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Bumper sensor using GPIO - Robot control with bumper detection


1. Start "SPL script editor for MSRDS" and add SPL simulation script
  1. Add script on the editor as follows.

       
    MFEmulator    emul1
	/TargetEmulator:SPLMFConsoleEmulator
	/Procedure_I2CWrite:proc_i2c_write

StartSimulationEngine  "SimState/basicenv4.xml"

AddDifferentialDriveEntity    base1

AddBumperEntity    bumper1
	/ParentEntity:base1
	/Procedure_SensorNotify:proc_bumper

FlushScript  

Procedure  proc_bumper
	
	if (value.HardwareIdentifier == 0)
		emul1.SetGPIO("port5", value.Pressed)
	else if (value.HardwareIdentifier == 1)
		emul1.SetGPIO("port6", value.Pressed)

End

Procedure  proc_i2c_write
	
	if (value.Id == "i2c1")
	{
		command_type = value.ReceivedBytes[0]
		
		if (command_type == 1)
		{		
			distance = value.ReceivedBytes[1]
			power = value.ReceivedBytes[2]
	
			power = power - 100

			distance = Util.ToDouble(distance / 10.0)
			power = Util.ToDouble(power / 100.0)

			print "Distance -> " + distance.ToString() + " m / Power -> " + power.ToString()
			
			base1.GoTo(distance, power)
		}
		else if (command_type == 2)
		{		
			degrees = value.ReceivedBytes[1]
			power = value.ReceivedBytes[2]
	
			degrees = degrees - 100
			power = power - 100

			degrees = Util.ToDouble(degrees)
			power = Util.ToDouble(power / 100.0)

			print "Degrees -> " + degrees.ToString() + " / Power -> " + power.ToString()
			
			base1.Turn(degrees, power)
		}
		else if (command_type == 4)
		{		
			left_power = value.ReceivedBytes[1]
			right_power = value.ReceivedBytes[2]
	
			left_power = left_power - 100
			right_power = right_power - 100

			left_power = Util.ToDouble(left_power / 100.0)
			right_power = Util.ToDouble(right_power / 100.0)

			print "Left -> " + left_power.ToString() + " / Right -> " + right_power.ToString()
			
			base1.Go(left_power, right_power)
		}
	}

End
    		  


  2. Save script.

  3. Press "F5" key or click "Run" icon.



2. Add interrupt port and reaction logic for the bumper event
  1. Clear editor box of MF application.

  2. Add below script on the editor box of MF application.



       
    I2CDevice    i2c1
	/Address:58
	/ClockRateKhz:100

buff1 = Util.CreateArrayByte(3)

//go forwards
buff1[0] = 4
buff1[1] = 120	//0.2
buff1[2] = 120	//0.2

i2c1.Write(buff1)


//for front bumper
InterruptPort    port5
	/Pin:5
	/GlitchFilter:false
	/ResistorMode:PullDown
	/InterruptMode:InterruptEdgeBoth
	/Procedure_OnInterrupt:proc_port5

//for rear bumper
InterruptPort    port6
	/Pin:6
	/GlitchFilter:false
	/ResistorMode:PullDown
	/InterruptMode:InterruptEdgeBoth
	/Procedure_OnInterrupt:proc_port6
	
	
procedure proc_port5

	if (value.State)
	{
		print "fornt bumper touched"
		
		buff1[0] = 4
		buff1[1] = 80	//-0.2
		buff1[2] = 80	//-0.2

		i2c1.Write(buff1)
	}	

end

procedure proc_port6

	if (value.State)
	{
		print "rear bumper touched"
		
		buff1[0] = 4
		buff1[1] = 120	//0.2
		buff1[2] = 120	//0.2

		i2c1.Write(buff1)
	}	

end
    		  


  3. Click "Send to MF Application" button

  4. You can see a mobile robot repeat going forwards and backwards whenever bumper is touched.





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