Mandoline Slicer Redesign
An ergonomic redesign of a kitchen mandoline slicer handle
Introduction
Role
Designer, Researcher
Timeline
5 weeks
Class
Product Design Methods
Team
Jalil Cooper
Khuyen Nguyen
For our Product Design Methods class, my team was tasked with re-designing a handheld tool. We opted to redesign a kitchen mandoline slicer to ensure accessibility and safety.
Tool
Autodesk Fusion 360
The Challenge
The current design of the kitchen mandoline slicer handle does not allow for a comfortable and sturdy grip, as well as ensuring distance from blade for user safety
How can our re-design ensure user comfortability and safety when using or handling the tool?
Initial Research
Design Requirements
Design Exploration
Final CAD Rendering
This is a project where we did extensive user testing and interactions, so although I’m not much of a physical designer myself, I’m excited to apply what I’ve learned to my other projects!
I also plan to refine the design, especially by adding a base to the model so reflect an actual slicer and not just the handle.
In my initial research, I was tasked with finding a handheld tool to redesign. I chose a mandoline slicer, a kitchen tool with an adjustable blade, allowing for precise and efficient slicing of fruits and vegetables.
I chose this tool because the slicer was infamous around the house I was living in for causing injuries among our residents.
I was curious to see why. To investigate the issue, I analyzed the tool using force analysis and a hierarchical task analysis.
Prototyping & Initial Testing
Refined Design Focus
Final Design
Final CAD
What’s Next
After analyzing the tool, we found that we wanted to focus on:
The grip of the handle
Removing pressure from arm and wrist
Distance from blade to prevent injuries
Our focus led us to our 6 design requirements:
Significant vertical distance from hand to blade to prevent accidental injuries.
Comfortable grip diameter to lessen the load on wrist and provide comfort for long usage periods
Anti-slip grip
Shift load from wrist/hand to forearm and shoulder when driving slicing movements
Comfortable thumb rest
Sturdy enough to withstand applied forces from hand load
Based on the design requirements, each of us came up with 10 sketches on how we can re-envision the handle
Based on my sketches, I created foam models and recruited users to test them.
I chose my test them with 3 of my housemates with different hand sizes who were familiar with the mandoline tool originally.
We tested them out using testimonials as well as the RULA (Rapid Upper Limb Assessment) test to assess the effect of our model on a user’s upper body while using our product.
Our initial research shows that:
Users found that their thumb was placed awkwardly
Users wanted a further distance from the handle to the blade for safety
After the last iteration, we focused on two criterias for our prototypes: thumb groove position and grip distance.
Based on our testing with users with varied hand sizes, our findings can be summarized as:
Offering a side and top thumb placement caters to a wider group of users:
“I like that you are able to rotate the handle and use it at different angles”
A shortfall of the top thumb position is that it is not suitable for users with a larger palm since their thumb would overextend over the dedicated thumb slot:
“Because I’m double jointed, my thumb overextends a bit so there’s pressure coming down on my thumb joint”
Opting for a medium height handle length (4-5”) offers balance between providing safety from blade & precise slicing
For longer handles, people felt safer from the blade but users experienced wrist strain:“I feel like my wrist isn’t supported due to the length but it provides a good distance from the blade”
Based on the feedback, we created new sketches and models to explore the design changes. We then tested the foam models with our user group.
Three final foam models
Based on our user feedback, we decided to combine our designs that have thumb groves and one that would provide a good safe distance from the blade.
