Engineering Concepts

 Sorting Algorithm :  1. Bubble Sort Bubble Sort repeatedly swaps adjacent elements if they are in the wrong order. C code: #include <stdio.h> void bubbleSort(int arr[], int n) { for (int i = 0; i < n-1; i++) { for (int j = 0; j < n-i-1; j++) { if (arr[j] > arr[j+1]) { int temp = arr[j]; arr[j] = arr[j+1]; arr[j+1] = temp; } } } } Complexity: Best Case: O(n) (already sorted) Average Case: O(n²) Worst Case: O(n²) Space: O(1) (in-place) 2. Selection Sort Selection Sort finds the minimum element and places it at the beginning. C code: void selectionSort(int arr[], int n) {     for (int i = 0; i < n-1; i++) {         int minIndex = i;         for (int j = i+1; j < n; j++) {             if (arr[j] < arr[minIndex]) {                 minIndex ...

C:\Users\nick> ssh pi@192.168.1.5 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that a host key has just been changed. The fingerprint for the ED25519 key sent by the remote host is SHA256:5ATMhAY78GjHr6ty8ODazLE6sCoZohQSJynphxRBh3Q. Please contact your system administrator. Add correct host key in C:\\Users\\nick/.ssh/known_hosts to get rid of this message. Offending ECDSA key in C:\\Users\\nick/.ssh/known_hosts:41 Host key for 192.168.1.5 has changed and you have requested strict checking. Host key verification failed.   Solution : C:\Users\nick> ssh-keygen -R 192.168.1.5 Then run command again to connect via ssh: C:\Users\nick> ssh pi@192.168.1.5

  This error is very common with Moog controllers—even when  ping works , the  Streaming Service (SmartSDK)  may still be blocked or not running. What your error means “Controller cannot access the Moog SmartSdk Streaming Service” So: Network connectivity = (ping works) Application-level communication =  (blocked or service missing)   Step-by-step troubleshooting 1. Check Windows Firewall (MOST COMMON CAUSE) The error itself already hints this. Do this on your PC: Open  Windows Defender Firewall Go to: Allow an app through firewall Look for: Moog PC App SmartSDK / Streaming Service If not listed: Temporarily disable firewall and test: Control Panel → Windows Defender Firewall → Turn OFF   If it works → firewall is the issue  Then add exception for: Your Moog application Required ports (see below)   2. Check if SmartSDK Streaming Service is r...

Introduction The Raspberry Pi has evolved from a hobbyist’s toy into a powerful embedded computing platform. Its versatility makes it ideal for prototyping, IoT applications, robotics, and even industrial automation. In this blog, we’ll explore how to harness the Pi’s capabilities for robust, real-world systems. Hardware Overview Processor : ARM-based SoCs with quad-core CPUs in modern models (Pi 4, Pi 5). Memory : Configurable RAM options (1GB–8GB). Connectivity : GPIO pins, I²C, SPI, UART, and USB 3.0. Networking : Gigabit Ethernet, Wi-Fi, Bluetooth. These features allow the Pi to act as both a controller and a gateway in embedded systems.                                               Raspberry Pi 5 Model, 8GB RAM Types of Raspberry Pi Boards Raspberry Pi makes computers in several different series: Single-board computers (SBCs): The flagship Raspberry Pi serie...

 In this setup, the PC act as the server , and each Raspberry Pi (used with 11) should act as a client : Server (PC) : The PC will be responsible for accepting incoming connections from all Raspberry Pis (11 in total). The PC can manage all connections, continuously receive sensor data from each Raspberry Pi, and send control commands to the Raspberry Pis. The server (PC) can efficiently handle multiple socket connections by using threads or asynchronous methods, allowing it to communicate with all Raspberry Pis simultaneously. Clients (Raspberry Pis) : Each Raspberry Pi will initiate a connection to the PC server. They will continuously send sensor data to the PC (e.g., sensor readings) at regular intervals. The Raspberry Pis will also listen for control commands from the PC and act upon them (e.g., adjusting parameters or performing specific tasks). Key Considerations: Sockets : The PC will bind a server socket to a specific port, and each Raspberry Pi will connect to this server...

To saturate a soil sample in a cyclic triaxial test, you can gradually increase the back pressure until the pore air dissolves into the pore water. This process is similar to the procedure used in static triaxial tests.  Steps  : 1. Insert two saturated porous discs at the top and bottom of the sample 2. Gradually increase the back pressure 3. Perform saturation checks by elevating the confining pressure 4. Calculate the B-value, which is the change in pore water pressure divided by the change in confining pressure 5. If the B-value is greater than 0.95, the soil is considered fully saturated Additional tips  : 1. Use distilled and de-aired water for flushing 2. Apply cell pressure and back pressure in constant increments 3. Allow the sample to saturate for 10–20 minutes after each increment 4. Check the saturation value after each increment 5. The cell pressure should always be higher than the back pressure 6. The cyclic triaxial test subjects a cylindrical soil sample t...