System Design 2 Final Test

Goodluck Motherfuckers

Lecture 4: System Design II Gearboxes

Why use gearboxes?

Increase torque, decrease speed, decrease reflected inertia.

What does a gearbox provide?

Leverage.

What is backlash?

Slop or free play in gears.

Why are helical, bevel, and worm gears not good for servos?

Too much backlash, too much friction.

What is the benefit of tapered gears in stepper gearhead motors?

They reduce backlash.

Describe a planetary gearbox.

Consists of sun gear, planetary gears, internal gear; multiple stages available; used to reduce speed and increase torque.

What is harmonic (strainwave) gearing known for?

Zero backlash, compact, expensive, allows large reductions.

How does gear reduction affect torque and speed?

More reduction = increased torque, decreased speed.

How does gear reduction affect inertia?

Reduces load inertia reflected to motor by the square of the gear ratio.

Lecture 5: Automated Circuits II Motors

Why not use brushed motors?

They typically run at set speed and are difficult to control.

What is a stepper motor?

A brushless DC motor that rotates in steps, allowing precise open-loop control.

What is wave drive in stepper motors?

One coil active at a time; rotor completes full cycle in 4 steps.

What is full step mode?

Two coils active, higher torque, same resolution.

What is half step mode?

Alternates between one and two coils, doubles resolution.

What is microstepping?

Uses variable current to smooth motion and increase accuracy, but reduces torque.

How does stepper motor torque behave with RPM?

Torque drops quickly as RPM increases.

What is a servo motor?

Rotary actuator with feedback for precise closed-loop control.

What are common servo feedback devices?

Encoders or resolvers (absolute, incremental).

What does a PID loop do?

Controls position, velocity, acceleration, torque using proportional, integral, and derivative gains.

Lecture 6: Automated Circuits II Sensors

Why are sensors used in automation?

To communicate machine status.

What are two main types of sensor signals?

Digital (on/off) and analog (4-20mA, 0-10V).

What do inductive sensors detect?

Metallic objects using electromagnetic induction.

What do capacitive sensors detect?

Metallic and non-metallic objects by measuring dielectric property.

How do photoelectric sensors work?

Emit and receive light; detect interruptions or reflections.

How do ultrasonic sensors work?

Emit high-frequency sound waves and detect reflected signals.

What is special about Lidar sensors?

Use laser light to measure distance; enable 3D scanning.

What are magnetic field sensors?

Detect magnetic fields, e.g., Hall effect, reed switches.

What do potentiometers measure?

Position using variable resistance.

What is a magneto restrictive sensor?

Uses ultrasonic waves in a wire to detect position without contact.

What is an inclination sensor?

Measures tilt using MEMS accelerometers.

What do pressure sensors measure?

Pressure using piezoelectric or mechanical methods.

What types of temperature sensors exist?

Thermocouples, thermistors, RTDs, semiconductor-based sensors.

What do flow meters measure?

Flow rate of liquids or gases.

What are encoders used for?

Measure position (absolute or incremental).

What is an RFID sensor?

Uses radio waves for identification.

What is a 3D vision system?

Captures and processes 3D images for automation tasks.