Week - 4

Aim:

    To Implement control logic of a 'Washing Machine' Using Stateflow as per given Sequence.

Make a Simulink chart for the 'Gear Shift' logic as per given conditions.

Objective:

    In Simulink, Implement the Control logic of a Washing Machine using StateFlow as per given input conditions. Create a model and operate the model logic system and Display the Output of the results by using Lamp Indicator.

Create a model for Gear Shifting Logic as per given Conditions.Give the Speed input While Simulation is running and Display the Gear Number.

Explanation:

Study 1:

State Flow:

Stateflow provides a graphical language that includes state transition diagrams, flow charts, state transition tables, and truth tables. You can use Stateflow to describe how MATLAB^® algorithms and Simulink^® models react to input signals, events, and time-based conditions. 

Stateflow enables you to design and develop supervisory control, task scheduling, fault management, communication protocols, user interfaces, and hybrid systems. 

With Stateflow, you model combinatorial and sequential decision logic that can be simulated as a block within a Simulink model or executed as an object in MATLAB. Graphical animation enables you to analyze and debug your logic while it is executing. Edit-time and run-time checks ensure design consistency and completeness before implementation

Control Logic:

Control Logic is model system logic using state machines, Flowchart and Truth tables.

Explanation for Control Logic of a washing Machine using State Flow: 

State Flow is a Simulink tool to implement the state machine. Here model system logic of a Washing Machine using State flow has been done.

Step1:

create a chart and enter the given input conditions.

Give 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 process have completed turn on the Finished LED

Step2:

After entering the input conditions in the chart, Go to Symbols pane and assign the given variable.

Step3:

Give the input values for turning on or off for the Power Supply and Water Supply.

Condition:

• if value=1, Power and Water Supply will turn On.
• if value=1, Power and Water Supply will turn Off.

Step4:

Use 'display' block and 'Lamp' indicator to display the results. 

Output:

Study-1:

Control Logic of a Washing Machine using State flow has been implemented.

Case-1:

If the Power Source =0, Power Supply is not available and System will not activate.

Case-2:

If the Power Source=1 and Water Source=0, then Power Supply will turn on and Water Supply will not be available and so system will not activate.

Case-3:

If the Power Source =1 and Water Source=1, then Power Supply will turn on and Water Supply will be available and so system will activate and after all Process completed end lamp will turn on.

                                                        GEAR SHIFTING MECHANISM

Mechanical devices that enable the driver to engage gears in Such a way as to obtain the desired transmission ratio are called Shifting Mechanisms.

Explanation for Gear Shifting Mechanism Using Simulink:

Step1:

Create a chart and enter the given conditions for gear Shifting.

Given Conditions:

  Speed Range(kmph)                Gear 

              0 to 15                         1

             16 to 25                        2

             26 to 40                        3

             41 to 60                        4

             Above 61                       5 

Step2:

After entering the input conditions in the chart, Go to Symbols pane and assign the given variable.

Step3:

Connect the 'Slider Gain' to vary the speed while simulation is running.

Step4:

Create Constant and giving value 1 and 0 for turning on and off.

Step5:

Create 'Lamp' to Indicate the Power is on or Off.

Step6:

Use 'display' block to display the Gear Position.

Study-2:

Gear Shifting logic has been created and by using 'Slider Gain' block, to vary the Speed while the Simulation.

Case-1:

If the key =0, then the power will turn off, Lamp indicate the Red Colour and Gear Shifting Mechanism will not activate.

Case-2:

If the key =1, then the power will turn on, Lamp indicate the Green Colour and Gear Shifting Mechanism will activate.

Case-3:

• By varying the speed(Parameter) in the Speedometer (Slider Gain), Gear position will change according to the given Condition.
• Giving speed = 30Km/hr in the Speedometer, if the Speed is between 25Km/hr - 40Km/hr 3rd Gear will activate as per the given condition. Gear Position is displayed below in the Simulink Model. 
• Like wise changing the speed in the Speedometer according to the given condition, Gear Position will Change.

Speed Range(kmph)                  Gear 

              0 to 15                         1

Speed Range(kmph)                Gear 

             16 to 25                        2

Speed Range(kmph)                 Gear 

             26 to 40                        3

Speed Range(kmph)                Gear 

             41 to 60                        4

Speed Range(kmph)                  Gear 

             Above 61                       5 

Over Speed condition: