EML 2023 – Motor Control Lecture 2 – Motor

EML 2023 Department of Mechanical and Aerospace Engineering Let’s answer 3 questions. 1.How is the motor held in place and how is it connected to the shaft that it is to rotate? 2.How does the encoder work and how is it physically connected to the motor? 3.How do the DAQ and motor driver work? 2 Motor Driver desired position current Computer and DAQ Motor analog speed signal digital direction signal Encoder sensed actual position

EML 2023 Department of Mechanical and Aerospace Engineering DC Motor a typical DC motor can rotate at a top speed of 2600 rpm (43⅓ rev/sec) gearing is used which slows the speed of the output shaft, but increases the torque gear train worm gear drive epicyclic gear train 3

worm gear drive 4 epicyclic gear train gear train

EML 2023 Department of Mechanical and Aerospace Engineering Typical Speed vs. Torque Curve 5 Rotational Speed, rad/sec Torque, lb-ft Stall Torque No-load Speed Optimum operating range Design tip: DC motors usually operator at 10-30% of their stall torque. Motors that are subjected continuously to higher loads are more prone to mechanical failure or heat-related degradation.

EML 2023 Department of Mechanical and Aerospace Engineering Buehler DC Motor 6 10 mm 6 21 mm M4 – 0.7 mm threads

EML 2023 Department of Mechanical and Aerospace Engineering Denso DC Motor 7

EML 2023 Department of Mechanical and Aerospace Engineering How does the computer control the motor? control the current (via the voltage) 8

EML 2023 Department of Mechanical and Aerospace Engineering Denso DC Motor how is the motor connected to ground? how is the motor connected to the steering shaft? 9

EML 2023 Department of Mechanical and Aerospace Engineering Connecting the Motor to Ground 10 M6 – 1mm pitch # Denso Buehler

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EML 2023 Department of Mechanical and Aerospace Engineering Denso DC Motor 13

EML 2023 Department of Mechanical and Aerospace Engineering Buehler DC Motor 14

EML 2023 Department of Mechanical and Aerospace Engineering Let’s answer 3 questions. 1.How is the motor held in place and how is it connected to the shaft that it is to rotate? 2.How does the encoder work and how is it physically connected to the motor? 3.How do the DAQ and motor driver work? 15 Motor Driver desired position current Computer and DAQ Motor analog speed signal digital direction signal Encoder sensed actual position