P19416: Indoor Dry Toilet Base and Manufacturing

Problem Definition

Table of Contents

This webpage summarizes the work done for Phase 1: Problem Definition for MSD I. This page includes summaries, snippets of data gathered, live document links and other information included in the final presentation.

Team Vision for Problem Definition Phase

Project Summary

An indoor dry toilet is a device that doesn’t utilize running water but instead collects waste for manual removal. The seat for this toilet allows for different wastes to be separated and removed more easily. This device should be able to be used by any person no matter their build and should be cost-effective. The current model is usable but some waste can miss the diverters and may not be contained. The plastic seats are also not very cost-effective and takes longer to construct. This device has been in development since 2005 but was put on hold because of the earthquake in 2010.

The end goals of this project is to design and manufacture a full seat that is ergonomically sufficient for all users while also being aesthetically pleasing, and easily movable by a single person. It must also be less expensive than what it is currently while also being 100% usable. The product should be manufactured locally and the management of urinal waste should be easier and possibly customizable in terms of collection methods.

A link to our project summary can be found here.

Use Cases

To understand the requirements of our stakeholders use scenarios were created to determine how our project would be used. Additionally, the scenarios highlight any improvements we could make to improve efficiency.

The use scenarios include:

Below are the use scenarios created.

A general use case can be seen below

Use Scenario

Use Scenario

A user specific use case can be seen below.

User Specific Use Scenario

User Specific Use Scenario

Project Goals and Key Deliverables


Key Deliverables:


A list of stake holders was created to better identify who would be benefiting from this project.



Customer Requirements (Needs)

The Customer Requirements will be used to design the product to best satisfy the customer along with the users.

To decide the customer requirements, an interview was conducted with an employee from SOIL who worked hand-in-hand with the customer during prior iterations of this project.

Weights were assigned to each requirement based on the information obtained from the interview. This priority ranking was done by giving each requirement a number (1, 3, 9); 9 was the highest priority and 1 was the lowest priority. These values will be used in the House of Quality assessment.

A snapshot of the weighted customer requirements can be found below.

Customer Requirements

Customer Requirements

In addition to a snapshot, a link to the live document is included here. This also includes the data for our Engineering Metrics and the House of Quality analysis.

Engineering Requirements (Metrics & Specifications)

This was done to create a list of criteria that is definitive to the product and cannot be swayed by much to help with overall customer satisfaction.

Engineering Requirements

Engineering Requirements

In addition to a snapshot, a link to the live document is included here. This also includes the data for our Customer Requirements and the House of Quality analysis.


Assumptions & Constraints:

1. The final product will be a dry toilet which is ergonomic and moveable

2. Cost of production will be reduced through local manufacturing (<$45)

3. The weight of the product will be easily carried by one person

4. The base of the toilet will be compatible with the 5-gallon buckets being used

5. Diverter will be more ergonomic and work for people of different sizes

House of Quality

This House of Quality was drawn to get a visual representation of what the biggest priorities are going forward. This conclusion was reached by comparing the Customer's Requirements to the Engineering Metrics. We received a prioritized list from the customer and used it to create the house shown below.

House of Quality

House of Quality

In addition to a snapshot, a link to the live document is included here. This also includes the data for our Customer Requirements and Engineering Metrics.

Risk Assessment

We decided that the Risk Assessment should be added to this page, as it is important to know what would be thought of when it comes to issues that could happen in the future.

Risk Assessment

Risk Assessment

Design Review Materials

Our Design Review will be held on September 13th, 2018.

Included here are links to:

Plans for next phase

For the next phase, we plan on moving forward with basic concepts of our design. As of now we plan on:

We will also develop an in-depth project plan after the review has completed.

As individual team members, we have also created personal plans for the next three weeks, which can be found below:

Home | Planning & Execution | Imagine RIT

Problem Definition | Systems Design | Preliminary Detailed Design | Detailed Design

Build & Test Prep | Subsystem Build & Test | Integrated System Build & Test | Customer Handoff & Final Project Documentation