Module 1-3 Midterm Study Guide -autoandrobotics-combined

Automation Control System

A system capable of controlling a process with minimal human assistance, initiating, adjusting, measuring variables, and stopping the process to achieve the desired output.

Mechatronics

The integration of mechanical engineering with electronics, electrical circuits, control, and software engineering. Industrial Automation:Using technology to accomplish tasks with minimal human intervention. Robotics:The use of specialized robots in industrial settings for automation.

Indusrtial Automation

Using technology to achieve tasks with minimal human intervention

Industrial Robotics

Use of specialized robots in manufacturing and other industrial settings

LabVIEW

Laboratory Virtual Instrument Engineering Workbench, a graphical programming environment for data acquisition, instrument control, and industrial automation.

Features of LabVIEW 2020

Graphical Programming, Rapid Prototyping and Development, Hardware Support, and Advanced Data Visualization and Analysis

LabVIEW programs-subroutines

Virtual Instruments (VIs) in LabVIEW that are modular programming units designed to execute specific tasks or algorithms.

Components of LabVIEW

Front Panel (user interface), Block Diagram (graphical code), Connector Pane (interface for connecting VIs), with additional elements like Icons, Controls Palette, Tools Palette, Project Explorer, etc.

LINX

An open-source LabVIEW add-on for interfacing with microcontrollers and single-board computers, simplifying connections to platforms like Arduino and Raspberry Pi for data acquisition and device control.

LINX Capabilities

Use built in sensors VI for immediate data acquisition

Access a wide range of device capabilities

Ideal for prototyping and educational purposes

Sensor

Devices that detect and respond to changes in physical stimuli, such as heat, light, motion, pressure, or moisture. They convert these changes into usable output for measurement, monitoring, or control purposes

Transducer

A device that converts one form of energy into another, facilitating communication between physical and electronic systems. Examples include thermocouples for temperature, piezoelectric sensors for pressure, and microphones for sound. Transducers can be categorized as sensors (converting physical quantities to electrical output) or actuators (converting electrical input to physical output).

Ampere’s Law

States that the magnetic field around a current-carrying conductor is proportional to the current and encircles the conductor. It helps understand the magnetic field produced by current flow, crucial in designing electric motors, transformers, and sensors. In mechatronics, it aids in predicting the strength and direction of magnetic fields generated by current in devices.

Faraday’s Law of Induction

Asserts that a change in the magnetic environment of a wire coil induces an electromotive force (emf) in the coil, generating a current if the circuit is closed. Lenz’s Law ensures that the induced current opposes the change in magnetic flux, crucial in energy transfer in transformers and power generation in electric generators.

Some factors in choosing a sensor

Environmental Factors, Economic Factors and Sensor Characteristics

Environmental Factors

External conditions that impact the operation of a sensor, such as temperature, humidity, and exposure to chemicals.

Economic Factors

Considerations related to the cost, availability, maintenance expenses, and lifetime of a sensor.

Sensor Characteristics

Technical specifications of a sensor including accuracy, range, resolution, response time, and stability.

Two types of Automation System Inputs

Digital and Analog Inputs

Digital Inputs (DI)

Binary signals represented as "ON" or "OFF" used in automation systems.

Analog Inputs (AI)

Signals that vary continuously over a range and can represent multiple values in automation systems.

Push-button

A momentary or non-latching switch that controls aspects of a machine or process.

Biased Switches (momentary)

Buttons that automatically return to their starting position after being pressed due to an internal spring mechanism

Un-Biased buttons (latching)

These push buttons remain in their activated state after being pressed and released. They do not have a mechanism that automatically returns them to their initial position.

Normally Open (NO)

The contacts are open when the button is not pressed

Normally Closed (NC)

The contacts are closed when the button is not pressed

NEMA

National Electrical Manufacturers Association, an organization that develops standards for electrical equipment.

Momentary Contact Push-Button

Single Circuit

Double Circuit

Mushroom Head

Wobble Stick

Single Circuit

NO (Normally Open): Activates a circuit when pressed. NC (Normally Closed): Deactivates a circuit when pressed.

Double Circuit

NO (Normally Open): Activates two circuits when pressed.

NC (Normally Closed): Deactivates two circuits when pressed.

Mushroom Head

Indicates an emergency stop button

Wobble stick

Represents a joystick-like actuator for multidirectional control

Maintained Contact Push Buttons

Two Single Circuits

One Double Circuit

Two Single Circuits

Two separate buttons that maintain their respective circuit states.

One Double Circuits

A single button that maintains two circuit states

Illuminated Push Bittons

Double Circuit with Illumination: Indicates a push-button that lights up when its double circuit is engaged.

Limit Switches

Normally Open (NO): Contacts close, current flows when activated.

Held Closed: Contacts stay closed, maintaining current flow until released.

Normally Closed (NC): Contacts open, current stops when activated.

Held Open: Contact stays open, interrupting current flow until released.

Foot Switches

NO (Normally Open): Contacts close, activates circuit on press.

NC (Normally Closed): Contacts open, deactivates circuit on press.

Pressure and Vacuum Switches

NO (Normally Open): Contacts close, engages circuit when pressed.

NC (Normally Closed): Contacts open, disengages circuit when pressed.

Liquid Level Switches

NO (Normally Open): Contacts close, triggers on high level.

NC (Normally Closed): Contacts open, resets on high level.

Temperature-Actuated Switches

NO (Normally Open): Contacts close, circuit completes with heat increase.

NC (Normally Closed): Contacts open, circuit breaks with heat increase.

Flow Switches

NO (Normally Open): Contacts close, engages circuit with flow. o NC (Normally Closed): Contacts open, disengages circuit with flow

Linear Variable Differential Transformer (LVDT)

A transducer that measures linear displacement by converting mechanical motion into an electrical signal through electromagnetic coupling.

Strain Gauge

Measures deformation by changing its electrical resistance in response to applied strain, allowing for precise detection of strain through voltage changes.

Wheatstone Bridge

A circuit used for precise resistance measurements, where a strain gauge can be incorporated to measure small changes in resistance accurately.

Galvanometer

Device that meatures small electric currents

RTD

Resistance Temperature Detector is a sensor that measures temperature based on the change in electrical resistance of metals like platinum with temperature variations.

Thermocouple

A temperature sensor consisting of two different metal wires joined at one end to measure temperature based on the voltage produced due to the thermoelectric effect when the junction experiences a temperature change.

Wheatstone Bridge Circuit

A circuit used with RTDs to enhance accuracy by compensating for lead wire resistance and other sources of error in resistance measurement.

Seebeck Effect

The principle behind thermocouples where a voltage is generated when two different conductors form a circuit and have junctions at different temperatures.

Cold Junction Compensation (CJC)

A technique used to adjust for the temperature of the cold junction in thermocouples to ensure accurate temperature measurements.

Accelerometer

A sensor that measures acceleration forces along its sensitive axes, designed to be insensitive to motion or forces perpendicular to those axes.

Sensitivity to Axes

The sensitivity of an accelerometer is aligned with one or more axes, labeled as the X, Y, and Z axes. Each axis corresponds to a direction along which the accelerometer can measure acceleration.

Uniaxial Accelerometer

An accelerometer designed to measure acceleration in one axis.

Biaxial Accelerometer

An accelerometer designed to measure acceleration in two axes.

Triaxial Accelerometer

An accelerometer designed to measure acceleration in three axes.

Orthogonal Insensitivity

In accelerometers, orthogonal insensitivity means the sensor is designed to be insensitive to acceleration forces not aligned with its sensitive axis or axes.

Light Sensors

Devices that detect light intensity and are composed of photoconductive materials like photoresistors, photodiodes, or phototransistors.

Photoresistor (LDR)

A light-sensitive variable resistor where resistance decreases as light intensity increases.

Photodiodes

Semiconductor devices that convert light into current.

Phototransistors

Semiconductor devices similar to photodiodes but provide greater sensitivity and amplification of the electrical signal.

Magnetic Sensors

Devices that convert changes in magnetic fields into electrical signals to measure parameters like current, speed, position, and displacement.

Hall Effect Sensor

A transducer that uses Hall elements to produce a voltage directly proportional to the strength of a magnetic field perpendicular to the flow of electric current.

Hall Effect Principle

The principle where a voltage (Hall voltage) is generated when a magnetic field is applied perpendicular to the flow of electric current in a conductor.

Common Applications of Hall Effect Sensors

Proximity sensing, positioning, speed detection, current sensing, brushless DC electric motors, and industrial automation.

Photogates

Sensors that detect the presence of an object by measuring interruptions in an infrared light beam, used in counting applications and determining the period of periodic motion.

Infrared Beam

A beam of light emitted by the transmitter of a photogate that is temporarily blocked when an object passes through the U-shaped gap.

Vernier Photogate

A device engineered for precise timing of interruptions of an infrared beam by objects passing through, enabling accurate measurement of time intervals.

Differential Pressure Sensors

Devices that measure the difference in pressure between two points, crucial for applications requiring monitoring pressure gradients.

Absolute Pressure Sensors

Devices that measure pressure relative to a perfect vacuum, essential for applications needing absolute pressure values.

Pressure Sensors

Devices that measure pressure or force exerted by fluids or gases, crucial for systems interacting with fluids or gases.

Strain Gauge

A type of pressure sensor where deformation of a diaphragm changes electrical resistance to indicate pressure.

Piezoresistive

A type of pressure sensor where mechanical stress alters resistive properties of a material to measure pressure.

MEMS (Microelectromechanical Systems)

Pressure sensors utilizing microfabricated diaphragms and sensors to detect pressure through minute physical changes.

Signal Conditioning

The process of modifying an analog signal to make it compatible with the next processing stage, involving converting, scaling, or filtering the signal.

Operational Amplifiers (Op-amps)

Components used in the signal conditioning stage of mechatronics applications to amplify sensor signals for processing by an ADC and a microcontroller.

Signal Conditioning

The process of converting conditioned sensor signals into digital form, interpreting these signals with a microcontroller, and performing necessary computations and control actions to make decisions based on sensor inputs and execute appropriate responses.

Op-Amps

Versatile electronic components with high gain used for amplifying signals to a level readable by analog-to-digital converters and microcontrollers, improving signal quality by enhancing the signal-to-noise ratio, and performing various filtering and signal conditioning tasks.

Passive Circuits

Circuits containing passive components like resistors, capacitors, and inductors that do not require an external power source to operate and cannot amplify a signal.

Active Circuits

Circuits containing active components like transistors or operational amplifiers that require an external power source to operate and can amplify or switch signals.

Bridge Circuit

An electrical circuit used to measure resistance, impedance, capacitance, or other electrical quantities by balancing two legs of a bridge circuit, producing a measurable voltage when an imbalance occurs due to a change in the measured quantity.

Gain

A measure of the amplification level of an electronic signal, represented as the ratio of output signal power to input signal power, important in various applications from audio amplification to signal processing in sensors and communication systems.

Common Mode Rejection Ratio (CMRR)

A measure of an amplifier's ability to reject common-mode signal inputs while amplifying differential-mode signals, crucial for accurate signal processing.

Instrumentation Amplifier

A high-precision circuit amplifying the difference between two input voltages using buffer amplifiers and a differential amplifier, with features like precise gain adjustment and high CMRR.

Quantization

The process of mapping a large set of input values to a smaller set, usually as part of digitizing analog signals. In digital signal processing, it involves converting a continuous range of values into a finite range of discrete levels.

Sampling Theorem

The Nyquist-Shannon sampling theorem stating that a continuous signal can be completely represented and reconstructed from its samples if the sampling frequency is greater than twice the highest frequency of the signal.

Nyquist Rate

The minimum sampling rate required for perfect reconstruction of a signal, which is twice the highest frequency component present in the signal.

SAR ADC

Successive Approximation Register Analog-to-Digital Converter, a device that converts analog signals into digital form by comparing each binary bit of the digital output to the analog input signal in successive steps.

Range

The span between the minimum and maximum values a sensor or instrument can accurately measure.

Accuracy

The degree to which the measured value conforms to the correct value or a standard

Presicion

The consistency of repeated measurements, indicating the closeness of the measurements to each other

Hysteresis

The delay or lag in the response of a system to changes in the input, usually seen as a difference in the output when the input increases versus when it decreases, leading to a “dead zone.”

Resolution

The smallest change in a measurable quantity that an instrument can detect.

Systematic Errors

are consistent, directional inaccuracies that arise from known or unknown sources within the measurement process, leading to a predictable bias in the results.

Random Errors

unpredictable, non-directional variations that stem from inherently uncertain factors, causing scatter in measurement results that usually follow a Gaussian distribution

Calibration

The process of establishing the relationship between the physical measurement variable (X) and the signal variable (S) of a sensor or instrument. This is achieved by applying known physical inputs and recording the system’s response to align the measurement with standard units of reference.