Group LPL

 

Our team 

The LPL team is composed of Padraig from the capital of Ireland, Dublin, and the Lauras, two mediterranian souls from Barcelona, Spain. We are an international team with multidisciplinary backgrounds in Biomedical Engineering and Mechanical Engineering studying the Masters in Bioengineering at the Trinity College Dublin. Each of us are specialising in different areas of Bioengineering such as organ culture and computational modelling for tissue engineering, electronics for vital constants monitoring and signal processing analysis for neurodegenerative diseases diagnosis.

Authors

  • Padraig Irwin
  • Laura Pérez Denia
  • Laura Taboada Pascual

OUR projects

We have developed four exciting 3D printing projects, listed below. During the evolution of the projects, we have had the opportunity to learn about many different development stages such as brainstorming, selection and definition of the main ideas, concept development, cad designing, rapid prototyping, 3D printing iterating, and design refinement. 

MODULAR SLING 

sling.jpg

The distal radial fracture is the one of the most common types of fractures, and for reasons that are not fully understood its prevalence is increasing. In the US, at least 1.5% admissions to the emergency department are hand or forearm fractures, and over 40% of them correspond to a radius or ulna fractures. Only in the paediatric population the cost to treat distal radial fractures is of $2 Billion/year in the US. There is very little literature about the prevalence of arm fractures in developing countries, but a study in 18890 adults in Iran revealed that 13.8% of all the fractures corresponded to the distal arm, being it the most prevalent.

Arm fractures require a solid and stable support that allows them to heal with a proper alignment of the bones. A modular plastic sling can provide an alternative to plasters with the benefits of adapting to different arm sizes, reusability of the modular parts and an easy cleaning process. Other applications apart from the arm are a splint for one or multiple fingers, a brace for tennis elbow or a humerus protection. 

splint application

The application of the splint requires that first a cotton dressing is wrapped around the arm in order to protect the skin from the plastic. Then, the pieces are assembled to form the splint and a closing piece is used to close the cylindrical structure. Finally, an external dressing is used to ensure the pieces are kept in place. 

PROFESSIONAL OPINION

"An exciting project aiming to make orthopaedic management materials more accessible and cost effective in low resource settings. This device's strengths include it's customizability, it is lightweight, and durable enough to offer the protection needed. It addresses issues regarding protection against pressure areas through use of cotton underpadding. 

Areas for development would involve fully immobilising the wrist by having the material pass over the joint, and adding a more permanent and robust outer cover to hold the plastic parts in place“

- Conor O’Rourke

Orthopaedics physiotherapist at Saint James’s Hospital

ADJUSTABLE WRENCH

According to the WHO, preventable diseases related to water and sanitation claim the lives of about 3.1 million people a year, most of them children less than five years old. A wrench essential for any health-care facility, regardless of its size, to implement a maintenance programme for medical equipment.

Initial designs of the wrench included sharp corners, which are stress concentrators that could potentially become a failure point. In order to reduce stresses, sharp corners were filleted. A Finite Element Analysis was performed to study the distribution and magnitude of stressess in the wrench when a force is applied in the typical direction expected when using the tool. Check our video to see this effect! 

validation of the device

A simple test was performed to find the failure force. An increasingly heavy weight was hooked to a wrench that was attached to a table edge. The moment of torque, was studied for that purpose: 

        The moment of torque is defined as

              M = F.d

        Where

             M = moment or torque (Nm)

             F = applied force (N)

             d = length of the wrench (m)

 

The device failed when a force of 3N was applied, therefore, the moment of torque required for the wrench to fail is 4.27 Nm: 

       M = (3 x 9.81) x 0.145 m = 4.27 Nm

 

In order to improve the failure point, the length of the device can be improved. It is important to highlight the fact that the failure occur because the pin popped out from its position, and not due to an actual breakdown of the plastic. Therefore, improving the fitting of the pin into its hole would also increase the maximum weight required to break the wrench.

If the length of the device was increased, the maximum torque developed would also increase. It is important to highlight the fact that the failure occurred because the jaws popped out from its position, and not due to an actual fracture of the plastic. Therefore, improving the fitting of the jaws would also increase the maximum weight required to break the wrench.

UMBILICAL CORD CLAMP

The umbilical cord clamp plays an essential role in stopping blood flow and preventing infection after child birth. This project was launched by a previous Med3DP team. Research on this topic has revealed that, when used in the field, some  features of the current design may cut the umbilical cord instead of clamping it. We intend to ameliorate this issue by applying some design modifications and testing the result. 

Features

- Hygienic, safe and reliable to use.

- There is no inner bar, impeding thereby that the umbilical cord is cut.

- Solid grip for easy cord excision.

- Safe and convenient.

- Once the clamp is closed, it cannot be easily opened. Thus, it remains securely in place for the required amount of time.

 

 

Validation of the device

 

KIDNEY TRAY

Kidney trays are used in many medical surgical and non-surgical interventions to dispose any waste products resulting from them. Most kidney trays are made of metals, which are cold to the skin of patients, making the intervention very uncomfortable for them. A 3D printed plastic kidney tray poses a solution for that problem at the same time that it can be provided to low resources areas in which kidney trays might not be a priority item to shift but can be very useful for doctors. By 3D printing a kidney tray that can be further used as a mold for vacuum forming, valuable resources and time will be saved. 

DESign steps

Step 1: A mold was 3D printed.


Step 2: Using a custom made vacuum forming machine at Trinity, a plastic sheet was heated.


Step 3: Once the plastic sheet reached the forming temperature it was forced against the 3D printed mold by a vacuum. 


Step 4: Any excess material on the plastic sheet was removed creating the final shape

FEATURES

- Light in weight.

- Easy production.

- Fast manufacturing process.

COST ANALYSIS 

tau2.PNG