservaIons  II

　Thus,  it  can  be  expected  that  the  more  dots,  the  higher  the  frequency  of  rolling  that  side,  and  the  less  dots,  the  lower  the  frequency.

Assignment

•  finish  rolling  dice  30,000  Imes  and  collecIng  data.  

•  improve  Saikoron  machine  as  a  conInuous  experimental  tool.  

•  verify  the  probability  of  those  dice.  •  examine  the  variaIon  in  the  probability  aWer  changing  the  center  of  gravity  of  the  dice.  

GraItude

•  Norifumi YAMADA (Professor, Fukui University),

•  Hitoshi IZUMORI (Professor, Kanagawa University)

•  Naoki  KOBAYASHI  (IRISO  SEIMITSU  Co.,  Ltd)

Bibliography

•  "my  Arduino  work  note“(Tetsuya  Suzuki  work,  latosol  publica<on,  2013)  

•  "Arduino  will  be  begun"  (Massimo  Banzi  work,  O`REILLY  publicaIon,  2012)

Thank  you  for  listening!

PreparaIon

1.  CPU  board　　　Arduino　UNO　R3  2.  micro-­‐relay  switch　(Made  in  OMRON)　G6E-­‐134P  3.  electronic  circuits  bread  board  4.  small  DC  motor  (MabuI  motor  RE140RA)  adached  to  a  

two-­‐step  pulley  5.  dice  rotaIng  wheel 6.  Switching  AC  adapter  (1.5V　600mA)  7.  ＷＥＢ camera　　(  3.2million  pixel  web  camera  made  in  

Melco)  8.  pulley  and  rubber  ring