Pacemakers are life-saving devices for patients with cardiac arrhythmias, but the batteries that keep them running do not last forever. For many patients, that means replacement surgeries every five to seven years, each carrying risks such as infection, lead damage and added health care costs.
For Team Cardion, the challenge was both technical and personal.
The senior design team, made up of Anjali Shukla (BE’26), Nicholas “Nico” Manuto (BE’26), Andrea Perez Pizarro (BE’26), Cesar Ruiz de Castilla (BE’26) and Ella Nevo (BE’26), set out to design an implantable energy-harvesting pacemaker system. Their prototype converts the heart’s natural mechanical motion into electrical energy that can help replenish a pacemaker battery and extend the device’s lifespan.
Their work earned the Technology and Innovation Prize at this year’s Penn Engineering Senior Design Competition.
A Personal Need, A Biomedical Challenge
The idea began with a problem some members of the team had seen up close. Nevo’s mother has a pacemaker and recently underwent a pacemaker replacement surgery. Other team members also had relatives with pacemakers, giving the group an early understanding of the physical and emotional toll of repeat procedures.
“My mom has a pacemaker and recently had a pacemaker replacement surgery, so I was made aware of the process and that there was a need to make the batteries last longer,” says Nevo. “We were all fascinated by the idea of using the body’s motion for battery recharging capabilities, and that interest grew as we researched it more.”
Cardion uses a piezoelectric material, a material that can generate electrical charge when mechanically stressed, attached to the exterior of the heart. As the heart beats, the device captures motion, converts it into electricity and stores that energy for use by the pacemaker.
The system includes a piezoelectric harvester, power management circuitry, a custom printed circuit board, energy storage, a software monitoring dashboard and a mechanical heart model for testing.
Building a Way to Test the Heart
For Michael Siedlik, Lecturer in Bioengineering, the project stood out not only because of its ambition, but because of how quickly the team turned an uncertain idea into a viable engineering plan.
“When Team Cardion first told me that they wanted to design an improved power system for pacemakers, I was skeptical that they would be able to achieve their goals within the one-year senior design class,” says Siedlik. “I am happy to say that they quickly changed my mind.”
The team’s challenge was not simply designing an energy-harvesting system. They also needed a way to test it. Without access to a beating heart, they built a mechanical model that could replicate cardiac motion and allow them to evaluate whether their device could generate and store power.
“The biggest question we had when it came to testing our pacemaker battery was how exactly to test it, considering we couldn’t implant it in the body at its current stage,” says Shukla. “As a result, we decided to build a mechatronic heart model that we could place our third lead on to replicate the movement and force of a heart beat.”
That test system became one of the project’s defining achievements. Siedlik describes it as “essentially a robotic heart,” a tool the team needed to build before they could validate their own device.
Complementary Skills, Shared Ownership
Team Cardion divided its work across hardware, software, testing, integration and commercialization. Ruiz de Castilla led much of the circuitry work, including how to process the power generated by the energy harvester. Shukla, Nevo, and Perez Pizarro focused on testing and the heart model. Manuto led the software components, including the monitoring dashboard.
For Ruiz de Castilla, the challenge was not only generating energy, but preserving as much of it as possible.
“The really difficult engineering problem that comes up when trying to harvest small amounts of energy to extend the battery life of a system as crucial as a pacemaker is that you need to minimize inefficiencies as much as possible,” says Ruiz de Castilla. “Every little thing needs to be considered: the different values for electrical components, the design of the circuit, the structure of the PCB; it’s a problem of trying to squeeze out as much power as possible.”
But the team’s process was not siloed. Weekly meetings, regular troubleshooting and iterative testing helped the group move through setbacks.
“One of the greatest challenges was integrating all of the systems together in a way that produced meaningful, measurable results,” says Manuto. “We overcame this by breaking each part down into even smaller subsystems, and validating them independently.”
Perez Pizarro says the experience showed her what a team with different strengths could accomplish together.
“I learned how much we were able to accomplish by putting 5 people with complementary skill sets and interests together,” she says.
Senior Design With Real-World Stakes
“Team Cardion exemplifies what it means to do senior design in Bioengineering,” says Siedlik. “They immersed themselves in clinical settings to identify real-world needs, lead the design work and carried out rigorous technical validation to build an ambitious biomedical solution.”
While the device would require substantial further testing, design refinement and regulatory review before any possible clinical use, the team sees long-term potential in the idea of powering implantable devices with energy produced by the body itself.
For pacemakers, the impact could be significant. A longer-lasting power system could reduce repeat surgeries, improve patient safety, lower lifetime health care costs and expand access to care for patients in communities where specialized surgical follow-up is harder to reach.
For future senior design teams, Shukla offers a simple piece of advice rooted in Cardion’s own patient-centered beginning.
“Put the patient first,” she says. “At the end of the day, the engineering is important–but the patient experience prevails.”
Ruiz de Castilla’s advice is to treat senior design as a chance to go deeper.
“Use this project to delve into a subject of interest that you may not have gotten a chance to explore as much in your undergraduate education,” he says. “I liked working with circuits, but getting the chance to expand that knowledge into PCB design has been really fascinating.”