Industrial design BA (hons) degree project
For my final year honours project in Industrial Design I designed a Home Cycler-Assisted Peritoneal Dialysis Machine for children suffering from kidney failure. Dialysis is the treatment used to filter the blood of toxins and excess water when the kidneys no longer function properly. A CAPD machine controls the treatment, which take place inside the child’s body using their own natural peritoneal membrane to filter the blood through osmosis. This is usually done when the patient sleeps. I designed a new product called the dream doctor which replaces the complicated and time consuming set up system with just one pack. This reduces the risk of peritonitis infection by 70% as the number of connector sites was reduced from six to one. Also set up time is reduced from 20 minutes to 3 minutes.
PUTTING THE USER FIRST
A detailed research report was drawn up at the beginning of the design process, putting the user and industry needs to the fore, I recieved the highest mark for 5 years in the industrial design honours degree program for this report. You can download this report by clicking the button below.
HUMAN CENTRIC DESIGN
USING PROBLEM SOLVING SKILLS TO ITERATE THE BEST SOLUTION
Dialysis is a medical process through which a person’s blood is cleansed of the toxins the kidneys normally would flush out. It is generally used when a person’s kidneys no longer function properly.
The DREAM DOCTOR machine uses just one fluid pack containing a sterilised water bag with the required electrolytes, buffers and osmatic agents, the pack also contains a separate mixing bag. This cuts the instances of peritonitis infection sites from 7 to just 1, as there is just the patient line to be attached to the machine. The machine now takes seconds to set up, and is portable enabling the child to move around freely meaning they are not restricted to their bed. It can also be taken off the stand and placed on a tabletop; this can be a good feature if the child is away from home. No storage area is needed as everything is contained in the one pack.
DESIGN AND PRODUCTION
FEATURES AND FUNCTIONS
A peristaltic pump controls fluid flow from the sterilised water bag to the mixing bag. The machine pumps the required amount of sterilized water into the mixing bag; a separate cartridge containing dextrose in a powder form injects the prescribed amount into the bag. This is then mixed and heated using ultrasonic waves. A valve releases the fluid into the patient line. The patient’s peritoneal membrane fills with the fluid, the valve closes and the fluid is held there for the required time, when the valve opens it creates a negative pressure causing the fluid to drain from the child’s abdomen and into the waste line. This cycle continues through the night up to 5 times, an alarm sounds to alert the patient if there is a problem with the machine such as an obstruction in the line, which can happen if the patient lies on it. A new treatment card is inserted into the machine, this contains the therapy settings prescribed by the physician and the card also records treatment results form the therapy.
HOW IT WORKS
CNC RAPID PROTOTYPING
A scale model was manufactured using the CNC rapid prototyping machine. See images below of the process.
DIAGRAMS, SCHEMATICS, INTERFACE AND DESIGN THINKING
Below is a selection of sketches and design iterations, a process of thinking though the challenges that this complex system required in order to facilitate a new and radical design solution.