Motor sizing and battery sizing:

Motor selection:DC MOTOR

Density of circular wheel:2.70g/cm^3

Volume of circular wheel:1.25 cm^3

Mass of circular wheel= Density*mass

Mass of circular wheel= 2.70*1.25

Mass of circular wheel=3.375kg

Force=mass*acceleration due to gravity

force = 3.375*9.81

force=33.108N

Torque = force*radius

Torque=33.108 * 40 * 10^-3

Torque =1.32432kg-cm

Torque (final)=Torque *1.5

Torque (final)=1.32432*1.5

Torque (final)=1.98648kg-cm

Torque (final)=1.98648kg-cm =2.0kg-cm

So selected DC motor is DC Geared motor specification is =100rpm ,100RPM 12V Centre shaft DC Geared motor

one stepper motor is used for seed dispensing machine

Adapter Sizing

DC motors is used hence,

2*500=1000 mA and 12V

Factor of safety=1.2

1000*1.2= 1200 mA

Hence the adapter should be 12V and 1.5A

Stepper motor stall current = 1600 mA

Factor of safety = 1.2

stall current * FOS = 1600 * 1.2 = 1920 mA @ 5v

Hence the Adaptor of 5v and 2A is selected .