Imagine a scenario where seconds can be the difference between life and death. Picture remote villages, disaster-stricken areas, and underserved communities where access to critical medical supplies is a challenge. In such settings, medical delivery drones are not just a technological marvel; they are lifelines. These drones have the power to transcend geographical barriers, overcome logistical hurdles, and bring much-needed medical relief to those in desperate need.

In this article, I want to highlight an inspiring drone design project by Frank Lucci, a high school student out of Texas, who used SimScale’s CFD simulation tool to design a medical delivery drone from scratch. The possibilities that cloud-native simulation like SimScale can provide students and designers with are endless, enabling them to design faster, iterate more, and accelerate their innovation in ways that are otherwise beyond reach.

The Promise of Medical Delivery Drones

The key factor that has accelerated the adoption of drones for medical delivery has been the recent surge in the need for such delivery of medications and vaccines on a global scale, characterized by the impact of the COVID-19 pandemic, especially in areas facing geographical obstacles and a lack of reliable refrigerated transport.

One initiative by The World Economic Forum called Medicine from the Sky has been implemented in India, which is known for its diverse and hard-to-reach landscapes. The need for healthcare access in rural Indian regions has been a clear incentive for public and private organizations to invest in and push drone solutions. The initiative’s initial phase successfully conducted over 300 drone-enabled vaccine deliveries in Telangana, India, making it a pioneering initiative in Asia. The project then shifted its focus to the more complex terrain of Arunachal Pradesh, a Himalayan state characterized by challenging mountainous landscapes. In this phase, the initiative carried out over 650 drone flights and delivered over 8,000 medical products to 200+ patients across challenging terrains.

The challenges of medical delivery are multi-faceted. Time is often of the essence, and access to healthcare can be a matter of life and death. Traditional ground-based transportation systems may be slow and inefficient, especially in remote or disaster-stricken areas. This is where medical delivery drones step in. They offer the promise of faster response times, reduced costs, and improved access to healthcare, particularly in emergencies and underserved regions.

MediWing: A Medical Delivery Drone Design Project

Frank Lucci is a student at the BASIS San Antonio (Shavano) High School in Texas, an ardent learner of fluid dynamics and aerospace, and a member of the SimScale community. In his effort to participate in a science fair competition, Frank took the COVID-19 pandemic as a motive to design, build, and fly a drone that delivers medical payloads. Thus, his project MediWing was born.

After considering the design requirements of a medical delivery drone, including range, speed, payload weight, and modes of flight, he used some rough estimates to come up with an initial base design. The design involved a drone with airfoil-shaped wings. So, he created an initial CAD model and used SimScale to simulate and reiterate the design numerous times until he reached the optimal design. He, then, developed a detailed CAD design for a half-scale model and constructed a physical prototype using CNC and 3D printing technologies. He went on to test and tune the prototype until the drone was able to fly autonomously.

Here’s what Frank had to say about his prototype:

“The package mechanism and everything else seemed to work except for the range, which was half of the predicted and desired range. Eventually, I came to understand that all the building defects, circular flying patterns, and high wind speeds cause a huge efficiency decrease. I vowed to construct the next model way more aerodynamically efficient and overestimate the drag predicted from the simulations. After one year, hundreds of hours of work, thousands of errors and failures, and one Top-300 middle-school science fair project in the nation, Version 1 was done.”

However, Frank was not done there. He went on to design a second version of the MediWing, seeking a VTOL (vertical take-off and landing) aircraft design. Frank is currently working on optimizing his design to accommodate and fix the plane’s VTOL transition and is even considering building a full-scale version.

Frank’s use of SimScale CFD to analyze and visualize the airflow around the drone has helped him fine-tune his design effectively and facilitated his ability to innovate faster. This is exactly what SimScale offers: Unparalleled accessibility and seamless integration. With more and more students finding significant value in SimScale, SimScale continues to support academics, engineers, and designers to build the future and innovate faster and better.

Read more about Frank’s story in his entry in the SimScale Forum.

CFD Simulation for Medical Delivery Drones

Computational Fluid Dynamics (CFD) plays a critical role in shaping the design and functionality of medical delivery drones. By leveraging CFD simulations, engineers can predict and analyze how a drone will perform in various conditions, including different wind speeds, temperatures, and altitudes. This enables them to optimize the drone’s aerodynamics, stability, and payload-carrying capacity before a physical prototype is even built.

CFD simulations provide crucial insights into the airflow around the drone’s body, rotor design, and other components, allowing for fine-tuning of the design to maximize efficiency and safety. The result is a well-engineered drone that can reliably transport life-saving medical supplies to those in need.

Drone design projects like Frank’s MediWing rely on CFD simulations to ensure the drone meets stringent design requirements, complies with safety regulations, and performs optimally in challenging real-world scenarios.

The real-world implications of such innovative projects can be profound. With initiatives like that from the World Economic Forum, we do not need to imagine anymore. We are getting closer to a world where medical supplies, vaccines, and even organs can be swiftly delivered to remote areas, disaster-stricken regions, or areas with limited infrastructure. As such, lives can be saved, critical treatments can be administered on time, and healthcare access can be extended to the farthest corners of the world. The successful deployment of medical delivery drones not only addresses the challenges of today but also paves the way for a more equitable and efficient global healthcare system.

The post Wings of Hope: CFD-Enabled Design for a Medical Delivery Drone appeared first on SimScale.

To assemble, the BPM Connect uses snap-fit joints just like many compact devices from the medical and electronic industry. Snap-fit joints are a commonly used design for connecting plastic parts. They are a good replacement for fasteners such as screws or rivets, as they weigh less and are easier to assemble. Moreover, they are easy to deploy as they can be directly assembled after injection molding without any post-processing. However, designing the right snap-fit joint can be very difficult and expensive. Validating the correct function of snap-fit joints can be prototype-intensive. Additionally, mock-ups don’t represent the actual assembly well because they have different material properties due to the different manufacturing processes (CNC-modeling vs injection molding).

Enter SimScale! Simulation can help reduce the number of prototypes leading to shorter design rounds. Using SimScale, an engineer can calculate insertion/extraction forces and can visualize section stresses to recognize problematic zones inside the snap-fit material. This is important to allow a design-for-assembly approach.   

In this article, we demonstrate the structural analysis of the snap-fit joint shown in the image below, which is similar to the ones used in the BPM connect. We will discuss how a company like Withings is able to reduce their design-to-prototype cycles from weeks to days by leveraging the power of the cloud for simulation.

Case Study: Structural Analysis of a Snap-Fit Joint

This case study deals with a static structural setup. However, it is also a nonlinear analysis due to the large deflection of the beam and the nature of the physical contact between the catch and the mating part. The insertion and extraction of the snap-fit are imposed by defining the displacement or movement of the plastic casing in dependence of time. The goal of this design study is to visualize and calculate the maximum stresses, deformations, and mating forces for different tolerances of the same design. We will be considering three different cases: 

1. A nominal case
2. Minimum tolerance values and the smallest gap between catch and mating part
3. Maximum tolerance values and the largest gap between catch and mating part

Simulation set-up 

The first step is to import the CAD geometry either by uploading a file (drag & drop) or by importing directly from your preferred CAD tool. SimScale supports the import of most common CAD file formats, and also provides CAD Associativity for OnShape, Solidworks, and Fusion 360  meaning that you can switch CAD geometry and the simulation assignments of loads and boundary conditions and materials are automatically applied to the new geometry. This is useful in this project as we do not need to redo any assignments when changing between the tolerance cases. Simscale also allows for the setup of templates that can be used by engineers with less experience in simulation. 

The next steps in the simulation setup are defining the physical contact between the catch and the mating part, setting the materials, and defining the boundary conditions. The beam is defined to move into the mating part and out of it again.

Snap-Fit Tolerance Study

The image above juxtaposes stresses in the three different tolerance cases. These three simulations ran in parallel to each other. In SimScale a new virtual machine is started in the cloud with every simulation run. This means that if one simulation takes one hour, ten simulations will also take one hour. This parallelization allows for iterative simulations in early-stage design. 

We can clearly see how on the right the stresses are highest due to the fact that the gap between both parts is small. In the next plot, we can see the required forces to insert and extract the snap-fit. As expected, the tolerance with the smallest gap requires a significantly higher force than the other two cases. An engineer can judge if the mating force, in this case, is too high for ergonomic assembly and disassembly of the snap-fit. Conversely, in the case with the largest gap, the extraction force might be too small such that there is a risk that the snap-fit can loosen or break apart. SimScale provides a powerful tool to assess these design concerns.

Benefits of Nonlinear Simulation

This case study shows how nonlinear static analysis in early-stage design allows engineers to optimize the design for an efficient assembly and also for correct functionality. With SimScale, Withings is able to validate the correct function of snap-fit joints, like those used in their at-home and wearable medical devices. The accessibility of cloud-native engineering simulation enables designers and engineering teams to leverage parallel computation capabilities and achieve faster design cycles and more robust design insights.

To learn even more about this nonlinear mechanical optimization study, watch our on-demand webinar with Withings. Simulation experts from Withings and SimScale showcase how to accelerate the design-to-prototype cycle of medical devices:

The post Leveraging Simulation to Accelerate the Development Cycle of Withings® Medical Devices appeared first on SimScale.

Student Ambassador Spotlight: Mohammad Fozan

While completing an undergraduate degree at NED University of Engineering and Technology, Mohammad learned about SimScale through connections on LinkedIn and subsequent research regarding cloud-based simulation platforms. From there, his interest in engineering simulations led Mohammad to develop a deep understanding and preference for the SimScale platform.

“I am a Mechanical Engineer by profession, and computational fluid dynamics (CFD) and fluid mechanics are key areas of my interests. I was selected as a SimScale Ambassador in March 2018, and since then I have been actively working in collaboration with SimScale. Recently, I was invited by faculty members and the Chairman of the Biomedical Engineering Department, SSUET, to conduct a technical workshop.” – Mohammad Fozan

The workshop was made possible by Dr. Maryam Raziq, Prof. Dr. M. A Haleem, Chairman Dr. Zia Mohy Uddin, and Muhammad Shahjehan Zafar. Additionally, SimScale’s very own Jousef Murad, SimScale Academic Program Manager, provided great support before, during, and after the event. 

The Workshop: Applications of FEA and CFD in Biomedical Engineering

The workshop took place at the end of February 2019 and was comprised of 3 sessions. The first session addressed hip prosthesis, where students conducted finite element analyses (FEA) to evaluate the displacements, stresses, and strains on the hip prosthesis and femur. To learn more about prosthesis design, check out this Workshop.

Session two of the workshop also involved FEA, and participants ran static analyses of cardiovascular stents to check for deformations.  This exercise focused on the testing of two different types of cardiovascular stent models (shown in the figure below) with the overall aim of determining which stent type and material were best for treatment.

The final session of the workshop switched gears, as students were asked to perform 3 different computation fluid dynamic (CFD) simulations to analyze the flow of blood as a non-newtonian fluid through a Carotid Artery Bifurcation.

The simulations were performed for 3 cases—the first, with a healthy blood vessel with no calcification or blockage; the second, through a moderately calcified blood vessel and the third, through a severely calcified or occluded blood vessel. The results will show the differences in pressure, velocity profile, and the outlet flow through the two branches.

Simulation Setup With SimScale

For the final session, the CAD geometry of the artery was simplified and imported into the SimScale workbench. A split operation was then performed to split the faces for boundary condition specification. The material point was specified inside the vessel geometry, and the bounding box was created to cover the whole vessel geometry. Next, the mesh was created with region, surface and feature refinements as layers were added on the walls of the artery to resolve the boundary layer. Hexahedral cells were used in the mesh, and in the cases characterized by vessels with calcification, the calcified portion of the vessel was also further refined with region refinements. The artery walls were modelled as no-slip walls. Mass-flow rate of 0.0044 kg/sec was specified, and the vessel inlet and outlets were set to zero-gauge pressure. After grid creation, incompressible steady flow analysis type was specified. The flow was considered to be turbulent and k-w SST turbulence model was used for closure because of its robustness. The blood was modeled as Non-Newton fluid with Bird-Carreau viscosity model and fluid “blood” was specified on vessel i.e., flow domain.

“The benefits of CAE and using SimScale were clear as the problem could be promptly investigated, and the blood flow behavior could be studied quickly.”

Simulation Results

Each simulation took approximately 30 minutes on 8 cores. Using SimScale, the students were able to assign area-average and area-integral to inlet and outlet faces of geometry respectively to calculate and compare blood pressure and velocity values in all three cases. Participants achieved a very good y+ value of approximately 1. In the final session, it was found that pressure drop along the length of the blood vessel is largest in 85% calcification case as expected and lowest in the normal case with no calcification.

What are the Next Steps?

As the workshop was a roaring success, there is interest in hosting similar biomedical workshops across universities in Pakistan in collaboration with SimScale in the future.

To learn more about SimScale’s biomedical engineering webinars, fill out this form to watch our workshop video series on YouTube.

Keep up to date with all of our upcoming workshops and webinars here.

The post SimScale’s Student Ambassador Holds Biomedical Engineering Workshop appeared first on SimScale.