Prototyping
To test and evaluate the product, prototypes were made. To determine the dimensions, workings, and details of the product a low-fidelity prototype was made. When the shape and size was final a mid-fidelity prototype of a 1:1 size was created. This prototype was especially made for testing and evaluating the product.
Low-fidelity prototyping
When the concept idea was finalized a few steps still needed to be taken. Low-fidelity prototyping was used to determine the determine the dimensions of the product.
The materials used were:
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A bucket (12L, like the one Lisa has);
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Both hard and soft cardboard;
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Painters tape.
The cardboard was cut and bent to the desired shape and size. A few topics were brought up during this. For example, the width of the hooks. These were made quite wide in the prototype. This was not satisfactory, so it was decided to make the hooks thinner in the product.
Another topic was how the handle would fall on the seat. For most buckets the handle falls over the edge of the bucket. However, for this bucket the handle rests on the edge. Therefore, it was decided to make the cushion offset from the edge, to keep space for the handle.
After finishing the low-fidelity prototype, a test was done regarding walking with and holding the bucket. It was noticed that the bucket swayed a lot, to the point where it toppled easily. This would be a problem, especially when the attachment would carry more weight. Besides, the bucket had to be carried in a less comfortable way than normal, so the attachment did not hit the user. This can be seen in the pictures.
Following this test the prototype was altered slightly, so that the attachments sits at the end of the handle.This way the user can carry the bucket more comfortably and the attachments will not let the bucket topple as quickly.
Mid-fidelity prototyping
To further test and evaluate the product, a mid-fidelity prototype was made. The dimensions gotten from the low-fidelity prototyping were used to make a CAD-model of both the seat and the attachment.
To make sure the prototype would be able to hold enough weight, a simulation was done in SolidWorks. The details from this simulation can be found in the document. The conclusion is that the prototype would be able to hold at least 90kg, which is enough. It is important to note that this simulation does not include the strength of the bucket. It is only about the seat.
Realization
To realize the product, a workshop plan was made. This plan describes the materials needed and the step to make the prototype. The full plan can be seen in the document below. The most important materials that were used are:
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Plywood (seat)
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Cushioning foam (seat)
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Fabric (seat)
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3D printing filament (attachment)
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Sheet metal (hooks)
It was decided to make only one attachment for the bucket, because it would be more sustainable to do so. Besides, testing with only one attachment would be sufficient.
Final Prototype
Evaluation Realization
While in the workshop some complications were found. For example, the holes in the seat for the hooks seemed too small. Therefore, alterations on these holes were needed. A hand mill was used to carve out the holes and to fillet the inside corners of those, for aesthetic reasons.
At first the hooks were going to be 3D-printed. However, during the workshop we realized that 3D-printed hooks might not be as flexible as desired. Therefore, it was decided to make the hooks out of metal. In the end this was the right decision, because the metal bounces back nicely. The hooks are currently made by hand, which is not perfectly precise; However it was decided that this imperfection is acceptable for the prototype.
Choosing metal for the hooks made the hooks thinner. Therefore, deepening the holes of the seat was redundant.
Unfortunately, some materials were not available at the workshop. The seat in the final product is covered in plastic, to make sure the fabric does not get dirty. The plastic would make the product easier to clean. The idea for the prototype was to use transparent oilcloth, or another type of transparent, flexible plastic. However, the workshop did not have a material like this available. Therefore, the decision was made to exclude this from the prototype, because it is not crucial for testing. The plastic works in reusable sandwich bags, and is therefore a proved method to keep fabric clean.
Another material that was not available in the workshop was spray paint and fabric of the desired colors. Therefore, the prototype has different colors than the final product will have. It was decided to not buy extra fabric and paint because of financial and sustainability considerations. Buying the materials for a prototype would mean having a lot of left-overs, which does not fit in the vision of sustainable prototyping (which Lisa finds very important).
Lastly, an oversight that was made, was not taking into account the ends of the handle; These stick out. Therefore, the seat does not perfectly fit on the rim of the bucket. It does fit when the user would stretch the bucket a bit (which is not harmful), however, in the final product these handle stubs will be taken into account.
All in all, the prototype is satisfactory. It is sufficient for testing and evaluating, which is the goal of the prototype. The prototype was made sustainably, which is a value Lisa cares about. Furthermore, the prototype is strong and large enough to hold a person and tools. It's not perfect, however, its goal is testing and evaluating, which it is sufficient for. Therefore, the prototype can be used for the next and last step: Testing and evaluating.
Testing
To validate the list of requirements and check overal performance, usability and reveal areas for possible improvement, the product is tested. Due to limited energy and time of the case-owner, the product is tested by the group itself. This will closely resemble the actions and situations that the product will face when in use by the case-owner and can therefore be seen as a valid user test.
For the procedure used during testing, see linked PDF
1. Objective
What is being tested, and why? The purpose and expected outcome is also described. (See table)
2. Prototype Description
The prototype of the Versitool is a gardening tool meant to make gardening more energy efficient for people who may experience fatigue. The key functions of the prototype are carrying tools with a side compartment (meant to reduce the number of excessive movements to keep the tools with you), offer a comfortable seat on top which can also be used as a kneepad (meant to be a convenient way for taking short breaks and making activities more comfortable) and allow the user to put weeds in the gap left from the seat.
3. Test Environment
Testing will conduct outside of Horst tower at 11.00 am. Weather is sunny, 10˚C and not windy. The environment is calm with low noise level. Not a lot of people, cars and bikes. Equipment used is the designed product, props for garden tools, props for weeds, iPad and phone. Two group members will oversee the test and makes notes on an iPad.
4. Test Procedure
User experience: for testing all of the three user experience points, user should perform the necessary interactions and then provide feedback. Moreover some members of the group should be observing the user interactions and noting down the results.
Carrying tools: the group members should provide the user with prop tools to put in the attachment. The user is asked to garden* at a spot in the testing environment and then move to a different spot. *garden= pick up 4 props from the ground and place in bucket
Attachable and detachable within 10 seconds to a bucket: a user should detach and again attach the seat on top of the bucket, as well as the attachment, and the group members should observe and set a timer to measure, whether the action is being performed within 10 seconds. The group members should note down, whether the user placed the seat in a correct position, implying that they understand the design.
5. Measurement Criteria
User experience will be measured on user feedback and will be noted down by a group member.
Carrying tools will be measured on user feedback and will be noted down by a group member.
Attach and detach attachment will be measured on accuracy and efficiency and recorded by timer.
6. Participants
Case holder is not available, there for two UT students (19-21 years old) will conduct the test.
7. Expected vs. Actual Results
See table below
Overall, testing of the product went relatively sufficient. When it comes to user experience on easy use there was an issue with the user realizing that the seat can also be used as a kneepad. The function of the gap in the seat and the attachment for storage was clear.
The gap of the seat was clear. When seated, the gap was noticeable to the participant and it was clear that you can reach in and place weeds inside the bucket.
For portability without excessive strain the result was as expected. The participant claimed portability was a bit bothersome, but they recognised other the benefits of the bucket. This result can be said to be inconclusive of some sorts, because the participant did not have a lot of gardening experience, therefore was limited in strain to compare to.
Carrying the tools in the attachment went as expected. The participant placed the tools in the attachment and carried the bucket to the next spot. The attach- and detachability of the attachment and seat was not as expected. At first try it took the participant longer than 10 seconds to attach and detach the attachment properly. This was due confusion of placement of the bucket’s handle and order of placing the seat and attachment in. After trying it out once, the process of attaching and detaching became quick within 10 seconds.
8. Limitations & Assumptions:
Results may differ due limitations and assumption that taken during testing. The test participants are not the case holder or the users with similar conditions. Assumed is that the participants know how to garden.
The test environment is not a garden. Garden tools and weeds uses are not real, but props are used. Assumed is that the props weigh similar to garden tools.
Number of participants are limited which influence the overall results. Participants are UT student who know are aware of the project and the designed product itself.
