Project 7 - SIMULINK - Control logic - State flow

AIM  : 

1. To implement control logic of a “washing machine” using State flow as per the inputs provided in power & water supply.
2. Make a Simulink chart for the “Gear shift” logic. Give speed input while the simulation is running & display the gear number.

OBJECTIVE:

• Generate a Simulink model to Washing Machine at various states.
• Generate a Simulink model to Shift the Gear according to input speed.

SOLUTION:

The Washing Machine is a machine were many operations are done within a short time period. It performs the operations like soaking, washing, rinsing and drying the clothes w.r.t to the time programmer control which is inbuilt.

The washing machine concept is pretty simple – it agitates your clothes in a soapy suds and water to remove any dirt and stains before spinning to drain the water after the cycle. The main components of a washing machine is the drum, which fills up with water, but did you know that washing machines actually have two drums, not one? Your average washing machine is made up of: 

An inner drum. This is where you put the clothes when you’re ready to wash. You’ll notice this drum rotates a bit when you touch it and there are a lot of holes punched into the drum. These allow the water to come in and wash the clothes. 

Paddles. These are ridges that lie on the edge of the drum and help move your clothes around while being washed. 

Agitator. These are more common in top load machines and is a paddle in the middle that helps turn the clothes around in the soapy water. 

The outer drum. This is not obvious when you look inside the washer, but there is another drum that holds the water while the inner drum or agitator rotates. This part is completely water tight to prevent your machine from leaking all over the bathroom or kitchen! 

Thermostat and heating element. These control the temperature of the water and heats up the water to the specified temperature. 

Pump. This removes the water from the drum after the wash. 

Programmer. This controls the washing machine through all the steps from washing to rinsing and spin drying. 

Pipes and valves. These allow the water in and out of the washer.

State-Flow:

State-flow provides a graphical language that includes state transition diagrams, flow charts, state transition tables, and truth tables

State-flow for Washing Machine:

Input Conditions: -

If the power supply is available, the system gets activated

If the Water supply is not available, stop the process & indicate through LED

Soaking time should be 200s followed by washing time of 100s.

Then rinsing happens for next 20s & dryer runs for 50s

After all the processes have completed turn on the finished LED

Steps:

1. Create a chart in Simulink which satisfies all the above mentioned conditions.
2. Open the ‘Symbols panel’ and assign proper data. (i.e input or output).
3. Connect LED lamps to each process and set them accordingly.
4. Provide the output as a display.
5. In order to view the output we have provided display block and lamps.

Values 1 & 0 are given as input which switch ON and switch OFF the supply of power and water respectively.

State-flow for Gear Shifting:

Input Conditions: -

Speed Range (kmph) 0 to 15 - Gear 1

Speed Range (kmph) 16 to 25 - Gear 2

Speed Range (kmph) 26 to 40 - Gear 3

Speed Range (kmph) 41 to 60 - Gear 4

Above 61 (kmph) - Gear 5

Steps:

1. Create a chart in Simulink which satisfies all the above mentioned conditions.
2. Open the ‘Symbols panel’ and assign proper data. (i.e input or output).
3. Provide the output as a display and also provide a scope view the graph.

Output:

WASHING MACHINE MODEL: -

For Condition where Power=1 & Water=1

For Condition where Power=0 & Water=1  

For Condition where Power=1 & Water=0

For Condition where Power=0 & Water=0

GEAR SHIFT MODEL: -

For speed < 15 (Gear 1)

or speed < 25(Gear 2):

For speed < 40(Gear 3):

For speed < 60(Gear 4): 

For speed > 60(Gear 5):

Variation in Gear Shift:

Conclusion   –

Thus we have successfully prepared a Simulink model for an automatic Washing Machine which can perform various operations if proper input is provided by the user.

Thus we have successfully prepared a Simulink model for a gear shifting mechanism which changes the gear for different ranges of speed