Engineering Design Example - University of North Carolina...

Dispensers for Safe Water

Engineering Design Example

Origins

Components Fundi made metal stand Rotational molded tank Valve (MIT) Cement - local

125$ cost

Problems Metal durability Cost LDPE Scale

3 liter HDPE blow-molded tank

~30$ --> 2$

~1,000 per day

10,000$ investment in molds

Design: AMM, Kenya

Fit metal and plastic

Installation: BlowPlast, Kenya

October 2010

First step: New tank!

ap

pro

x. 3

0cm

Adapted Designs

Decision to need “nice” Design

Research highlights – Relationship between design and uptake

Investigated 3 firms – Selected PATH/MS firm in Seattle

– Contracted

Provided information on Dispenser and use

Provided design specifications

First Designs - Industrial to Local

Prototype

Molds in China

Final product (almost!)

10.37$ - Kenya

14.00$ - China

Version 1

Next step: Improvements

Field testing – Strengthening due to deformation

Improved lock for perception of security – Attachment kit (lock, bolts etc)

– From China

Commercialization

Next step: NaDCC

Potential Advantages Potential Disadvantages

5 year shelf life (longer time in Dispenser) Less visits and community touches

Smaller volume per dose Not registered in many countries (can’t

piggyback off PSI’s registrations)

Less smell in dosing (“whiff”) Importation of a “chemical”

Cheaper (unknown how much) Dosing more complicated

Less refills needed Unknown CT factors (PATH research less

effective on viruses – unproven d iarrhea)

NaDCC Prototype

daniele.lantagne@tufts.edu

The Design Process is Ongoing