It’s strange how quickly a place can weave itself into your rhythms. 

Hi everyone, and welcome back! I’m writing this blog from home in New Delhi now, but in my mind, I’m still standing on my Nairobi balcony. The same one I once leaned against in uncertainty, maybe even homesickness, my first week there. Back then, the city was a hum of unfamiliar sounds and new faces. Now, that same balcony is a memory that is very difficult to leave behind: the morning light spilling across our apartment, matatus zipping by, and the quiet sounds of the hawks that frequented us. 

I have a feeling, though, that this isn’t the end of a trip; it’s the turning of a page. And the ink from these weeks feels permanent.

The Projects We Leave in Motion

Our work in Kenya wasn’t limited to the walls of the design studio. In the clinics, we gathered valuable clinician feedback on the endometrial biopsy trainer and gastroschisis bag, with doctors asking to stay involved for future testing. Often times the surgeons and OB/GYNs we met with began sketching alongside us, thinking through materials and manufacturing before we’d even packed up our prototypes. I cannot wait to relay all this information to the corresponding teams and get to work back in Houston! 

Back in the design studio, our local projects were also finding their stride. AutoFeto, our digital fetoscope project, now has a working signal-processing pipeline that can detect fetal heartbeats in real time, along with a newly mapped-out path for mobile integration. It’s moving toward app-based deployment, and we are hoping to further work on a bridge between lab testing and real-world clinics back on Rice’s campus.

Our other project, ACE (Active Cast Electrotherapy), designed to prevent muscle atrophy, has grown from a breadboard concept into a fully housed stimulation circuit. Our design review with our mentors has sparked invaluable ideas: integrating dual-circuit control, refining electrode placement, and early considerations for how a future business model might support deployment in resource-limited hospitals.

They’re still works in progress, but they’re already moving toward the future we imagined for them, step by step. Now, our colleagues back in Nairobi, along with our team, will refine, test, and push them further until the day they reach the patients and places that need them most. And when that day comes, we’ll know that a piece of our summer made it all the way there! 

Last Circuits and Goodbyes at Work

Our final days in the design studio were a haze of solder fumes, coffee mugs, and moments you only realize are precious when they’re almost gone. By the end of the week, we’d wrapped most of our testing and documentation, but the room still hummed with the low buzz of 3d printers and quiet chatter.

That afternoon, during our last tea break, we lingered a little longer than usual. The familiar tray of biscuits sat between us, steam curling up from the well-used mugs. One of our mentors, Stacy, had just returned from visiting Rice, and we traded stories – her recounting Houston heat and familiar hallways, me sharing what Nairobi had come to mean. Someone cracked a joke about how, after all these weeks, we still hadn’t boarded a matatu together. We laughed, agreeing it was something to save for “next time,” already picturing it in some future visit.

But beneath the laughter was a quiet ache. I kept catching myself glancing around the room. The workbenches scarred with solder burns, the breadboards tangled in color-coded wires, the sketches taped to the walls. I was trying to memorize it all. This was the space where we’d troubleshot circuits for hours, celebrated a working prototype with impromptu dance breaks, and turned half-formed ideas into something real.

Packing up the studio took longer than it needed to. Each item felt like a keepsake, and when I finally zipped my backpack, it felt heavier than it should have. I realized I was carrying out more than just belongings that day.

Karaoke, Comfort, and Connection

We spent our final night with friends in a manner very characteristic of our time in this city. There was a rooftop dinner and too many “sad” songs at karaoke. It wasn’t a farewell heavy with silence. It was more so joy threaded with the bittersweet awareness that the next time we’d meet might be oceans away. We’ve already started on serious plans for a reunion.

There’s a certain comfort in recognizing that home exists in more than one place. I know now that it exists in the warmth of familiar spices in a meal, in the kinds of conversations that need no translation, and in the kindness that travels between people regardless of where you meet them.

Airports and After

After our keys were turned in, our apartment – once cluttered with half-finished prototypes, laundry hung to dry in the sun, and late-night snack wrappers – stood bare and echoing. We each made our way to the airport at different times, scattering our goodbyes across the day. Mine came with a reluctance you only feel when something has truly ended.

And then, in the most Nairobi way possible, I found myself queuing at security only to look up and see Ellena, my former teammate and now close friend, grinning back at me. We laughed in disbelief, catching up in the cramped shuffle of the line, a small, serendipitous reminder that even in departures, connection has its way of finding you.

When I finally settled into a seat at my gate, boarding pass in hand, the quiet hit me. The rooms I had first entered as a stranger were now the very ones I would give anything to linger in a little longer. It felt like trying to zip a suitcase that’s too full. Each memory pressed in tightly, edges bulging, but you can’t bear to take anything out. 

We left with hopeful promises that we’ll be back. I believe we will.

Thank You!

To Stacy, Eubrea, Dr. June, Dr. Ken, Waka, and Alex – mentors and friends who shaped this summer – thank you for your guidance, patience, and belief. You challenged us to think bigger, supported us when ideas stumbled, and reminded us that every project should serve a purpose beyond ourselves.

To the team that made each day in Nairobi unforgettable – Ellena and Jacey (the best trio I could have asked for!). Every long day in the studio, every shared joke, and every late-night brainstorm made this work as joyful as it was meaningful. And to Michelle, Dr. Lee, and the entire Rice360 team back home – thank you for your guidance, encouragement, and steadfast support! 

You all taught me that innovation isn’t just circuitry or CAD models. It’s in the tea breaks, the shared matatu rides, the problem-solving sessions that spill past midnight, and the way a community holds you up while you try to make something better. For every lesson in design, there was one in empathy – and for that, I’ll always be grateful.

Closing the Chapter

On my last night in Nairobi, I stepped out onto the balcony one more time. The city lights spilled across the hills, just as they had on my first evening here, but everything felt different. Back then, the view seemed like something I was peering into from the outside; now, it felt like a place I had lived inside, breathed in, and carried with me. Somewhere between those quiet mornings in the studio and the long nights debating design criteria, I had stopped counting the days and started belonging. 

Before leaving, I stopped by my favorite café and bought a bag of their dark roast espresso beans – a small way of bottling the city I’d come to love. Now, back in Delhi, I stand on my own balcony, sipping that same familiar taste. The skyline is different, but the warmth the coffee carries is the same. It’s proof that a place can follow you home, tucked into the smallest rituals.

Now, funnily enough, balconies will always remind me that the best chapters don’t announce themselves. They unfold quietly and completely, until you can’t imagine your story without them. I arrived in Nairobi to build new devices and meet new people. I left with a certainty that this is the path I want to walk. These projects will evolve as time passes. But after my time in this city, I’ve learned that the work is only half of it.

The other half is the people. And that part stays with you, wherever you go.

Asante kwa kusoma (thank you for reading) one last time,
Saumya 🛫💌

There’s a word in Swahili – pole pole. It means slowly, gently.

It’s one of the first phrases I heard here in Nairobi, murmured by guides as we went on hikes, mechanics bent over circuits, or whispered by mentors during brainstorming sessions. Pole pole – don’t rush. Let the rhythm guide you. Let things take the shape they’re meant to, in the time they’re meant to.

It’s funny how deeply that word has come to anchor me. A kind of softness, a rhythm of living that hums beneath the rush of traffic and the buzz of circuits, whispering that not all progress is loud. I didn’t know I was searching for that place until I found it. Or maybe until it found me in the quiet chirping outside our design studio each morning. Until I learnt that some of the most lasting things in life, like growth, begin pole pole.

Listening Closely: The Fetoscope Pivot

We started this summer building AutoFeto – a low-cost digital fetoscope to monitor fetal heart rates, originally using a microphone embedded in a 3D-printed horn. But as testing progressed, reality (and physics) pushed back. The mics we sourced struggled to pick up the low-frequency signals we needed. They were also expensive and hard to find locally.

So we pivoted. Pole pole.

We stepped back, reimagined the problem, and began designing a new solution that used what was already accessible – a smartphone. Most clinicians here have a phone with a functioning mic. What if we could harness that?

Soon, we were prototyping a cardboard-based adapter cap. It was lined with foam for sound insulation and could secure a phone on top of a Pinard horn that we printed for testing. We went through a few design iterations. The first was too narrow. The second added flaps and a rubber band system for a better fit. After some tests (and a lot of tape), we started getting audio clear enough to process!

Meanwhile, on the software side, things were moving fast. I converted our MATLAB filtering pipeline into Python for back-end mobile compatibility, added wavelet denoising, and tweaked dynamic peak detection that finally gave us a stable, interpretable heartbeat trace. I also worked on a JavaScript version to create a basic website for proof of concept, but we decided to go the app route for better functionality.

Ellena continued building the front end in Flutter, and now we are exploring methods to integrate the Python code with the code on Flutter. Alex, a friend from the summer program who also happens to be great at computer science, helped us set up a temporary API server so we can run the two pieces of code together. For now, our app and analysis pipeline run on separate servers, but it’s a huge step forward! Our vision is to eventually combine everything into a single device, maybe through Chaquopy (a development kit) and a Java bridge.

We also met with Dr. Lonji, a physician-engineer affiliated with East Africa Biodesign, who gave us invaluable feedback on adoption strategies, including a potential collaboration with a local digital partograph initiative. It’s the kind of next-step thinking that makes this feel real. We’re laying the groundwork for something that lasts. We hope to keep developing the fetoscope after we return, working with colleagues here, and growing the idea beyond our time in Nairobi! 

‘Shocking’ Progress: Active Cast Developments 

While AutoFeto delved into software-land, our other project – Active Cast Electrotherapy (ACE)  for atrophy prevention – was deep in hardware.

We finally got our hands on proper electrodes and watched the stimulation module fire in rhythm. We also did some initial testing on ourselves (don’t recreate at home haha) and felt the stimulation on our forearms! There’s something magical about seeing a signal you built trigger an actual twitch, something physical. We’d stared at breadboards and buzzing wires for so long – to see muscle movement felt unreal. We then soldered both the stimulation and sensing circuits to prepare for our upcoming design review with our mentors.

As the circuits began to take shape, so did the system around them. Jacey designed a compact box that houses the stimulation circuit and power source, making it portable. We’re in early talks about using the same Arduino to power both the EMG and stimulation circuits, an emergency shutoff feature, and user feedback mechanisms for physiotherapists. And as always, we’re thinking ahead about future work with our colleague Waka, physiotherapists, and potential users!

At our design review last Monday, we shared all these updates with our mentors, and their response was very encouraging.

They liked our progress and the functionality of the devices, and prompted us to begin thinking about implementation and sustainability. How would this be maintained in a clinic? Who would fund it? Could a business model evolve from this? All things we have now been integrating with the engineering part of the design process.

Even as our summer winds down, these devices are just beginning. What remains isn’t just circuitry, it’s momentum in motion! 

The Heart of the Work

Our past few weeks were also filled with clinician visits, each one grounding us a little deeper in the realities of the work we’re doing.

It began at Pumwani Maternity Hospital, the largest of its kind in Kenya, where we met with Dr. Mugambi (OB/GYN) to present our Endometrial Biopsy training model. We walked him through the device, had him collect a biopsy sample with it, and talked through the scenarios it was designed to simulate. He was incredibly receptive and gave us thoughtful feedback on the texture and firmness of the uterus and common use cases in Nairobi.

This hospital also has a training center that does city-wide trainings with donated models – something that I am excited to be looking into in terms of future collaborations! I shared these updates with my team and mentors back in Houston, and we are excited to get back to campus and implement everything we have learnt about our project this summer!

Later that afternoon, we tucked ourselves into a microbakery surrounded by swaying trees, sipping coffee and breaking apart hunks of sourdough. We wrote up our findings with (the best) chocolate miso cake on our tongues and sunshine on our shoulders.

Then, the week continued. We compiled our reports and prepared for our next clinical discussion, coincidentally with another Dr. Mugambi (Paediatric Surgeon) to present the gastroschisis bag prototype. My favorite part was seeing how excited he was to talk to us about the device, recognizing the importance of this need in the local context. He immediately began asking thoughtful questions about the material, the sealing method, and the size adaptability.

He also gave us valuable feedback, like considering a single ring versus the current double-ring design, and testing rings of varying diameters to accommodate different neonatal sizes. We’re excited to convey this feedback back to the team in Houston!

But perhaps the most valuable feedback of all was personal. In these meeting rooms, surrounded by innovation and passion, I felt a quiet certainty settle in. Each clinical visit reaffirmed the stakes of our work and the community it serves. I left each hospital overcome by a tidal wave of joy, fulfillment, and a quiet conviction. This is what I came here to do. This is what I want to do. Engineering in conversation with need. Design in conversation with care. I’d never felt so sure, so alive, so fully in motion. And that’s a feeling I hope to carry with me forever.

In the Light of Late Afternoons 

When our laptops closed and the solder cooled, we stepped into a different kind of magic.

Some evenings blurred into thrift store wanderings with friends, fingers brushing faded denim, laughter rising as we picked jackets for each other we’d never wear. Other nights ended with salsa dancing at Nairobi street kitchen, watching the Stewards Cup race at Ngong racecourse, or at a small cinema watching a documentary on Sister Nancy (first female dancehall DJ). We shared a lot of plates and even more memories with new friends who now feel like family. We’re already trying to plan our next reunion! 

And on our last weekend, we took one final trip. Lake Naivasha shimmered like something out of a dream. We set out on our drive early in the morning, seeing the glorious rift valley on our way to Naivasha.

We rode a boat on the lake past families of hippos and a diversity of African bird life: African jacanas, spoonbills, egrets, and ibis. You name it, and it was probably sitting on an acacia tree nearby! We then ate lunch beside grazing zebras and wildebeest at a private sanctuary, and grazed through the surrounding savannah on horseback (equestrian bucket list item!!).

I had the best conversation with our guide, Hamidi, who was a fellow rider and told me about his upcoming showjumping competition at Mt. Kenya. I told him he must visit Jaipur (India) to keep chasing his newest adventure: Polo.

We then drove to Hell’s Gate National Park to see the famous Gorge. I thought it was going to be an easy, scenic trail. Suddenly, we were being asked to slide down sulfur rocks to enter the canyon! It was slippery and a little chaotic, but still, it was an absolute microcosm of the most beautiful natural features. We listened to our guide as he showed us the canyon’s medicines – natural hot springs that the Maasai used after childbirth and the leaves that they crush for healing. We might have lost a bottle of bug spray or two trying to jump across the rocks, but the view at the end was more than worth it!

As we reached the final lookout, the gorge spilled open into a vast green valley, sunlight draping over cliffs and trees in golden sheets. The sight (which inspired the Lion King’s stampede scene!) took my breath away.

As we drove back home, I reflected on this moment. The wild beauty, the silence between the wind and the rock, the knowledge that nature has shaped these canyons for centuries. I felt, suddenly, the smallness of our existence and the vastness of what still lies ahead.

Leaving Slowly

Coming back to pole pole. Back when we first arrived, it felt like a nice phrase. A cultural rhythm I admired but hadn’t yet embodied. 

But now, as this chapter closes, I understand.

This summer unfolded just like that: slowly, deliberately. Through every debugging session, each hospital visit, every late-night brainstorm, and quiet sunrise. The most meaningful things took time – and I’m leaving with a deep reverence for that pace.

From our first hesitant prototypes to final design reviews, from hospital courtyards to zebras grazing beside our lunch table, every part of this summer has felt impossibly alive. I’ve shared dreams with clinicians, laughed with friends in crowded cars, broken bread under starry skies, and scribbled breakthroughs onto the backs of receipts.

I know now that it takes time to learn a place. Time to build something with care, to understand a rhythm not your own. This summer was never about rushing. It was about listening, shaping, and becoming.

And now, as we close our laptops and lift our suitcases, I carry this pace with me. Not just in memory, but in motion.

Until the finale!
Saumya 🍃🌅

Most evenings, as we head home, the matatu drivers by the local footbridge wave at us. Just a quick nod or a smile, the kind of small gesture that slips quietly into your routine until one day, you realize it means something. That maybe you’re no longer just passing through.

This week, that feeling crept into more than just the journey home. Between testing low-cost electrodes, 3D printing wearable casts, and chasing down clean EMG signals, that sense of rhythm kept showing up – in soldered circuits, in shared coffees, and in all the in-between moments that are starting to feel a little more familiar.

Building the Active Cast One Snap at a Time

Our host-site project has taken shape – quite literally – over the last two weeks as we have worked with our colleague Waka at the design studio. The project focuses on designing a low-cost, wearable cast that can actively prevent muscle atrophy by stimulating muscles. The idea grew from conversations about the limitations of traditional immobilizing casts, especially after sports injuries, where muscle loss during healing can lengthen recovery time or limit function.

We began by debating the method of stimulation: PEMF (pulsed electromagnetic field) vs. electrical stimulation via electrodes. PEMF sounded great in theory, but sourcing components locally, cost-effectiveness, and simpler hardware pointed us toward electrical stimulation as the better fit for our context. So, we’ve been designing this circuit for the past two weeks. After finalizing the waveform we wanted (a biphasic square wave to avoid tissue damage), we coded the signal and started wiring the motor drivers and timing components. 

At one point, we accidentally burned through an Arduino board (RIP) – turns out, feeding it more than 22 volts is not a good idea! It also seemed like our multimeter wasn’t picking up the needed output voltage. Some troubleshooting later, we decided to go simple and test the output with LED lights instead… and it worked the whole time, the biphasic output was just too fast to be picked up by our multimeter. Classic. We’ve since cleaned up the design, confirmed the signal on an oscilloscope, and are looking into integrating this model into our cast design! 

Alongside electrical stimulation, we have also been building an EMG sensor (trying to capture real-time voltage signals from muscle contractions) so users can track muscle loss or gain over time. Early testing involved low-cost DIY electrodes made from washers, salt packets from the cafeteria, and hand soap instead of conductive gel (you can’t say we haven’t been getting creative!). At first, we struggled with inconsistent readings, and the op-amps available here weren’t ones we’d worked with before. 

Eventually, we rebuilt our differential amplifier, fine-tuned our reference voltage, and celebrated when we finally got readable signals on the oscilloscope!!

We then moved to designing the physical cast. Our first prototype was a flexible, single-piece sleeve with built-in slots for electrode placement meant to accommodate a variety of hand sizes. But once printed, the structure was too thin to offer any real support, and the electrode holes warped easily. So we pivoted.

We redesigned the cast into a two-part model that snaps together, giving it more rigidity and making it easier to print with more precise dimensions. This version has honeycomb-shaped inserts for electrodes and added thickness along the wrist to stabilize weak areas. It’s still moldable, but should hold up as we do further testing. We’re now going to start thinking about integrating the EMG sensor, the electrical stimulation circuit, and the cast together as one model. 

From Sound to Signal: Troubleshooting the Digital Fetoscope

In parallel with our active cast work, we’ve also been steadily building and refining the digital fetoscope. It’s been a process – writing code, testing filters, debugging hardware – but we’re starting to see clear, consistent signals.

We started troubleshooting last week with the basics: looking into the microphone, op-amp amplification, and a bandpass filter tuned to around 20–200 Hz. The first few days of coding were a lot of long hours. Our base Arduino code was noisy, and attempts to filter it either flattened the peaks or lagged too far behind to be useful. The turning point came when we started experimenting with Hilbert transforms in MATLAB, which helped us visualize the signal’s energy across both time and frequency. The heartbeats were starting to stand out more clearly.

Once we had that working offline, we started translating parts of the logic back into Arduino-compatible code. On Friday, we finally hit a breakthrough: the fetoscope began detecting beats per minute in real-time. The bandpass filter was comparatively stable, the peak detection consistent, and we could finally see those satisfying spikes when we played heartbeat audio near the mic. Progress!

Next up, we’re trying to re-incorporate a wavelet transform to denoise the signal more precisely, now that the base is stable. The hope is to preserve the heartbeat peaks while scrubbing out ambient and mechanical noise, especially from the mic, which keeps mysteriously losing sensitivity. We’re now on the hunt for a mic that can handle a wider frequency range – easier said than sourced, especially low cost. But hey, I love a challenge. Add it to the list of things I’ll be thinking about at 2 a.m. 

Back in the Field: Device Testing + Meetings

Last Wednesday, we delved deeper into our work with the Rice360 devices we brought with us, including the Endometrial Biopsy (EMB) trainer I helped develop back in Houston! It was surreal unboxing it here in Nairobi, where we’ll be testing it with clinicians for real-time feedback. We assembled the magnetic components, checked each tissue insert, and finalized the evaluation surveys for both this device and the neonatal gastroschisis bag.

Later that week, we met with Dr. George Okello, Rice360’s country lead, and his wonderful team. We coordinated clinician visits and feedback sessions with OBGYNs and pediatric surgeons. Sitting in that meeting, I had a moment. This is what I’ve always dreamed of: traveling, learning, and building solutions with real-world impact. And now, I’m in a room where it’s actually happening.

After the meeting, we took a short walk to the Java House down our street – a spot that’s quickly become part of our routine. Over spiced Malindi macchiatos (giving my homemade chai a run for its money!) and a Nairobi breeze strong enough to scatter our napkins, we caught our breath. Everyone was chatting, laughing, and checking in. Our days no longer feel new or uncertain. The same familiarity as the drivers on the footbridge seems to creep in here as well. 

Of Lions and the Coast

Over the weekend, we visited Nairobi National Park, where I saw lions nap beneath speeding trains and ostriches share space with the city skyline. It was a wild juxtaposition, and somehow, it made perfect sense. The edge between city and savanna felt thin, like a reminder that nature and structure can (and do) exist side by side. I’ve found that this feeling echoes throughout Nairobi itself. The city’s architecture feels like freedom: colorful, varied, and full of personality. It’s a city that doesn’t try to look the same, and it’s all the more alive because of it. This energy pulses through places like the Maasai Market – a rotating open-air bazaar filled with vibrant textiles, hand-carved jewelry, and bold paintings. Just walking through it feels like stepping into a palette of Nairobi’s creative spirit.

And just when I thought I’d seen the full range of contrast and color, we arrived in Mombasa.

The plan was simple: take a train to the coast for a weekend of rest and exploration. The reality? All the train tickets were sold out. That wasn’t going to stop us, though. After a sleepy 5:30 a.m. start, we pivoted fast, rerouting through flight bookings at the station and somehow still finding time to stop by the Giraffe Centre, where we fed a three-month-old baby (yes, it was adorable).

With a couple of hours still remaining before our flight, we found ourselves sitting under sun-dappled trees at Cultiva, a farm-to-table spot with amazing brunch and a few wandering cats for company. My aunt, who worked in Nairobi for a year, has been giving us the best food recs!! And then – one flight delay and a 90-minute drive from the Mombasa airport later – we finally made it to Diani Beach just in time for the Summer Tides Music Festival.

That evening, we met up with our fellow Rice CCL interns and local friends, caught some incredible music right on the sand, and found new artists to obsess over (Mutoriah and Nikita Kering – highly recommend).

The next morning, we took the ferry into Old Town Mombasa, which was a maze of coral stone buildings, carved wooden doors, and ocean air thick with salt and spice. As we wandered through the narrow streets, I struck up a conversation with a computer science student working at Nyali Beach for the summer. A few steps later, just outside Fort Jesus (a 16th century Portuguese Fort), a welding technician was crouched beside the road, carefully shaping metal into ornate hinges for a carved wooden gate.

There were sparks flying in the open air, the hum of tools blending with the call to prayer in the distance. It made me smile – we’d had a go at welding joints during the summer program, but seeing that level of precision in action was something else entirely.

Closing the Loop

These past two weeks, our fetoscope picked up real beats, our circuits pulsed in square waves, and we squeezed in some adventures along the way. We made progress in code, in conversation, and in the quiet moments in between.

Each evening, we cross that same footbridge – the one where the matatu drivers now nod as we pass –  and return to a place where our neighbors smile and wave. A place that feels a little more like home. What began as unfamiliar is starting to take shape in the form of the patterns we’re slowly becoming part of. One familiar moment at a time. 

Signing off from our little corner of Nairobi,
Saumya 🏙️⚙️

It’s hard to believe that I’ve already hit the halfway point of my time in Nairobi.

The rustle of fig leaves in Karura Forest.
The sound of a heartbeat through a Pinard horn.
The low growl of a lion carried across the Maasai wind.

These days, my work – and my life here – seems to revolve around listening. Not just to what’s loud or obvious, but to the subtler signals: the shape of a waveform, the comment a clinician makes in passing, the buzz of ideas across a shared workspace.

The past two weeks have been about steady progress in adjusting circuits, refining ideas, and finding a working rhythm, and somewhere along the way, Nairobi has started to feel familiar. 

Pinard Horn, Rewired

Most of our work recently has centered on our digital Pinard horn, a project that’s grown from concept to code in the past two weeks.

The technical goals sound simple: take the analog sounds from a traditional Pinard horn and convert them into clean, usable heart rate data. But every step along the way has been a learning curve, especially for a team of undergrads not particularly versed in wavelet transform.

We began by studying the frequency ranges of fetal heart sounds. Using a method called power spectral analysis, we learned that the key heartbeats – known as S1 and S2 – typically fall between 46 to 57 Hz, while distracting noise like murmurs or ambient sounds often shows up at higher frequencies. This helped us focus our design on isolating those heartbeat frequencies by creating a band-pass filter that keeps signals roughly between 20 and 200 Hz.

Designing the filter meant making some more choices: do we use FIR filters, which give cleaner alignment of signals but are heavier on memory, or IIR filters, which are more efficient but can shift the signal slightly? After running some simulations in MATLAB and thinking about the kinds of devices this might run on in the future, we are leaning toward IIR. It should give us faster results on constrained microcontrollers – ideal for the environments we’re designing for.

After that, it was time to build. We tuned our amplifier setup and debated what our microcontroller of choice should be – Arduino, ESP32, or Raspberry Pi. We rewired the layout more times than I’d like to admit, but the “aha” moment came when we finally got a clear signal, accompanied by much celebration!

Next step? We want to integrate the signal into our heart rate detection code and clean it up with some digital filtering before we start testing. 

New Project, New Pulse

Alongside our digital Pinard horn, our host-site project at Kenyatta University has officially taken shape – a muscle-preserving active cast designed to reduce atrophy during recovery from limb fractures.

We’ve spent the last few days defining our scope, researching existing tech, and mapping out a development plan. After conversations within the team and with our mentors, we are honing in on electrical stimulation as a viable approach. 

The literature review felt a bit like a treasure hunt, and sometimes a rabbit hole. We filtered through studies on everything from mechanostimulation patches to gel-encased wires that vibrate to keep muscles active

Then we began planning our design: What type of current and pulse duration will be safe? Can we embed electrodes in a cast without conductive gels? What kind of materials will allow flexibility and thermal regulation? We developed a scoring matrix with our design criteria, compared stimulation modalities, and are starting to source some components.

It’s early days, but this project is already pushing me to think across disciplines and approach design challenges with clarity and creativity. 

Between Trees and Time

Over the weekends, we stepped away from the studio and into the trees.

We trekked through Karura Forest, surrounded by fig trees and rustling bamboo. Following a winding trail toward a waterfall, we found caves once used by resistance fighters as refuge.

Then came the Masai Mara. My family had flown into town to celebrate my sister’s 18th birthday. We woke before sunrise and climbed into our safari van with flasks of tea and blankets draped over our shoulders. Each morning started with a spirited Twende from our guide Kasaine, and as the sky turned from lavender to gold, the Mara came alive around us. Elephants moved through the morning mist, their silhouettes large and silent. Zebras grazed in loose formation, and Cheetahs rested under acacia trees, eyes half-closed in the sun. We watched a pride of lions stretch and yawn, the cubs tumbling over one another while the older ones looked on. And in the distance, giraffes glided across the savannah, impossibly tall and graceful.

Later that day, we visited a Maasai village, where we were welcomed with warmth, dancing, and stories. We learned about traditional practices, community structures, and the role of oral knowledge passed from one generation to the next. I was struck by how much care was embedded in everything: from beadwork patterns to the way huts were built using local materials. It was a reminder that good design doesn’t always start in a lab or studio – often, it begins with listening, observing, and understanding daily life up close.

There was something grounding in all of it. In the vastness of the savannah, the calm rhythm of life, and the openness of people willing to share their world with us.

I’ll add photos, but I have to warn you that they barely scratch the surface. 

From Here Onward

Back in Nairobi, we marked the end of the Kenyatta medical device innovation bootcamp with one last dinner – a long table at a Brazilian steakhouse, laughter mixing with the clink of glasses and plates piled high. Everyone was dressed up. Conversation flowed, and somewhere in between passing dessert and hugging goodbye, I realized how much I’ll miss this group.

The Rice360 team will continue at the design studio, working on our long-term projects. Our friends from the bootcamp are going to head back to classes, new jobs, and new cities. I can’t help but think about the friendships we have built here that I hope will last long after this summer! 

Another highlight from last week was getting to meet with our mentors, Michelle and Dr. Lee, who were visiting from Rice. I loved seeing familiar faces, and we were excited to share our project updates with them! We really appreciated them making the time to visit. That evening, we all joined students from different Rice programs across Nairobi for dinner, where we had some delicious Ethiopian food (I’m still thinking about the injera and lentils)! We even met with Rice alumni based in Kenya, and I was reminded of how expansive yet close-knit our community is!

What’s Next

We’re deep into the next stage now. We’re building out the active cast prototype, continuing Pinard horn circuit testing, and preparing documentation and material lists. I’m excited for what’s ahead and to see how our ideas start to take shape!

Signing off before the next leopard sighting (or circuit bug),
Saumya ☀️🐆