Step Counting Cane

our team designed and developed a modular, adjustable cane intended to encourage physical activity in elderly users. The cane includes a mechanical step counter and an adjustable-length mechanism. Each component was either modeled in CAD or sourced as a COTS (commercial off-the-shelf) item.

The handle, hinge, and connecting pin were 3D printed to prototype the most mechanically critical parts—these form the core adjustable joint of the cane, allowing for ergonomic movement and height customization. We chose to prototype these first due to their mechanical importance and the higher risk of tolerance and fit issues.

For our adjustable cane project, we utilized a combination of 3D-printed components and commercially available off-the-shelf (COTS) parts. The 3D-printed parts included the handle (printed in PLA, 35 grams, 20% infill), the hinge (PLA, 25 grams, 20% infill), and a 3D insert (PLA, 2.74 grams), all printed in a horizontal orientation to ensure structural integrity and print consistency. These parts were chosen for prototyping due to their critical mechanical roles and the potential for fit and tolerance issues that needed to be tested early.

The COTS components consisted of two 1/4"-20 bolts (1.75" length, steel), two standard steel nuts, and one 5/16"-18 flange nut, all purchased from Lowe’s. A threaded knob (steel) was also sourced from Lowe’s to serve as the locking mechanism for the adjustable tubing. For tracking steps, we integrated a chrome-plated pitch counter sourced from Target. The cane structure included an upper aluminum tube (1" x 1" x 18") and a lower aluminum tube (¾" x ¾" x 24"), both selected to accommodate users of various heights. Finally, we attached a rubber foot (1" diameter, 1.75" height) from Lowe’s to the bottom of the lower tube to ensure floor grip and user safety.

This combination of parts ensured functionality, manufacturability, and user-centered design, while keeping material sourcing cost-effective and accessible.

1. 3D Print Custom Components
2. Print the handle, hinge, and 3D insert using PLA filament with 20% infill.
3. Use a horizontal print orientation for strength and dimensional accuracy.
4. Verify dimensions post-printing and lightly sand or adjust any areas for improved fit.

Gather all bolts, nuts, flange nut, and knob from hardware suppliers.

Cut the aluminum tubing (1" x 1" and ¾" x ¾") to lengths of 18" and 24" respectively, if not pre-cut.

Ensure all aluminum tubing edges are deburred for safety and proper assembly.

Acquire the rubber foot and pitch counter (if needed, disassemble the casing to prepare for integration).

Align the handle and hinge components at their connecting slots.

Insert the 3D-printed pin through the aligned holes to connect them.

Secure the pin in place using nuts and bolts, ensuring free rotation with minimal friction.

Slot the handle’s hinge portion onto the top of the upper aluminum tube.

Insert the bolt and flange nut through the aligned holes to secure the handle.

Tighten appropriately while maintaining desired pivot motion.

Fit the 3D insert into the bottom of the upper aluminum tube.

Slide the lower aluminum tube over the insert to ensure a snug telescoping fit.

Use the threaded knob to lock the insert and lower tube together at the desired height.

Fix the pitch counter to the front flat face of the handle or tube using double-sided tape, epoxy, or a mechanical mount.

Ensure the reset knob and push rod are accessible and aligned for user operation.

Press-fit or stretch the rubber foot onto the bottom of the lower aluminum tube.

Ensure it fits snugly to provide traction and protect the cane from slipping.

Test all mechanical joints for ease of motion and secure locking.

Ensure the height adjustment functions smoothly and the step counter operates as intended.

Check for loose fasteners and make any necessary tightening or adjustments.