Design of Exchangeable Tips for White Canes for Visually Impaired People

According to data from the World Health Organization, there are at least 2.2 billion people in the world with impaired near or distant vision. The Population and Housing Census conducted in Mexico in 2020 reports that activities such as walking and going up or down stairs are the ones that represent the greatest difficulty for people with disabilities. The different surfaces that we find in our day to day can become a barrier or difficulty for people with visual disabilities who use a white cane. This technical help is an orientation and mobility instrument for these users, which allows them to detect, avoid obstacles and serves as an identification element so that the rest of the people can notice the presence of a visually impaired person. Regarding the tips of the canes, their importance lies in the fact that they are the part that makes contact with the surface when walking; determining the optimal tip of a white cane depends on a number of factors, including the environment in which it will be used, the user's preference for the type and amount of feedback, and the technique to be used, whether it be two-point touch or constant contact. This project presents the design of five cane tips, each one for a different surface: floor, cobblestone, sand, gravel, and grass.

The materials needed to use each of the tips are listed below.

For all tips you need:

• 3D printer
• PLA filament

For the floor tip:

• A bearing 5x15x5 (mm)
• A M5 Screw with 50 mm length
• A M5 nut
• .stl named Half_Marshmallow_Rolling
• .stl named Marshmallow_Tip

For the cobblestone:

• A 50 mm diameter rubber tire with a width of 20 mm that has a rim of 10 mm diameter and a height of 38 mm.
• 4 M3 Screws
• .stl named Free_Wheeling_Tip

For the sand tip:

• .stl named Bowl_Tip

For the gravel tip:

• .stl named Claw_Tip

For the grass tip:

• 1 Bearings 5x15x5 (mm)
• 5 M3 screw with 30 mm length
• 5 M3 nuts
• .stl named Half_Roller
• .stl named Clamp_Roller
• .stl named Roller_Bow

All the .STL mentioned are in this section

Mentioned below are the recommendations for printing tips.

1. Download all the .stl files listed in the materials section.

Following in this section are the steps to adjust the tips to the white cane. For sand and gravel tips no further steps are needed after printing and removing supports.

1. Position the bearing into its position on the first half of the roller.
2. Place the half of the roller in the position as shown in the image, entering the thinner tube of the arch through the internal diameter of the bearing.
3. Join the second half of the roller to the first, place the screws in the indicated positions and place the nut to secure the union to the ends.
4. Connect the clamp to the roller arch with an M3 screw.
5. The head or base of the clamp connects to the pole.

1. Locate M5 screw inside the first half of the rolling tip.
2. Insert the bearing in the position indicated in the image through the aforementioned screw.
3. Join the base of the tip through the screw, place a nut on the inside of this base, which will be inside the cane.

1. Place the rim of the tire inside the corresponding frame on the base.
2. Place and adjust the screws inside the place indicated in the figure to fasten the rim of the tire.