A Summer of Learning in New Delhi

C.P. Ravikumar, Texas Instruments

It was intensely hot in New Delhi.  After an unusual bout of showers in mid-June, the city was blazing again.  But there was something even hotter that I had gone to witness in the capital city – a summer internship program!

 The phrase “summer internship” conjures up many grand images for a student.  Being able to work on a short-term project under an able mentor, exposure to industrial practices, exposure to new fields, ability to apply your knowledge to solve a problem. Of course, there are fringe benefits to an internship. You may find a mentor who will write a recommendation for you some day. You may make great friends who will help you learn new concepts. Your internship certificate will be a valuable piece of paper that may come in handy some day.

Running a quality summer internship program presents a challenge to any organization. Considerable amount of efforts have to be spent in shortlisting candidates, creating the right content for the internship program, and above all, mentoring the interns.

This summer, the TI India University Program conducted a new experiment by creating a summer internship program in collaboration with an educational institution. Prof. Dhananjay Gadre, who is familiar to my readers (he is the man behind the “lamp” project that I wrote about a couple of months ago), spearheaded the internship program at Netaji Subhas Institute of Technology, Delhi.  Being the director of the Texas Instruments Center for Embedded Product Design at NSIT Delhi, he welcomed this challenge when I spoke to him about it a few months ago. To be frank, this was our second attempt. We tried pulling this off last year, but failed to do so due to some obstacles.

Objectives

The reason why Prof. Gadre readily agreed to the idea was because of his passion for building electronic hardware projects. “I wish to pass on that enthusiasm to the students,” says Prof. Gadre. “There is a fear factor among the students and the goal of this month-long program is to remove that fear as much as possible by encouraging the participants to actually fabricate as many circuits as possible.”

Prof. Gadre took me to his lab, where several projects were in different stages of making. “To a large extent, the success of an electronics hardware project depends on how conversant you are with designing your PCBs,” he said. “Fabricating the PCB and soldering well are great skills to possess. Few people realize that  all this is well within the reach of any engineering college. Our intention has been to avoid the use of any expensive or exclusive equipment. The aim is to democratize the entire hardware building process and to show that everyone and anyone can do it!”

 It is remarkable that in the very first week of the summer internship, all the participants designed their own circuit boards using Eagle and then went about making the PCB, drilling it, soldering it and testing it. In the second week, they made another circuit of their choice.

“Beyond the ability to make a PCB and solder well, we want them to learn how to think from a system point of view,” continued Prof. Gadre. “In order to expose them to system-level thinking, we mandated making a standalone project based on MSP430 or the Stellaris microcontroller.  In such a project, we must pay attention to the requirement of the power supply and select suitable power supply components, clock and reset circuits. For the analog signal chain, there is a need to amplify and filter the signal before feeding it to the ADC.”

Soft Skills

It is hard to emphasize the importance of documentation in any project.  The student interns are learning to document the entire evolution of the project from a stage of conception to a block diagram representation, user interface issues, detailed circuit diagram, flow chart and code, and testing methodology. “We want them to log their progress by taking pictures of various stages of their project,” says Prof. Gadre. “Once all these are documented at every stage, putting together a final documentation becomes very easy and effortless and we are trying to inculcate this habit among the participants.

“Can we expect that the projects will be uploaded to TI’s Microcontroller Projects website?” I asked, and Prof. Gadre nodded affirmatively.

Planning is key!

A lot of planning went into the design of the summer internship program at NSIT, Delhi. Several people helped us out in executing the plan. Vaibhav Ostwal supported us with the necessary tools and free IC samples. Prof. Tarun Rawat of NSIT, Delhi, took care of the entire registration process and many logistics issues.  Rohit Dureja and Shanjit Jajmann who recently graduated from NSIT, together with Nidhi Sharma, a final year student of NSIT, and Rohit Gupta, a final year student of Delhi Technological  University helped in mentoring the students.  Prof. Gadre was there to guide them at each stage.

Fifteen students enrolled into the month-long summer internship program.  I had a chance to meet them in the second week of the internship.  Prof. Gadre briefly explained the process his team had followed. “We gave them a welcome pack, to get them started. Each intern received a backpack with several goodies.  Each participant received an MSP430/Stellaris launchpad. We also included several books, such as the book Art of Electronics and the associated student manual.  We also gifted every student with a box of IC samples that TI had provided. We also included a few other essentials – a general-purpose PCB, wires, passive components, a wire stripper  to unsheathe wires … Next year, I will like to include a good quality soldering iron as part of the kit.”

It is interesting to note that almost all students who are enrolled in the program are desirous of taking part in the Texas Instruments Innovation Challenge. The students were given a choice to work on either the MSP430 platform or the Stellaris platform. Three students elected to work on the Stellaris platform and are being guided by Prof. Gadre, Shanjit, and Rohit Dureja, who, incidentally, are the team who built the Stellaris Guru kit and authored the Stellaris Guru manual The students who have opted for the MSP430 program, are being guided by Prof. Gadre, Nidhi Sharma and Rohit Gupta.

 In the first week, each student was trained in the art of PCB design and manufacturing using the equipment in Prof. Gadre’s lab.  Prof. Dhananjay Gadre is an active member of the FABLAB community and his lab is fully equipped with the equipment to make a two-layer PCB and drill holes. The lab also has a 3-D printer.

Small Projects

We presented a list of 15 projects to the students and helped each of them to pick one.  Each project was chosen to be self-contained and interesting.  The students have already started working on their projects. We encourage them to be independent, but I and my team are available to them for any consultation.”

When I had a chance to speak to the students, I provided them an overview of Texas Instruments and its semiconductor product portfolio. Then I opened the floor to the students. Each student came up to the stage and spoke briefly about the project he/she was carrying out. I was impressed with the nature of the projects and the confidence with which the students presented them.

For instance, there is a student who is working on a Tambola game controller. Tambola is a game of chance and is popularly played in parties. Each participant buys a ticket that has several randomly selected numbers in a matrix form.  A game coordinator picks random numbers from a box and begins to announce them.  For instance, if the first number is 33, each participant who sees the number 33 in his/her ticket will strike it off. The participant who first ticks off all the numbers is the winner.

“I am using MSP430 microcontroller to design the game controller,” said Ritika Malik. “A 10x10 matrix of LED will be used to display the numbers as the game coordinator picks the numbers. The controller has to ensure that a number picked already will not be picked again. It should also be able to recall the last number that was called. I will have to think of a way to achieve these in software. I will also have to address some hardware problems.  The MSP430 microcontroller that I am using has limited I/O pins and I may need some external interface logic to solve this problem.”

There was a good mix of analog, hardware, and software in the projects.  Since each student intern is attempting to build a tiny product, system-level focus is built-in to the program. “We have told the interns that they will have to demonstrate their project in an open house event at the end of their internship,” said Prof. Gadre. “I plan to invite the Director of NSIT to look at the projects.”

We want the participants to continue making circuits even after the workshop. The purpose of providing them a tool kit was to enable and empower them with sufficient material so that they can go on with building circuits at their respective locations. The tool box has all the necessary tools to test circuits on a bread board as well as to make your own circuit board. The component box has over 400 resistors (30 different values), 100 capacitors (ceramic and electrolytic), 50 transistors (small signal and medium and high power), 50 LEDs (all colors), 50 diodes (rectifier and switching) and zeners, 65 ICs (analog and digital), voltage regulators (fixed and variable), sensors (light, temperature, sound), switches, magnets, connectors etc I hope, the participating students, when they finish the program, remain as excited about electronic hardware projects  as they are now and continue to build new and exciting circuits.

References

[1] You can view the pictures taken during my visit to NSIT, Delhi, to meet the student interns here

[2] You can access the blog post “Rub the lamp and make a wish!” about an electronic lamp built by Prof. Dhananjay Gadre and his team, here

 

 

  • I was a participant of this program at NSIT. This is an aggregation of my experiences during the four weeks I spent there.

    The first thing I noticed upon entering the campus is the lush greenery and the brick walled buildings reminiscent of the architecture style of Laurie Baker. The campus is among the most eco-friendly college campuses I have seen. Waste bins were frequently and conveniently located at short distances between each other. Separate bins were provided for bio-degradable and recyclable waste. The granite flooring at the entrance of the administrative building was being cleaned at least 4-5 times a day. Even when it came to the judicious use of technology, NSIT stood apart. On the first day itself, my attention was drawn to the human presence sensors mounted on the ceiling of the mini-audi where the lectures and demonstrations were being held. Even for a small hall that would have a seating capacity of around a 100 or so people, presence sensors which controlled the lighting were installed in each of the three sections of the hall.

    Unlike traditional workshops or programs, the event did not begin with a plethora of boring speeches. In fact, the entire four weeks did not have any speeches, except for the lecture by you, and a short speech by Prof. Dhananjay Gadre on the last day, thanking the mentors, the staff and requesting everyone to provide feedback regarding the program. The straight-out hands-on approach of the program is indeed commendable. On the very first day, Prof. Gadre demonstrated the various projects that were undertaken by his team in the past. Some of them were based on platforms from Texas Instruments such as MSP430 or Stellaris, while the others, which were based on various other competing platforms, gave the students some good ideas on porting these projects and possibly enhancing them using TI’s devices. The session was more of an interaction than a demonstration. Prof. Gadre encouraged the students to figure out how each of the devices work and why a particular mechanism was chosen over other competing mechanisms.

    For instance, one of the projects – an electronic birthday candle – where a programmable number of LEDs light up and the user is required to extinguish them by blowing. Subsequently, birthday music is played. Various methods could be used to detect blowing – microphone, humidity sensor, temperature sensor and so on. A temperature sensor, and an algorithm which detects differences in temperature, was used in the product. Prof. Gadre explained the reason for this choice. A microphone based system will be prone to any background noise and the use of filter to eliminate this noise will be cumbersome and yet not completely foolproof. Humidity sensors may not work well under varying climatic conditions. A temperature sensor will show a change in temperature when a user blows on to it. An argument was made from the audience that an air conditioning duct or a fan could also trigger it. Prof. Gadre answered that if an actual candle is used under those conditions, it would also get blown off and hence this behavior was acceptable.

    When I first read about the workshop, the fee of Rs. 15,000/- (Rs. 13,500/- after the 10% discount for IEEE members) seemed a little bit on the high side. But, upon seeing the workshop kit that was provided, all my apprehensions were laid to rest. In fact, if a photo of the kit was put up along with the announcement, many more students would have found it to be worth it. Apart from a pretty sturdy bag and a TI University program t-shirt, there were a set of four excellent books, a tool kit containing a good quality breadboard, a knife, wire nippers, wire strippers, an eye loupe, single strand wires, and a precision screwdriver set. The components kit, provided subsequently, contained hundreds of resistors, capacitors, transistors and ICs as well as sensors, switches and a pair of super-strong rare earth neodymium magnets.

    The first week focused on circuit design and fabrication. Comprehensive lessons on designing a good schematic and routing it on a PCB were given. A Facebook group of all the participants and mentors were set up within a couple of days and everyone could post their work and get feedback on it. The peer-group model of learning was quite effective in getting everyone to understand the concepts of circuit design. By the end of the first week, every participant had designed and routed at least three circuits and fabricated a simple self-oscillating voltage booster (popularly called Joule thief). The toner transfer method was used to make PCBs. The minimalist joule thief circuit was routed on a PCB which was smaller than a postage stamp. Every step of PCB manufacture, starting from cutting the copper clad glass epoxy board, scrubbing it with sandpaper, transferring the design from glossy paper using a household iron, etching the board using Ferric Chloride, cleaning the etched board to remove toner, drilling the pads, grinding and filing the edges, and applying a protective coating on the finished board, were performed by the participant with proper guidance and safety instructions from Prof. Gadre and his team.

    The second week focused on learning the microcontroller platforms. While the majority of the participants who had enrolled for the MSP430 track of the program were introduced to the MSP430 LaunchPad, the three of us who opted for the ARM based track were provided Stellaris LaunchPads and learned various aspects of programming it with the help of our mentors – Rohit Dureja and Shanjit Singh. Starting from simple LED blinking programs, to using interrupts, timers, analog to digital conversion and serial communication including the USB capabilities of the ARM Cortex M4 based processor. With plans to make a USB based data acquisition system, I performed various experiments on the USB module. The support from the StellarisWare library was extensive. Example codes for various simple USB implementations such as USB Human Interface Device class, USB Generic Bulk Device class and so on were included in the library. By suitably modifying these examples, I was able to set up a PC Volume Control device which used the two push buttons provided on the LaunchPad to control the sound output of my laptop. Subsequently, I developed a PC side application, using Microsoft Visual Studio, to test the speed of data transmission between the LaunchPad and the PC through the USB interface. By suitably adjusting the FIFO buffer sizes, I was able to get a data transfer rate of over 5.0 Mbps.

    From the third week onwards, the focus was on the individual projects by the participants. There was an array of interesting projects especially based on the MSP430 platform. A battery-less RC5 TV remote, powered by the induced voltage from a coil generated by the movement of neodymium magnets, was one of the examples of the low-power capabilities of the MSP430 controller. A traditional remote, retrofitted with the coil, generated power sufficient for 4-5 key presses after a few shakes, while the MSP430 powered remote lasted for nearly 10 key presses. Other interesting projects included a simple temperature readout device which used external and internal temperature sensors, a bicycle speedometer, a multiplication table quiz featuring a random number generation and so on.

    There was quite a lot of enthusiasm from the participants and despite the official timings being from 10am to 5pm, Monday to Friday, the students stayed on till late night working on their projects even on Saturdays and Sundays. Prof. Gadre and his team were extremely supportive of these efforts from the participants and stayed on and guided them. In all, it was quite an interesting experience in the lab. Everyone helped out where they could. Ideas for future projects evolved from discussions during tea and lunch breaks.

    At the end of four weeks, various projects were in different stages of completion. But, like Prof. Gadre said during the first days, what mattered was that each and everyone went through the process of designing a product from scratch. Much emphasis was laid on having the right tools, using the right technique and making the best and most efficient use of the available resources. I am confident that among the people I met during the course of the last one month, almost everyone will continue pursuing project of similar or even more challenging nature and Prof. Gadre and his team will continue their efforts pass on their passion for embedded system design to more and more students, because over the last four weeks I have discovered were my interests lie and I am never going to give up my pursuit for excelling in system design.

    My sincere thanks to TI India University Program, Prof. Gadre and everyone at NSIT!