Capacitive Extendable Pointer

Capacitive touch technology is very common today, especially in a kitchen setting. For people with a smaller stature or limited reach, accessing the controls to these technologies can be difficult. Conventional extension pointers won't work because they can't mimic the capacitance of a hand.

This Instructable documents the process of modifying a conventional aluminum pointer into one that can mimic capacitive touch and therefore work with capacitive technology. This device was designed as part of the MIT class Principles and Practices of Assistive Technology (PPAT). The original client uses this device to access her oven controls, which are behind the stove burners, without risk of getting burnt.

Steps 1-4 describe how to assemble the new capacitive extendable pointer. In short, this includes removing the felt tip, creating a new base for the silicone tip, and finally securing the new silicone tip.

Below is the documentation of the bill of materials for this project.

Step 1: Remove the Felt Tip

The felt tip that comes with the Telescoping Teacher's Pointer is the only part of the design that is preventing the capacitance from travelling from the hand to the tip. Therefore, the tip has to be removed and replaced with a capacitive counterpart. The tip itself is easy to remove and can be done by rotating the tip with your hands until it comes out.

Step 2: Prepare Two Pieces of Aluminum Foil

These aluminum foil pieces will be used to support the silicone tip we will later install and prevent them from sliding to the bottom of the tip holder.

2a. Cut a 1''x12'' strip of aluminum foil.

2b. Fold this piece in half.

2c. Cut the aluminum foil piece in half.

2d. Roll these pieces along the long side until you have two short stubs of aluminum foil.

The final pieces should be around 1/2'' tall.

Step 3: Press the Aluminum Foil Pieces Into the Felt Tip Holder

Using the pen/pencil, press the aluminum foil pieces into the felt tip holder until the upper surface is compact. There should be about 1/16'' distance between the top of the felt tip holder and the aluminum foil surface. If there are gaps in the aluminum foil or the surface is not 1/16'' away from the top, add extra aluminum pieces using the same method outlined in Step 2.

Step 4: Glue the Silicone Tip

Using the Crazy Glue, apply a small amount of adhesive to the rim of the silicone tip and press it firmly into the tip holder. Allow to set for at least 2 minutes. Test to make sure the tip doesn't move when applying pressure. If it does, add another layer of glue around the outside.