WorksheetsIntroduction to CPS Hardware Platforms and Layers
Total questions: 30
Worksheet time: 15mins
A Cyber-Physical System (CPS) hardware platform is described as the physical embodiment of integrating computation with physical processes. Using the self-driving car analogy, which mapping best captures how the three CPS layers interact to sense, decide, and act in the physical world?
Sensors perceive the environment; the computing unit processes data and makes decisions; actuators execute those decisions to affect the physical world.
Actuators collect data; sensors execute decisions; the computing unit transmits outputs to the physical world.
The computing unit senses the road; actuators process the data; sensors cause changes in the physical world.
Sensors and actuators both make decisions; the computing unit only holds the components together.
A CPS platform is broken into three core layers. If you are designing the information flow for a CPS, which correct directional flow aligns with the roles given for each layer?
Actuation Layer → Sensing Layer → Computation & Communication Layer
Sensing Layer (input from physical to cyber) → Computation & Communication Layer (cyber brain and nervous system) → Actuation Layer (output from cyber to physical)
Computation & Communication Layer → Actuation Layer → Sensing Layer
Sensing Layer → Actuation Layer → Computation & Communication Layer
A city plans a CPS-based streetlight system that should turn lights on at dusk without human intervention. Which sensor and reasoning best fits the requirement?
Thermistor, because dusk correlates with lower ambient temperature
Photoresistor (LDR), because light intensity decreases at dusk causing resistance change the controller can detect
Ultrasonic sensor, because it can measure the distance to approaching vehicles at dusk
Accelerometer, because the pole’s vibration increases when night winds start
A hospital’s medical CPS records blood oxygen from a pulse oximeter, but the readings are noisy. Which signal-conditioning sequence most appropriately prepares the data for the computer to process?
Amplify the signal, then convert it from digital to analog
Low-pass filter to remove high-frequency noise, amplify if needed, then perform analog-to-digital conversion (ADC) to create discrete values
Increase sensor range to capture higher maximum values, then compress to digital
Raise precision by averaging multiple ADC outputs before any filtering
A CPS needs to process camera images, run a complex AI model to identify objects, and send results over the internet. Which processing unit from the options best fits this scenario, and why?
Microcontroller (MCU) because it is a compact, low-cost single-chip computer ideal for dedicated real-time control tasks
Microprocessor (MPU) because it can run full-fledged operating systems and handle complex tasks, graphics, and networking
Programmable Logic Controller (PLC) because it is ruggedized for harsh industrial environments and excels at real-time manufacturing control
System on a Chip (SoC) because it integrates almost all computer components into a single chip for power efficiency
You must choose a processing unit for a harsh factory environment to reliably control a robotic arm that welds car parts at precise moments based on sensor data. Which option is most appropriate and what characteristic makes it suitable?
Microcontroller (MCU) due to its self-contained design with RAM and Flash for low-cost tasks
Microprocessor (MPU) due to its need for external RAM and ability to run Linux
System on a Chip (SoC) due to its miniaturization and power efficiency
Programmable Logic Controller (PLC) due to its ruggedized, industrial-grade design optimized for real-time control in harsh environments
A plant needs compact integration of computation, memory, radio communication, and sensor/actuator interfacing in a single package to minimize latency and wiring complexity. Based on the diagrams, which platform best fits this requirement?
Programmable Logic Controller (PLC) cabinet with discrete modules
System on a Chip (SoC) integrating digital blocks (CPU, RAM), analog/RF, MEMS sensors/actuators, and RF/optical communication
Standalone microcontroller board with external sensors and separate RF module
Industrial PC connected to distributed I/O racks
A CPS designer needs a simple board-to-board link between a GPS module and an Arduino. Which wired protocol from the list best fits this requirement and why?
UART/USART, because it is a simple two-wire TX/RX protocol suited for board-to-board communication
I2C, because it uses two wires and is faster than SPI for high-speed data
SPI, because it uses four wires and supports many slaves on a bus
I2C, because it is full-duplex and optimized for short-distance high-speed ADC data
In the UART diagram showing two devices labeled UART 1 and UART 2, which pins must be cross-connected to enable one-way data transfer from UART 1 to UART 2?
Tx of UART 1 to Tx of UART 2
Rx of UART 1 to Rx of UART 2
Tx of UART 1 to Rx of UART 2
Rx of UART 1 to Tx of UART 2
The data buses feeding UART 1 and UART 2 are labeled bit 0 through bit 7. What does this labeling most directly indicate about the data width entering/exiting each UART?
4-bit parallel data
8-bit parallel data
16-bit parallel data
Serial data only
If UART 2 must reply back to UART 1, which additional connection is required beyond Tx of UART 1 to Rx of UART 2?
Tx of UART 2 to Tx of UART 1
Rx of UART 2 to Rx of UART 1
Tx of UART 2 to Rx of UART 1
Ground disconnected
A design requires half-duplex communication between two UARTs using a single wire. Which modification aligns with the diagram’s full-duplex default?
Tie Tx and Rx of both UARTs to the single wire without direction control
Use one shared line with tri-state control and switch which end drives Tx
Connect Tx1→Rx2 and Tx2→Rx1 on separate lines
Short Rx1 to Rx2
Two devices communicate with UART at different voltage levels. Which component should be added between Tx and Rx lines?
Level shifter
Pull-down resistor only
Optocoupler for SPI
ADC
Which design choice supports full-duplex communication as implied by two lines between UARTs?
One bidirectional line
Two dedicated lines: Tx1→Rx2 and Tx2→Rx1
Three lines plus clock
Four lines including chip select
If the data bus width changed to 16 bits, which modification is most likely required inside the UART 1 device?
Add more Tx pins
Change Rx to analog
Update parallel interface logic to accept 16-bit words before serialization
Replace UART with I2C
Which failure mode is most probable if Tx and Rx are accidentally shorted on the same UART device?
Loopback causing unintended self-reception
Improved signal integrity
No effect
Automatic speed increase
When integrating two UARTs, what parameter must be identically configured on both ends to avoid framing errors?
Baud rate, data bits, parity, stop bits
Supply voltage
ADC resolution
PWM frequency
Observing the two Arduinos linked via colored wires, which cross-connection best matches UART practice?
Tx of left UNO to Tx of right UNO
Rx of left UNO to Rx of right UNO
Tx of left UNO to Rx of right UNO and Tx of right UNO to Rx of left UNO
Connect both Tx lines together and leave Rx unconnected
If the ground lines of the two Arduino boards are not connected, what symptom is most likely during UART communication?
Stable data transfer
Random or no reception due to missing common reference
Excessive baud rate
Automatic parity correction
Which configuration enables command-response behavior between the two Arduinos using UART?
Only Tx1→Rx2 connected
Tx1→Rx2 and Tx2→Rx1 connected with a shared ground
Only Rx pins connected
Only power pins connected
If debouncing is needed for the breadboard buttons, which strategy aligns with microcontroller interfacing best practices?
Ignore bouncing; UART fixes it
Add either hardware RC debouncing or software debouncing before sending bytes
Use SPI clock to filter noise
Tie buttons directly to Rx
If the left UNO controls an actuator via received serial commands, which I/O mode is used to drive the actuator pins?
Digital output
Analog input
Serial monitor only
ICSP programming
You need to isolate the two Arduinos while still allowing serial communication. Which component provides galvanic isolation for UART lines?
Resistor divider
Optocoupler pair for Tx/Rx
Capacitor only
Heat sink
You are designing a CPS for a large farm where battery-powered soil moisture sensors must transmit data over miles to a central gateway with minimal energy use, but the data rate can be very low. Which wireless protocol is the most appropriate choice?
Wi‑Fi
Bluetooth/BLE
Zigbee/Thread
LoRaWAN
Cellular (4G/5G)
You are designing a factory conveyor system controlled by a microcontroller (MCU) that can only output 3.3V at 50mA. The system must push heavy boxes from one belt to another using compressed air, and the MCU should be able to start/stop the pushing motion reliably. Which combination best aligns with the required actuator and interface to meet these constraints?
Use a DC motor directly connected to the MCU
Use a pneumatic piston driven by compressed air, with the MCU switching a MOSFET/relay to control the valve
Use a stepper motor controlled only by GPIO pins
Use a hydraulic cylinder directly powered from the MCU
A cyber-physical system must raise and lower a car window with precise direction control using a high‑power DC motor, while the controller provides only weak signals. Which single component is most appropriate to bridge the controller and the motor to manage speed and direction?
Transistor used as a simple switch
Motor Driver IC implementing an H‑Bridge
Solenoid actuator
LCD screen
In the smart irrigation CPS, the MCU (e.g., ESP32) uses sensor inputs and online data to decide when to water. Which option best describes a robust decision rule that minimizes unnecessary irrigation while ensuring plants receive water?
Trigger the actuator whenever soil moisture is below 30%, regardless of weather.
Trigger the actuator when soil moisture is below 30% AND it is not raining based on Wi‑Fi‑fetched weather data.
Trigger the actuator whenever the temperature exceeds 30°C.
Trigger the actuator only when the user presses a button in the smartphone app.
A CPS designer must choose between an MPU and an MCU for a robotic arm that needs to run a full operating system with GPU-accelerated vision while coordinating multiple external memory modules. Using the General vs. Specialist analogy, which processing unit is the strategically appropriate choice and why?
Microcontroller (MCU), because it is self-contained and excels at precise, low-support tasks like reading sensors and controlling motors.
Microprocessor (MPU), because it commands specialized external resources (RAM, storage, GPUs) to execute complex campaigns such as running an OS and advanced algorithms.
Microcontroller (MCU), because it minimizes power by avoiding external resources and is ideal for tasks requiring GPU acceleration.
Microprocessor (MPU), because it is self-contained and operates with minimal support for tightly timed control loops.
A battery-powered smart thermostat must check a temperature sensor every millisecond and decide whether to signal the furnace. Which microcontroller features most directly justify choosing an MCU for this task? Select the best answer.
High clock speed and external DRAM modules
Deterministic real-time operation combined with low-power all-in-one integration
Cost-effectiveness only, regardless of timing behavior
Use of a discrete CPU separated from peripherals to reduce interference
A cyber-physical system team must choose between an MCU and an MPU for a module that will: run a full-featured operating system (e.g., Linux), handle complex data analysis at high clock speeds, perform multitasking and networking, and integrate external RAM and SSD via a chipset. Which choice best fits these requirements, and why?
MCU, because it integrates memory and storage on-chip and is optimized for low power tasks.
MPU, because it supports external components via a chipset, runs full-featured OSs, and delivers high performance for complex computation.
MCU, because it consumes higher power and typically requires active cooling for complex tasks.
MPU, because it does not require external memory and storage and is designed for ultra-low-power control tasks.
