Objectives:

The objective of this project was to create a 4Speed transmission gearbox that shifts gears automatically. Hence, a prototype of the same was built by using Arduino, servo motor, etc.

Methodology:

• When the potentiometer value is greater than 50 and less than equal to 225, the Servo motor rotates at an angle of 45 degrees in total. This in turn rotates the pinion, moving the rack 0.0125 metres as discussed in the gearbox design. The shaft moves the same distance as moved by the rack due to the same lever connecting them. The 8-tooth gear on driving shaft 1 will drive the 40-tooth gear on driven shaft 1 making the gear ratio 5:1. Hence, the torque is increased 5 times and speed is reduced 5 times. This gear provides the highest torque and lowest speed. This is the first gear of the transmission.

• When the potentiometer value is greater than 225 and less than equal to 511, Servo motor rotates at an angle of 90 degrees in total. This in turn rotates the pinion moving the rack 0.025 metres as discussed in the gearbox design. The shaft moves the same distance as moved by the rack due to the same lever connecting them. The 24-tooth gear on driving shaft 2 drives the 40-tooth gear on the driven shaft making the gear ratio 1.667:1. Hence, the torque is increased 1.667 times and the speed is reduced 1.667 times. This is the second gear of the transmission.

• When the potentiometer value is greater than 511 and less than equal to 767, Servo motor rotates an angle of 135 degrees in total. This in turn rotates the pinion moving the rack 0.0375 metres as discussed in the gearbox design. The shaft moves the same distance as moved by the rack due to the same lever connecting them. The 40-tooth gear on the driving shaft 2 drives the 24-tooth gear on the driven shaft making the gear ratio 1:1.667. Hence, the torque is reduced by 1.667 times and the speed is increased by 1.667 times. This is the third gear of the transmission.

• When the potentiometer value is greater than 767 and less than equal to 1023, Servo motor rotates at an angle of 180 degrees in total. This in turn rotates the pinion moving the rack 0.05 metres as discussed in the gearbox design. The shaft moves the same distance as moved by the rack due to the same lever connecting them. The 40-tooth gear on driving shaft 1 drives 8 tooth gear on driven shaft 1 making the gear ratio 1:5. Hence, the torque is reduced 5 times and speed is increased 5 times. This gear provides the lowest torque and the highest speed. This is the fourth gear of the transmission. The gear on driven shaft 1 will drive the respective gears on the output shaft as per the distance moved by the driven shaft 1 and thus respective gears will be given as output.

 

 

 

 

 

 

 

 

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Gearbox layout

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Methodology Framework

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