Jenny Hegelein
industrial design | project management
Main Features
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4-way ergonomic grips
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Adjustable reach
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Improved user safety
Injection molded plastic & silicone over molding
Dimensions in mm
Ergonomic Hazards of Current Ratchets
Mechanics use both pneumatic and electric ratchets to loosen or tighten bolts while servicing vehicles
3/8" pneumatic ratchet, first & second fingers on trigger
Due to the linear design and
trigger location, ratchets are limited to one type of grip
Industry Standard Example:
Milwaukee M12 Extended Reach Ratchet
Since the bolts are in small hard to reach places, mechanics have to twist their arms, wrists, and back in unnatural positions to use the tool.
Mechanic servicing engine bay
Most Common Grips & Reaches
I observed the users holding the current ratchets with unnatural arm positions and wrists bent in an extreme degree of motion.
A ratchet with adjustable angles will allow the mechanic to
bend the tool, not their wrist
Up & Over​
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Vehicle is on the floor
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Bolt is located above chest level
Under & Up​
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Vehicle is on a lift
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Bolt is located below chest level
Carpal tunnel is the compression of the median nerve due to strain and repetitive wrist movements, causing pain and numbness
To avoid injuries such as carpal tunnel, the wrist needs to be in a straight, neutral position.
56% of illnesses reported to the Occupational Safety and Health Administration are ergonomic disorders
20% of reported injuries by mechanics were caused by repetitive trauma
-The Bureau of
Labor Statistics
Conclusion:
A ratchet that allows neutral wrist positions will improve safety conditions for the mechanic
Round 1:
Symmetric Design
for ambidextrous grip
Common Grip #1
held w/ pivot on top
(Up & Over use case)
Common Grip #2
held w/ pivot on bottom
(Under & Up use case)
Round 2:
Linear Profile Adjustments:
Unnecessary bulk removed to better fit in tight spaces
"X" Design still doesn't clearly corelate with grip, still needs refinement
Round 3:
Enhanced Contours
for stronger grip
Improved Use of Color
to signify intended grip
Round 4:
Along with the grip models, users also tested a mockup of the angle adjustment for proof of concept.
The RatchAdapt
Grip Features: 4 Ways to Hold
1
Common Grip #1
(Up & Over)
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Vehicle is on the floor
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Bolt is located above chest level
Left-Handed
Right-Handed
3
4
2
Common Grip #2
(Under & Up)
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Vehicle is on a lift
-
Bolt is located below chest level
User Safety Improved by:
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Ergonomic shape increases grip strength, improving control over the tool
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Unique design and trigger placement allow tool to be held 2 different ways to cater to wrist neutrality
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User needed a slim design: tool fits into the tight spaces needed to prevent crushing or pinning their hand against hot or sharp metal
Adjustment Features
Press side buttons in to release pivot lock
Pushing in on both sides prevents accidently releasing the ratchet angle while in use
Angle adjustment to
bend the tool, not the wrists
Assembly Features
