Near Zero Waste Children's Furniture

Final year student project

A design project on furniture made of mycelium-based composite

The current ‘Fast furniture’ phenomenon, as a result of rapid changing trend has generated significant amount of waste. Consumer’s preference of disposing of furniture to landfill has been suggested due to their lack of awareness in the disposal infrastructure. Hence, the idea of ‘zero waste’ was to implement a waste elimination scheme for a more sustainable product life- cycle. Short life cycle of children’s furniture due to unable to keep up with the physical development of children, has inspire the development of a near zero waste children’s furniture.

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My Contributions
As a major individual design project, I was delegated as the main contributor for the project, under the guidance of a member of university staff.
The project spanned over a year and was divided into two stages.
The first stage, known as Stage I, involved two research studies that assisted in defining the problem and various design decisions. These studies comprised of research on ergonomics, standards and regulations, and a comprehensive market analysis of the children's furniture industry. Stage II focused on concept generation and selection, prototyping and proof of concept, as well as a final solution review. Additionally, suggestions were made regarding the product life cycle, and an eco-audit was conducted

Material testing and analysis

Prototyping

Autodesk 3Ds Max

Autodesk Inventor

Standards and regulations

Product design and development

Eco-audit

Matlab

Market research and analysis

Manufacturing processess

Furniture made for children is prone to be having shorter product life cycle compared to other types of furniture, due to furniture unable to accommodate their physical growth. Existing solution, for instance, adjustable furniture which can adapt to the physical development in children's body. However, not so much has been put into development in regard to the end-of life considerations of these products.
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Near- zero waste children's furniture is a concept built to explore solution for a sustainable, functional piece of children's furniture that pursue the ideology of ' Zero Waste'.
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What is "zero waste"
Zero waste is a philosophy of waste elimination implementation for a more sustainable product life cycle.
This does not refer to only waste elimination at the production stage but considering how materials flows through the entire product's life- cycle, as opposed to end-of pipe management.
The definition of "Zero waste" was defined by the Zero Waste International Alliance as follows:

" Zero waste : the conservation of all resources by means of responsible production, consumption, reuse, and recovery of products, packaging, and materials without burning and with no discharges to land, water or air that threaten the environment or human health"

Within the 'Zero- Waste ' model, materials are reused, repaired, sold, or redistributed within the system when they reached their end of life, implying a circular system.

Linear and cyclical resource flows

The Design Process

Click to reveal details about the process

01

Initial Research

Identifying the problem or need that the project is trying to solve. Gather information about the problem, including relevant background information and any constraints that must be considered.
Several research studies were produced during this stage, in which these documentation has been supporting the development of some aspect of the design.
1. Ergonomics studies
2. Standards and regulations
3. Market analysis and consumer behaviour

02

Concept development

Generate a range of possible solution to the problem. Evaluate each possible solution based on its feasibility and other relevant criteria and design specification.
There were 2 concept generation in this stage, where the 2nd concept generation was an initiative to explore more possibilities and directions. Research studies were also produced to evaluate the feasibilities of concepts.

03

Prototype development

Develop a detailed plans and specifications for the chosen solution, and fabricate it.
This stage includes proposing a final prototype design, CAD and hands-on prototype development and fabrication.

04

Testing and evaluation

Evaluation of the design solution and identify any issues or areas for improvement.
This stage includes evaluation on the manufacturing process and a life-cycle assessment on the prototype to analyse the validity of the design's contribution to 'zero-waste'.
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Several biodegradable materials were explored, which includes cork and bio- polymer. However, the project finally arrived on Mycelium based bio-composite as the project direction after in-depth verdict of different materials. The attractive factor of this material is the up cycling of agricultural waste of agricultural waste into a bio-composite, which can be a key strategy to the idea of closed loop material flow highlighted in the 'zero-waste' philosophy.
The material has also been regarded as a highly valuable of interest to be research to be its novelty; very limited exploration has been done on the material properties and its application.

‍What is Mycelium based bio-composite?
Mycelium based bio composite is a bio-based material, fabricated by colonisation of filamentous fungi on solid organic substrates such as agricultural waste source (e.g., rice husks and hemp waste). During the growth phase, the fungal mycelium decomposes plant matter while progressively colonising the substrate, forming a three-dimensional mycelium network which perform as fibre and binder. The mycelium binder functions as a load transfer medium between the substrates, similar to the matrix phase of a polymer composite. The mycelium essentially acts as a 'natural glue' in contrast to the requirement of thermoplastic polymer bunders used in most medium density fibreboards (MDF) and particleboards. Mycelium-based bio-composite have several key benefits over conventional synthetic materials. This includes cost effective, density and energy consumption in addition to their biodegradability and low environment and carbon footprint.

The chronological order of the mycelium development is exhibit on above. The mycelium growth only started to be visible on day 2 due to its microscopic size during the early stages.

Material testing and analysis
Once the project direction was determined, preliminary investigation on the material was done, where small batches of the material were fabricated. This is subsequently followed by fabrication of material specimen for mechanical testing and analysis. These experimental results have suggested the mechanical performance and assisting in various furniture design considerations.

Material testing and analysis
The experimental result shows similar flexural modulus and densities with those of foams as shown in the material family chart Flexural modulus (GPa) vs Density (kg/m^3). The result suggested that the performance of the material was not as compelling as other wood material/ composites in flexure strength, which indicated that they are not suitable for load bearing application. However, this limitation can mitigate by furniture design in preventing bending/ flexing situation or higher material density.

Design phillosophy
The design brief stated that the furniture must satisfy all these 3 functions: clothes storage, toy storage, bookshelf.
To achieve this, the features was proposed to be access from 3 sides, in which the dimensions and accessibility to these features were also carefully considered according to the ergonomic study based on anthropometric data. This design promotes the Montessori method, which help children becomes more independent by taking ownership of their own spaces, through self-directed hands-on activity.
The mycelium-based composite is consisting of a white rot fungus, in which this species breaks down the lignin of the wood material. By using the unique trait of the material, where mycelium colonising and extending over the wooden material, the clothes hanging rail constructed using wooden dowel can be secured without the need of fasteners and adhesives.

Ergonomics and usability
The geometry of the furniture is built upon the ergonomic study established in Mini study 1, to ensure the design correspond to the children’s anthropometry and usability. Data from the experiment conducted has suggested that the material is not suitable for loadbearing at bending/flexure state. Hence, the design has been attempting to prevent the issue by avoiding beam system in the design and maximise material density.

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The Material
The material is comprised of sterilised hemp waste-fibres and mycelium spawn. The required amount was estimated by evaluating the volume determined from the CAD model generated. The overall volume was derived to be approximately 51.7 litres.

Growth and Incubation
The materials were added into a sterile bowl, followed by addition of flour and water for growth stimulation supplements due to the limited nutrition in the hemp waste. The mixture was stirred to ensure an evenly blended composition before adding into the mould.
The prototype was incubated in room environment conditions (~ 25℃) for 5 days before removal from the mould. The prototype was eventually dried in a convection oven at 70℃ until the until constant dry mass is obtained.

material in the mould during the growing phase

renders of the acrylic mould with 3D-printed Fasteners

Mould Design
The moulds are consisting of acrylic panels and 3d printed fasteners. Transparent panels were used for observation of mycelial development and the cut-outs on the panels allowed accessibility of air and preventing excessive moisture loss. A total of 32 acrylic panels with 6mm thickness was laser cut and fastened to form cavities for mycelium growth. Fasteners are designed to be easily removed when it is ready to be harvested.

Final prototype
The mouldability of the material, which cutting and trimming of standardised material is not necessary, implies minimum waste of material during the manufacturing process. The material is grown under ambient condition, wherein no energy was consumed during the growing process.

Life cycle assessment(LCA) and circular economy
Life cycle analysis were carried out to analyse the validity of current application’s contribution to ‘zero waste’. The end -product are fully natural and compostable wherein contributes to the transition towards circular economy, wherein the value of materials and resources is maintained in the economy for as long as possible.

Circular Economy
A possible scheme for circular economy was also devised to indicate how material flow in a circular model. The biodegradability of the material, which may consist of large amount of nutrients, has the potential of increase soil quality after composting.

Circular economy model devised for the current application.

The estimated energy consumption and CO2 emission for each element during the material acquisition stage.

The estimated energy consumption and CO2 emission for each element during the manufacturing stage.

Eco-Audit
The assessment was further developed by carrying out an eco-audit on the life- cycle of the product. This includes an estimation on the energy consumption and Carbon dioxide emission for transport, material acquisition and manufacturing process.