Problem statement.
Arthritis, Parkinson's and other diseases that affect the mobility and dexterity of the hand are all illnesses that take away from the independence of the person affected. Experiencing hand conditions such as these, dramatically hinder an individual’s ability to perform otherwise ordinary and daily tasks. An important task is the application of soaps, creams or liquids to the body, generally for the purposes of hygiene or health. People affected by hand conditions need the assistance of others to comfortably and effectively apply solutions to their bodies. These can be demoralizing and mundane activities, this could be resolved if they were able to be performed alone.
The stigma problem
Many people do not want to advertise their infirmities even to themselves, so its about creating a home device that is subtle and blends in but also to be used by the mass population.
Key Insights.
from user interview & initial research with doctors.
Hard to unscrew the cap.
Easy for the existing product to become messy.
Hard to squeeze the bottle and get the last part out of the bottle.
Concept Ideation
Idea Matrix - Squeeze bottles, Aerosol spray, Pump, Roll on and Massager.
Primary
Research
Through a friend on the course got an insight from Iñaki Artaza, a Spanish geriatrician doctor. After looking at our concepts and gaining a further understanding into our project, he also suggested that we focused on pump mechanisms more than others. He viewed these concepts as a more viable option to people in our target market.
Ergonomics
In order to develop our initial design into a successful product, the product has been engineered to fit ergonomic data for people with limited dexterity. We looked at the dimensions of hands to identify the forces required to squeeze the trigger. We used data from an experiment in which the grip strength of people with rheumatoid arthritis was tested.
Additive
Prototype
The prototype was manufactured using 3D printing. This allowed us to print accurately the complex forms of our design, however encountered many problems during the manufacturing weeks mainly due to inaccuracies with measurements such as threads and pin dimensioning. The main problem encountered, was that the mechanism employed in the prototype design did not work properly due to the lack of space for the cream container to expand inside the applicator. However, it was important not to increase the diameter of the design as this was an important fact for the user. Finally, by decreasing the wall thickness and some redesigning, the last model was printed.
User Testing & Design Thinking
User testing allowed us to identify weak points in the design and also to reassess whether we were solving problems identified by the user.
Design thinking put people first – the closer you stay to the people and the story the better the solution will be.
DFM
The material used in production must also be bio compatible and produce no adverse effects on the skin of user. Polyvinyl Chloride (PVC) is an option that can be used on the outer shell of the product, it is the most commonly used thermoplastic and is used regularly in medical products.
In order to make high quality parts and moulds, considerations need to be taken such as draft angles, large enough radii and consistent wall thickness. The parts made from thermoplastics should also be taken out via core-outs to prevent warping and sink marks which will also result in a reduction in cycle time and material cost.
How is this product
catered for the user?
The applicator head was designing to present a higher surface area improving the application and massage process. The base was designed to be covered by a silicone layer which would make smoother and easier for sensitive skin such as the one of elderly people.
The trigger is placed so that the force is horizontal and designed to be pressed by the user’s palm. This was done on purpose since it is the strongest part of the hand of a person suffering with arthritis
A lid was designed to avoid contaminants coming into contact with the product and making it easier to store away.
Magnets allow the lid to be easy to take off and place on the product without the necessity to exert force or to be accurate.