Alcon came to HUI Manufacturing's Medical Cart Development team with a design concept for a cart to house a new ocular surgery system. The customer, being based on the West Coast, initially had some hesitation in working with a Midwest engineering team and manufacturer to supply the carts. However, the HUI Manufacturing Custom Medical Carts team definitively demonstrated their knowledge, responsiveness, and willingness to show up to help the customer whenever needed.
As is the case with many custom medical carts, speed of development was important for the customer. HUI Manufacturing's team was able to meet that aggressive timeline and move from concept to engineering, through development and prototyping rapidly in just over six months in order to begin production as soon as possible.
The Design & Engineering Process
The customer was able to provide a concept for the project that had been developed in concert with their industrial designer. The first task for our engineering team was to take that concept and make a functional model that could be used as a jumping-off point for the development process. Our team built a SolidWorks model of the cart based off the design with manufacturability in mind.
Design for manufacturing and assembly (DFMA)
Our design engineers have extensive experience in the design and manufacture of medical carts and work closely with the teams that actually fabricate and assemble our carts. In fact, our engineers have an average of 24 years of experience working at HUI Manufacturing. This knowledge informs the design: everything from material selection to assembly flow are considered. In the case of this cart, revisions to the bend radii and material thicknesses were needed to be revised in order to make the cart manufacturable.
Peer-to-peer engineering support
We found that one of the most important aspects of the engineering process for this project was the benefit of peer-to-peer access between the customer's engineering team and our design engineers. Because of the complexity of certain components and the compressed timeline for the project, the streamlined communication was a huge benefit in reducing confusion and keeping the project on track.
Challenges & Results
Designing a monitor mounting solution that delivered
The movement and function of the monitors on this cart are vital to the success of the device. While our team did research off-the-shelf options as a budgetary consideration, the design specifications ultimately required a custom solution. The arm that houses the monitors, the monitor brackets, and a connection mount were all custom-designed specifically for this project. Our engineers were able create a custom mount that allowed for finite adjustments of the monitors, while keeping the upper and lower monitors in synch with one another.
Solving for complex cable management
The device monitors are powered via cables that run through the monitor arm down through the cart column. One challenge in this type of setup is to design a cable and monitor arm solution that allows the cables to flex with the movement of the joint, and yet last through the projected lifecycle of the cart.
Cycle testing for verification and validation
Extensive verification and validation testing was conducted to test the ease of movement and durability of the monitor arm. The customer was especially focused on identifying any noise issues that arose with repeated use, identifying fasteners that loosened, and of course verifying that the cable/monitor apparatus was working properly. The arm, mounts, and data cables needed to pass a range of movements over time, including up and down, rotation left and right, tilting up and down.
HUI Manufacturing engineers custom-designed a cycle testing apparatus and program that would test for the customer's specific needs. As a result, this cart endured tens of thousands of testing cycles, with the team making measurements every 1000 cycles and compiling pictures and data for the customer. This provided valuable insights on material selection, arm and mount design, and durability to help guide decisions and provide peace of mind.
Custom component supply chain management
HUI Manufacturing's team provided weekly design review meetings as well as logistical updates for the many custom components used on this project. With unique features requiring tooling builds for the plastic and aluminum parts, it was vital to stay on top of our component suppliers' updates. The unique aesthetics on this project gave HUI the opportunity to find new solutions like the development of a custom metallic powder-coat finish. Additionally, the unique curved surface was less-than-deal for silk screening the decals, so we made the addition of a pad printing service into our portfolio of supplier relationships.
Features & Solutions
- Complex cable management solutions: monitor cables needed to flex with the joints in the monitor arm while ensuring that they last the life of the product.
- Two-coat specialized metallic finish with pad-printed logo graphic: we automated our process to get precise thickness and coverage
- Multiple custom plastic components including gas-assist injection molded tube handles
- Emissions compliance and safety: lower cabinet was built to prevent emissions/interference, which required specialized material finishing
- Specialized ventilation and cooling vents allow CPU to operate properly
- Supply-chain considerations: we work with a third party to warehouse completed carts near the customer to expedite shipments
Looking for more information on monitor arms and cycle testing? We've got a few videos that you will enjoy! Pop on over to our HUI Manufacturing YouTube Channel and check them out!