TASK 11: Writing Resource Article using Markdown

LEARNING OBJECTIVE:

The aim of this task was to learn how to use Markdown as a lightweight and efficient markup language to create technical resource articles that can be shared across platforms in a consistent format.

LEARNING:

Markdown is a plain-text formatting syntax that allows writers to create structured documents without relying on complex text editors or HTML. It supports headings, lists, hyperlinks, images, and code blocks while remaining simple and readable in its raw form. The key advantage of Markdown is its device agnostic nature, ensuring that the formatting remains consistent whether viewed on a website, a mobile device, or within version control platforms like GitHub. In this task, I chose a technical topic of interest and created a resource article entirely in Markdown. I learned how Markdown simplifies formatting, enhances readability, and integrates seamlessly with platforms such as GitHub Pages, static site generators, and content management systems.

OUTCOME:

I successfully wrote and formatted a technical resource article in Markdown and published it on the MARVEL website. This task gave me hands-on experience in technical writing using Markdown, helped me understand its versatility in documentation and blogging, and improved my ability to convey technical concepts in a clean, structured manner.
All relevant images are added to visually show what I have done.

TASK 12 : ACTIVE PARTICIPATION

TASK 13: 3D Printing

LEARNING OBJECTIVE:

The aim of this task was to understand the working of a 3D printer, learn about STL files, slicing software, and important parameters like bed temperature and infill density, along with gaining knowledge of the types of 3D printing technologies.

LEARNING:

3D printing, also called additive manufacturing, is the process of creating three-dimensional objects layer by layer from a digital model. Unlike subtractive manufacturing (cutting or milling from a block), 3D printing builds up material only where needed, making it efficient and versatile.

The workflow begins with an STL file (Stereolithography format) that represents the geometry of the model as a mesh of triangles. This file is processed using a slicer (such as Ultimaker Cura or Creality Slicer) that converts the geometry into G-code, which contains the instructions the 3D printer follows to move the nozzle, control extrusion, and set print parameters.

Important slicer settings include:

• Bed temperature: Ensures adhesion of the first layer to the build plate.
• Nozzle temperature: Melts the filament correctly for smooth extrusion.
• Infill density & pattern: Controls the internal structure and strength of the object.
• Layer height: Defines resolution (thinner layers = smoother prints but longer times).

Types of 3D Printing Technologies:

1. FDM (Fused Deposition Modeling):
   The most common type, where thermoplastic filament (like PLA, ABS) is melted and extruded layer by layer.

2. SLA (Stereolithography):
   Uses a UV laser to cure liquid resin layer by layer into hardened plastic, offering very high resolution.

3. SLS (Selective Laser Sintering):
   A laser sinters powdered material (nylon, polymers, or even metals), fusing them together layer by layer.

4. DMLS/SLM (Direct Metal Laser Sintering / Selective Laser Melting):
   Similar to SLS but with metal powders, enabling industrial-strength metal parts.

5. PolyJet/MultiJet Printing:
   Sprays photopolymer droplets and cures them with UV light, allowing full-color and multi-material printing.

Although the 3D printing task could not be completed practically due to the machine being occupied, I gained a strong theoretical understanding of STL files, slicing, critical print parameters, and the different types of 3D printing technologies, which are widely used in prototyping, manufacturing, medical applications, and product design.

OUTCOME:

While practical printing could not be performed, I thoroughly studied the theory behind 3D printing, its workflow from digital model to sliced file, and the various technologies used. This knowledge provides a solid foundation to operate the 3D printer effectively when given access in future tasks.

TASK 14: Study of L293D Motor Driver

LEARNING OBJECTIVE

The aim of this task was to study the datasheet of the L293D motor driver, understand the internal IC structure, and explore related concepts such as PWM and H-bridge motor control.

LEARNING

About L293D Motor Driver

The L293D is a quadruple high-current half-H driver IC that allows DC motors and stepper motors to be driven in both directions. It is commonly used in robotics and embedded systems where bidirectional motor control is required.

The IC has two H-bridge circuits, each capable of driving a motor independently. It can drive two DC motors simultaneously, with control over both direction and speed. The chip also has internal diodes for back EMF protection, making it suitable for inductive loads such as motors.

IC Specifications

• Voltage supply (Vcc1): 5V (logic voltage)
• Motor supply (Vcc2): 4.5V to 36V
• Maximum output current per channel: 600 mA (peak up to 1.2A)
• Number of drivers: 2 (each with 2 inputs and 2 outputs)
• Protection: Internal clamp diodes for motor back EMF

H-Bridge Concept

An H-bridge is an electronic circuit that enables a voltage to be applied across a motor in either direction. It consists of four switches (transistors or MOSFETs) arranged in an "H" configuration:

• Closing one diagonal pair makes the motor rotate clockwise.
• Closing the opposite diagonal pair makes it rotate counter-clockwise.
• This mechanism allows bidirectional control of DC motors.

The L293D integrates two H-bridges, making it compact and efficient for driving two motors.

PWM (Pulse Width Modulation)

The speed of the motor is controlled using PWM signals applied to the Enable pins (EN1, EN2) of the L293D. By varying the duty cycle of the PWM:

• A higher duty cycle → motor runs faster.
• A lower duty cycle → motor runs slower.

Thus, the combination of direction control through H-bridges and speed control through PWM allows full motor control.

Applications

• Robotics (driving wheels or arms)
• Line-following robots
• Stepper motor drivers
• DIY embedded projects using Arduino, ESP32, or Raspberry Pi

RESOURCES

https://www.ti.com/lit/ds/symlink/l293d.pdf?ts=1757938144845&ref_url=https%253A%252F%252Fwww.google.com%252F

OUTCOME

Through this task, I understood the working of the L293D motor driver, including its internal IC configuration, the role of H-bridges in enabling bidirectional motor control, and how PWM signals regulate motor speed. This study provides the foundation for implementing DC motor control in embedded systems and robotics applications.

TASK 15: INTRODUCTION TO VR

Learning objective:

Understand the technical and experiential differences between Virtual Reality (VR) and Augmented Reality (AR), examine current industry trends, outline the common technology stack used to build XR experiences, and highlight notable Indian companies active in this space.

1. What are AR and VR ?

AR: AR overlays video or images onto a display of the physical world, typically through a smartphone. The overlaid image creates an interaction between the user, the digital, and the physical worlds, allowing them to make connections or have new experiences. AR and CGI allow for the visualization of objects in the real world. To create an AR experience, you need a device with a camera and software that uses the 3D elements with the AR application. Some popular examples of AR include entertainment-related options like Snapchat filters and the mobile video game Pokémon Go, but it also has implications for business training.

VR: Unlike AR, virtual reality works by creating a fully immersive experience using a headset and computer-generated images (CGI) to put the user in a virtual world. In VR, the user interacts with a fully virtual world using a headset and a controller. Virtual reality creates a sensory experience by stimulating and tricking the sensory organs into interacting with the virtual world as they would the physical world.

2. Current trends & market outlook

• Augmented Reality (AR) And Virtual Reality (VR) Hardware market size has reached to $62.52 billion in 2024

• Expected to grow to $262.69 billion in 2029 at a compound annual growth rate (CAGR) of 33.4%

• Growth Driver: Cloud Gaming Driving Growth In The Market By Enabling Seamless Access And Expanding Player Base

• Market Trend: Innovative Enterprise-Grade VR Headsets Driving Growth In The Market

• North America was the largest region in 2024 and Asia-Pacific is the fastest growing region.
  Useful stats: The augmented reality (AR) and virtual reality (VR) hardware market size has grown exponentially in recent years. It will grow from $62.52 billion in 2024 to $82.88 billion in 2025 at a compound annual growth rate (CAGR) of 32.6%. The growth in the historic period can be attributed to increasing adoption of the internet of things (IOT), growing use of smartphones, increasing emphasis on product visualization, growing demand for electronic devices, and growing adoption of smart devices.

3. Indian landscape — companies and use cases

AjnaLens: India's top XR company, developing mixed reality headsets and an "AjnaVidya" platform for technology-driven, immersive learning and enterprise solutions.

Tata Elxsi: Combines engineering and design to provide comprehensive AR and VR solutions, with a strong presence in the automotive, aerospace, and healthcare sectors.

Simulanis: A multi-award-winning XR company that builds engaging, interactive, and immersive AR-VR applications primarily for industrial training in manufacturing-based sectors.

PlayShifu: An Augmented Reality-based company that creates interactive toys and games designed to provide educational play experiences for children aged 4–12.

Irusu: Pioneers in VR and AR technologies and manufacturing VR headsets in Hyderabad, also providing VR/AR/XR lab setups for schools and universities.

Quytech: A development company specializing in leveraging AR, VR, and other emerging technologies to create custom applications for a diverse range of industries.

4. Challenges & open problems

Hardware costs: High-end XR devices require expensive components and complex miniaturization, hindering mainstream affordability.

Battery/thermal limits: Powerful processors for demanding graphics clash with long battery life and wearable form factors, leading to devices that are either bulky, run hot, or have limited operating time.

Content creation bottleneck: Producing compelling and high-quality XR experiences is resource-intensive and requires specialized skills, slowing the growth of a robust content library.

Privacy & safety: XR devices collect highly sensitive biometric and spatial data, raising significant privacy risks, while immersive virtual spaces can introduce new forms of harassment and safety concerns.

OpenXR progress: While the OpenXR standard is advancing to improve cross-platform development, ongoing work is needed for full industry adoption and to prevent fragmentation as devices and features evolve.