Usability test for microwave

Introduction

Usability test is required for almost all products before they are put into production, for it can help collect practical feedback and reflect how real users feel about the products. Nonetheless, running usability test to existing products is also important, since it helps designers learn from existing products and gain experience. The usability test we run is about the extent to which the microwave can be used by specified users (students in this case) to complete specified tasks(heating and cleaning) with effectiveness, efficiency and satisfaction in a specified context of use (daily life).

  • Stakes: Running a usability test involves real users using the products and can help designers receive practical feedback and reflect on the products.
  • Target product: The microwave at Lander Hall. GE Household Microwave Oven. Model Number: PEB1590SM2SS.
Interface of the microwave
  • Participants: One male and two female, 18–22 years old, who are highly related with the products
  • Tasks: 1.Popcorn making 2.Removing and inserting microwave tray 3.Setting exact time and power level of the microwave
  • Data collected: 1.Frustration level when completing the tasks 2.Time spent to complete the tasks 3.steps taken to complete the tasks

Process of the usability test

Users were firstly asked a couple questions about their backgrounds, specifically about their previous experiences with microwave. Two user rarely use microwave while one user uses it frequently.

Before every task, the moderator read an instruction about the task in order to explain the study, dissociate the users, provide scenarios and encourage users to talk through the task.

The instruction can help users know more about the tasks, be more cooperative and more natural when doing the tasks

During the three tasks of three users, the time and steps taken by users to complete the tasks were recorded.

Users doing three tasks
Time taken to complete the three tasks
Steps taken to finish the three tasks

In the first task, if users used the “popcorn” button, the efficiency would be much higher than if they used the time knob. However, the product did not correctly guide every user to use this feature.

In the second task, all users finished their tasks in less than half minutes. Compared to other products, this one has a good design of physical restrictions in helping users clean the tray.

In the third task, data shows that this product is easy to use for experienced users, but hard to use for new users.

After every task, users were asked a question about their frustration levels with the products, scaling from 1 to 5, when 1 stands for no frustration and 5 stands for extremely frustrating.

Frustration levels of three users

Further details are in the presentation:

https://drive.google.com/a/uw.edu/file/d/0B0Mo-mNRmxgDVklkX0tGa1BsaVE/view?usp=sharing

The link to a video explaining the presentation:

Problems met and places that we can improve:

  1. During the test, although being separated, all three users stayed in the same room, and this situation led to the mutual influence among users: users who were waiting might hear information, which influenced their efficiency and steps taken later, and made the usability test less accurate. We should have let users come in separate times to avoid the mutual influence.
  2. In the second task “Removing and inserting the tray”, due to the fact that the tray was heated in the first task “Popcorn making”, the tray was hot and made users feel a bit uncomfortable. The temperature issue might led to the changes in time taken and steps taken. We should have rearranged the sequence of tasks, making the second task first, and prevented users from getting burned.
  3. After users finished the first task “Popcorn making”, they had more knowledge about the microwave, therefore in the third task “Setting exact time and power level” they interacted with the microwave with more fluency and less frustration. This overlap between tasks made our data less accurate. We should pick another feature to test, which has less influence with other tasks.
  4. Though the specified users of the usability test are mostly students and our users are highly related to this kind of users, the sample of participants is not diverse enough. We should have users with more varied backgrounds.

Useful and interesting things about this project:

This project reveals lots of problems not only of this model of microwave, but also of most models of microwaves on the market. These products have many features but ignore the usability. The target product of this test have sixteen buttons standing for different features, but most of them do not help but confuse the users. For example, features like “Popcorn” and “Cook” can actually be accomplished by using the “time cook” and “power level” buttons, which provide users with more than one option and confuse them. Despite the fact that microwave was invented decades ago, the usability is still a problem, which circumstance exposes that numerous products in people’s daily life still need to be improved on usability.