RICHARD ZHANG
Design Engineer Imperial College London
DESIGN TASK
We were briefed to design a battery powered hand tool for an under served user group. Over the course of six months, we researched the needs of night shift workers to design a new drill which would accommodate to their unmet needs.
OVERVIEW
Our team initially selected night shift workers as an under-served user group to target. We carried out both ethnographic and statistical analysis on the matter to build up an understanding. Anonymous data was taken in via in-person interviews with night workers on the job around central London as well as online surveys.
After our initial research, we narrowed our scope onto designing a new drill for night shift construction workers. Our research had provided three key insights that we wished to address and each member of the team developed a concept hand drill to address these insights. Our peers then voted on which features from these concepts to implement on our final prototype.
After several weeks of building and user testing, we presented out our final prototype, a self-assembly drill made from natural materials. Built in to the drill is a circadian light that stays on after a job is complete and shines through the casing of the drill. A new, larger capacity battery was added that can be connected to the drill via a magnetic trailing cable for more versatile use.
FINAL
PROTOTYPE
The team's final prototype was a self assembly drill which featured a circadian light which shines through the body of the drill and stays on for an extended time after the drill is used. A larger capacity battery was implemented which could be attached traditionally or connected via a magnetic trailing cord.
The self assembly nature of the drill was implemented to create a stronger sense of attachment between user and tool. New components had to be designed to allow the user to assembly the electronics of the drill without having to do any soldering.
The circadian light aids in keeping workers awake at night. We found that in some sectors accident rates could double at night and this increased rate was attributed to fatigue.
Battery capacity was increased without impacting the ergonomics of the drill by giving the option to rest the heavier battery on the floor or a tool belt while power is carried through a magnetically attached cable. Multiple tests had been carried out to ensure the drill was properly balanced in both configuratuions.
MY
CONTRIBUTION
Throughout the build my focus was put onto electronics and manufacture. Initially, this consisted of creating test rigs to find power consumption of a regular drill use and selecting a new battery and components to bring the prototype drill up to its new higher specified battery life.
I designed an analog timer circuit to keep the circadian light on after the drill was used. The circuit sits inside the housing of the drill and is activated when the trigger of the drill is pulled.
I also developed the contacts that go between the battery, cable and drill. These are sprung loaded copper contacts which are designed to only be put on in one orientation.
I assisted my colleagues in printing the casing which we had designed on both FDM and SLA printers. This extended to the post processing of prints and final assembly.
THREE KEY
INSIGHTS
Of all the information we collected within the initial research phase, the team pointed out three insights that were particularly interesting. The first being that, biologically, humans are not made to be awake at night. Our circadian rhythm is disrupted and leads to a multitude of both physical and mental health complications. In addition to this, the lack of supporting infrastructure can make tasks as simple as finding a hot meal and getting home a stressful ordeal. The amount of human interaction decreases and leaves night workers feeling isolated.
Secondly, there is a desire for drills to have a larger battery life while remaining light and easy to work with. Workers were regularly frustrated by interruptions to their jobs and carrying multiple batteries was another point of frustration. Simply increasing battery capacity would not be a complete solution due to increased weight and poor ergonomics.
Thirdly, workers develop emotional attachments to their tools. This human behavior is most notably seen in soldiers personifying their EOD robots, going as far as to hold funerals for them when they break. The team decided that this behavior could be positively modified, with evidence of such emotional attachments having beneficial effects regarding stress and work ethic.
CONCEPT DEVELOPMENT
The team proceeded to use all of our findings to create low fidelity concepts. My proposed solution was a modular drill and impact driver that could switch out heads and attachments for variable battery life, weight and function. We then pitched our concepts to peers for them to voted on aspects from different concepts to be used in a final prototype.
