
Portable Uploadable Problem Set 3
For Questions 2,3,4 &5 Please refer to Brainware 7
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Question 1:
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For design of bearings, rails and actuator, please refer Brainware 7
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Slider and Actuator Preload:
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Lead Screw Life and Loads:​
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The NEMA 17 motor has a rated power of 4.2W and a rated torque of 0.45Nm. Using the Leadscrew Design spreadsheet, I was surprised to see that my linear speed is only 3mm/s for the 2mm lead that I calculated earlier.​ My original prediction using velocity = Motor Power/ Load yielded 10mm/s. The losses due to thrust bearing as well as inefficiencies in raising and lowering the table are extremely important! I increased my lead to 4mm as was able to achieve a linear speed of 5mm/s for the NEMA 17 motor. However the required torque is marginally higher than the torque of the motor.
