The design parameter of the syringe pump are shown in Table 1. For measuring the flow rates a precision balance (Shimadzu Corporation (AUX220 model)) which has a measuring range of 220gms with a minimum display of 0.1mg and a linearity of 0.3mg is used. The repeatability of the balance is less than or equal to 0.1mg. Table 1. Parameters of Syringe Pump
Number of Steps
Pitch Length (cm)
Volume of Fluid inside the Syringe (ml)
Length of the Syringe (cm)
2.3 Control Algorithm
Fig 4 shows the flow chart of the control algorithm. The stepper motor is controlled by an 8051 microcontroller. The time delay is assigned based on the input based on the calculation shown below.
Time required for 1 rotation
Since for every rotation there is a forward movement equal to 1 pitch length of the plunger
Time required for a single Pitch length forward movement
Volume of fluid at exit in a single pitch length movement
So the flow rate