The Sensor Handle:
Measuring Walker Weight
Fueled with M&Ms, our class brainstormed different ideas and ways to quantify upper extremity weight bearing on walkers. We thought about using weight sensors and attaching them to different parts of the walker or even to the user.
We thought about embedding the sensor into the wheels or handles of the walker. We also thought about placing weight sensors into the shoes of the user to measure their weight.
Our team narrowed our ideas down to the following: placing sensors on top of the walker handles, creating gloves with sensors embedded into the palm, and attaching the visual display to the front of the walker.
We divided our design into two components:
• The visual display to show upper extremity weightbearing in real time
• The sensors that measure the weight borne onto the walker
In our mock-ups, we wanted to learn the ideal location for the visual display and where the sensors should go. To do this, we created three mockups shown below.
Visual display placement:
Determine if the the user can clearly see digits in the display and the best location and tilt angle to attach the display on the walker
Testing for location:
• Attached the display in 3 different position on the front of the walker:
• Center
• Left of the center
• Right of the center
• Asked the user to use the walker as he normally would and try to watch
the digits in the display
• Asked him to rank the location based on his preference
Testing for tilt angle:
• Placed display in the user’s preferred location
• Tilted the display to several angles
• Asked user to rank tilt angles based on preference
User preferred location at the center of the walker with a 40˚ upward tilt
Sensor in the handle:
Determine if the sensor in the handle is comfortable to the user and interferes with therapy
• Placed sensor on top of handles of the walker
• Asked user to use the walker normally
• Asked him to rate comfort levels and whether it interferes with
therapy
User said the sensor and handles were too big to grip and were uncomfortable - perhabs embed the sensor into the handles
Sensor in gloves:
Determine if gloves with embedded sensors are comfortable to the user and interferes with therapy
• Asked user to put gloves on
• Asked user to press hand with glove onto table and rate comfort
• Asked user to use walker normally with gloves and to rate comfort and
therapy interference
Sensor was painful to press on and hands were sweaty and uncomfortable within glove; client was worried about loose wires
Mockup Testing Conclusions:
• Eliminate sensor in glove design - too painful and uncomfortable
• Keep wires hidden so that they don't interfere with therapy
• Embedding sensor in the handle could be an option – must create a separate handle to
be attached on top of the handles of the walker
We presented sketches of our latest design solution to our class, professors, and prototyping shop staff. Our design included a handle with an embedded sensor attached to each handle of the walker.
Sketch of handle with embedded sensor attachment
Sketch of handle with embedded sensor attached
to walker
• Implement a crossbar to between the handles to stabilize the apparatus
• Visual display can be located on the crossbar
