Motor sizing.

* Mass of the shaft(m) = 90*10^-3 kg = 0.09

* Radius of the shaft(r) = 0.8 cm

* Co efficient of friction between nylon rod and acrylic sheet = 0.06

* Factor of safety(f) = 1.5

* Acceleration due to gravity = 9.8m/s^2 = 980cm/s^2

* FORCE(F) = W * 0.06

        = m * g * 0.06
        = 0.09 * 980 * 0.06
        = 5.292N

* TORQUE = F * f * r

         = 5.292 * 1.5 * 0.8                                     
         = 6.3504 kg.cm

Baterry sizing.

Maximum current consumed by the dc motor = 300 mA.

Baterry capacity = (Maximum current consumption) * (No. of working hours)

                 = (300)*(3)
                 =900mAH.

We need 5 dc motors ,so (5)*(900)=4500mAH.

Torque is 6.3504 kg.cm,so we need 15rpm or 30rpm dc motor.

Sl.no	Motor type	no.of motors	Torque in kg.cm	rpm	Current consumption	Voltage required
1	Dc motor	5	6.3504	15rpm or 30rpm	300mA	12v