Heating Pad Control

Developed a fresh take on a common appliance through innovative concept ideation based on research, design principles, and selective framing.

Project Overview

Propose a new design for a heating pad control that takes into account different use cases along with the basic requirements and attributes of the physical control itself.

Duration

2 weeks

Role

Product Design, Concept Ideation, Primary & Secondary Research, Usability Testing, Presentation Execution, Lo-Fi & Hi-Fi Prototyping

Process

Exploration

Brainstorm

My process kicked off with several brainstorming sessions to identify current knowledge and working assumptions about the intended use case, requirements, and form of a heating pad control.
After identifying common conventions, it was fun to delve into alternative opportunities a heating pad may afford for activities like fermenting yeast or warming sourdough starter.
This led to a sketching exercise to explore how the contexts and requirements identified might influence the physical form.
Benchmark Analysis

By conducting a benchmark analysis, my goal was to understand the conceptual models that currently exist for heating pad users based on trends in design and functionality.
I identified key characteristics in heating pad controls as well as analogous products such as thermostats and light timers to document a broad range of opportunities.
I paid specific attention to what functions were present on the face of the control as well as the mapping of said functions and the feedback signals they produce.
Key Takeaways

• Simplified, clear controls - most include identifying information directly on the button to indicate function, whether with a symbol or text, but few offered raised buttons to allow recognition through touch alone
• Similar buttons were present (power, up, down, timer) and there were trends in mapping
• None allow you to type in the exact temperature you want, the majority of options only offer subjective heat settings (warm, low, medium, high) or + and - buttons to adjust incrementally
• Most are ergonomically designed and allow for comfortable grip
• All controls were directly attached to the heating pad via cord and could not be removed to monitor at a distance
• Some feedback indicators included lights for power and/or heat level and beeping when buttons are pressed
• Majority include automatic shut off function
• Some come equipped with a digital screen, but none were back-lit to afford optimal use in low-light settings
• Few include app integration

Ideation

Concept Development

After synthesizing the information from my benchmark analysis and reflecting upon my own interactions with a heating pad control, there were myriad characteristics I knew I wanted to address in my design.

Most notably, I did not set out to reinvent the wheel. My intention was to expand upon existing forms to make the control more efficient and enjoyable to interact with.

With the user in mind, I didn’t want to divert too much from current models in terms of layout and functionality. I felt it was important to take into account external consistency in established conventions and industry standards to improve discoverability and ultimately, allow for a pleasant experience.

I became focused on the opportunities for mobility and stability. I was interested in exploring ways to monitor and manipulate the control from a distance, either for yourself as the direct user or as a caregiver responsible for elderly relatives, children, pets; or patients in a hospital, rehab, or nursing home setting.

This led to the consideration of dual control and screen mirroring to ensure both parties had agency and could control the device while being informed of the others’ actions.

Early Design Decisions

Large, raised buttons that communicate their function through touch alone to allow the user to operate without looking
Multi-sensory feedback that includes a combination of lights, sounds, or screen display
Screen display should be backlit to allow for ease of use in low light settings
Design something that affords control from a distance - whether by app or detachable piece
Ergonomic design that fits comfortably in hand and allows for one-handed control that is equally usable for both left and right-handed users
Explore the idea of presets for routine use cases
Avoid ambiguity and subjectivity in heat settings - stay away from terms like “warm, medium, hot” for temperature

Design Principles Framing

To hone initial concepts and push designs further, my next step was to explore how the design could be tailored for a specific design principle. By making design decisions based on the requirements of one principle, I discovered new ideas and it streamlined my decision-making.

It was particularly helpful to watch similarities emerge across sketches for different principles. By recognizing these recurring ideas, I was able to identify which features served multiple principles and would ultimately be the most beneficial to incorporate in the design.

This led to more sketching…

Users & Use Case

The next step in my process was to frame my decision decisions around specific users and contexts. There were several clear directions that I imagined I could go using the same general form. This exercise brought me closer to realizing what my solution would be and how best it would fit the user I was designing for.

The Routine User

This design involves a higher level of complexity. It is ideal for a direct user who frequently finds themselves reaching for their heating pad:
• A combination of both analog and digital controls
• Backlit screen for low-light use
• Several configurations for holding and hanging with comfortable grip
• Ability to monitor and adjust from a distance using the detachable control
• Ability to set presets based on recurring use case ( (i.e., back, neck, knee, etc.)
The Caregiver

This design lends itself more towards an indirect user. This person wants to be able to control and monitor the heating pad from a distance.
Whether it be a granddaughter taking care of a grandmother or a nurse caring for a patient, this option includes additional bells and whistles to ensure the caregiver is kept informed on the status of the heating pad at all times:
• Lights up and beeps when set temperature has been reached and when the temperature begins to increase or decrease
• Ability to set a child lock so the pad can only be controlled from the detachable control
• Ability to set a min/max range of temp
• Monitors both temperature of the pad and temperature of the skin
• Walkie-talkie function between devices
The Minimalist

This design is the baseline option for those who are not technologically savvy and only need to use a heating pad for its basic functions:
• Several configurations for holding/ hanging with a comfortable grip
• There is no detachable control as with other designs, instead, that void affords the opportunity to either hold onto or hang the control
• Backlit screen for low-light use
• Clear, distinct buttons that can be operated without looking at the control

Persona

By exploring different designs through the lens of specific users, I identified the persona I was designing for and the functionality they needed in a heating pad control:

Prototype v1

Refinement

Learnings & Adjustments

Upon completion of my prototype, I noticed two things. The first is that the overload of functions and feedback signals on the face of the control made the design feel a bit chaotic and aesthetically overwhelming. This is not the feeling I was hoping to convey, so it was clear I needed to dial it back and lean into a more minimalist design to achieve a sense of ease and calm.

The second thing I was struck by was the shape of the control was not comfortable in my hand. My intention was to create something the user wanted to hold because of how natural it felt.

It also brought up questions around accessibility, particularly with regards to the detachable control. An elderly user or someone with arthritis might struggle to finagle the piece in and out of the tethered control and create unnecessary frustration. I needed to reconsider how these two pieces interacted.

Critique & Feedback

I also shared my physical prototype with peers and professors for feedback and critique, which brought up additional improvements to consider and questions to address.

Overall, it was clear that some of the feedback signals were redundant. It was not necessary to utilize both lights and messages on the screen to communicate the same message.

In addition, some elements didn’t align with the proposed functionality; specifically, the power button on the detachable control. If the power button lives on the touchscreen, how then would a user power it on when the screen is off?

I also needed to figure out exactly how the user would control time vs. temperature. Initially, I proposed including an attachment on the side of the device, similar to a light timer, but this idea led to a conversation about the importance of consistency with conventions. If the time is set with a different control, it should not require the user to learn a new paradigm.

Further, if the same buttons were to be used to control both temperature and time, I needed to make that distinction extremely clear for the user.

This reflection led to experimentation with a new form:

Prototype v2

Solution

In this second version of my design, I made sure the form of the control was comfortable to hold in one’s hand and naturally rested in the palm. I achieved this by carving a block of foam and repeatedly testing it.

I also adjusted the proportion of the detachable control in relation to the tethered control by scaling it down. I wanted the hierarchy between the two objects to be clearly communicated through the design. The tethered control is meant to be the prominent point of interaction as it is capable of increased functionality and has an attached power source. The detachable control is meant for moments when the user needs to step away and be physically apart from the heating pad.

I continued to prioritize the importance of being able to operate the basic functions of the control without looking at it. Each button has a raised element that communicates its function, affording discoverability through both sight and touch.

I also kept the suction cup on the back of the detachable control to promote mobility and stability. The suction cup is strong enough to hold the detachable control on its own or the full control as a whole. The latter is relevant for moments when the user wants to keep the control in sight while using the heating pad. The potential for the control to get lost under other blankets, pillows, etc. was a consideration I wanted to account for.

To address my concerns about accessibility, I adjusted the interaction between the two controls. In my first concept, the user had to fit the detachable control into a void within the tethered control. In this version, they click together with strong magnets to allow for a seamless, low-effort, on and off motion.

I also considered how to ensure equal accessibility for both right and left-handed users. I tested this shape and size in both hands and achieved the same ease of motion when in each orientation. I also mapped the temperature buttons in the center as those would be the most interacted with during use.

Preset Functionality

Setting and activating presets is perhaps the most complex functionality to define. Two design principles were key to my process when determining the preset functionality: feedback and error prevention.

An overarching principle for the design as a whole was for the screen to immediately reflect what the user was doing, and that’s true in the case of setting presets as well. What’s not shown in this storyboard is the feedback that is communicated through the movement of the elements on the screen. When you go through the flow of setting a preset, the information that has yet to be confirmed (either time and/or temperature) will be blinking until it has been set. Once it has been set, the corresponding numbers will be static.

Further, I took error prevention into consideration by including a two-step process when activating a preset. The user must press the button to select the preset they want to activate and then press it again to confirm their choice. Once the preset has been activated, a small icon will appear on the screen and the temperature will begin to heat up. As soon as the target temperature has been reached, the timer will begin to count down.

Reflection

Overall, I enjoyed this process and feel good about my final concept. I was pleasantly surprised by the innovative design considerations that can be made for a heating pad control.

I found value in the methods employed to address the design from specific angles, specifically through the lens of isolated design principles and users. The act of framing for a specific principle or user definitely pushed my thinking and evolved my concept. I uncovered new options for form and function that ultimately made the design more successful. This method was particularly helpful in moments I felt stuck and unable to make decisions. Zooming into specific frames can limit options in a favorable way and catalyze thoughtful decision-making.

One thing I would do differently would be to spend more time testing options for the mapping of the functions on the face of the control. I committed to my layout early on in the process, only to realize afterward that had I made a few small tweaks, it would have proven to be more successful. To avoid this in the future, I plan to cut out shapes for each button and arrange them in different configurations until I find the best fit.

As you can see in the image on the right, I ended up revisiting my design after my presentation to adjust the mapping. I moved the power button to the side of the control to free up some space on the face while keeping similar functions close together.