Improved Wrist Rests for Typing

Many people nowadays spend a lot of time in front of a computer every day, which can result in wrist pain. My mom is one example. Even though she's tried tons of different types of wrist pads for keyboards and mice, she still complains about wrist pain from time to time. I wanted to help her alleviate this pain by improving her wrist rests. I first observed the problems and drafted some possible solutions:

1. Mobility. She does a lot of typing in her line of work, so her hands move around the keyboard and mouse a lot. Since her right hand has to constantly switch between the keyboard and the mouse, it is almost impossible for her wrist to always be supported by any stationary wrist pad. 

One possible solution is to have the mouse built into the keyboard, as in a trackpad or trackpoint. But this is a huge change, as most people prefer using mice.

An alternative solution is to build a mouse pad that stays with you as you move your hands around. As such, we added roller ball caster wheels to the bottom of the mouse pad. We also decided to make one mouse pad for each wrist to allow more freedom in movement.

Making two individual mouse pads also solves another problem. When your hands rest on a keyboard, your arms are not parallel-they angle in towards each other. This is why some people prefer split keyboards. Most wrist pads are long rectangles intended to fit both wrists, which prevents you from naturally angling your arms.

2. Ergonomic support. When your hands rest on a keyboard, in addition to the previously mentioned inwards tilt, your wrists will rotate. Your thumbs naturally rotate upwards, while your pinkies rotate downwards. A ergonomically designed keyboard will have a typing surface tilted in the same way. However, some wrist pads are flat, which means that they don't properly support the wrist.

This means we need our wrist support to slope upwards and preferably fit the shape of your wrist.

With a little more digging, I found that there are deeper problems not resolvable by just a mouse pad. This mouse pad will help your wrists be more comfortable, but to make your spine, arms, neck, etc. comfortable you will have to adjust your desk, monitor, and chair.

3. Height customization. We want our wrist pad to be usable by everyone. Since everyone has differently shaped and sized hands, if we make our wrist pad have a fixed height, it might not be comfortable for everyone, which defeats the purpose of the wrist pad.

This means we may want our wrist support to have an adjustable height and slope.

Since we want everyone to be able to have comfortable wrists, we also want to make sure this wrist pad is easy to make and has a reasonable material cost.

With all these keyboard and wrist issues in mind, let's start designing and implementing our mobile wrist-pad!

• 8 Self Adhesive Caster Wheels/ Mini Swivel Wheels
• 4"x4" Wood Cutouts for Crafts, Rounded Squares
• Foam (various kinds!) and foam sheets
• Double sided tape
• Wood glue
• screws & nuts
• Optional for surface covering: waterproof silicone glue, wooden/soft silicone beads, elastic fabric
• Optional for height adjustment feature: springs, screw sets, drill

We played around with a couple different materials and shapes before we landed on craft wood squares. 

Attach four caster wheels to the square as shown. You can either use the adhesive sticker that comes with the caster wheel or, if you want some extra sturdiness, screw them on using the provided holes. Remember to make one for each hand. Mark them “L” and “R” - the left and right hand wrist rests will be different.

For us, the height of the wood square on the wheels was good already, so we didn't need to add an adjustable height/slope. However, being able to adjust the height and slope of the wrist rest can be useful in some situations. If you don't need this feature, you can skip this step.

Align two wood squares and secure temporarily with tape. Drill 4 holes in each corner (make sure you drill through through both squares!).

Separate the squares and push a screw through each hole of one square. Add a spring to each screw. The spring should be taller than the comfortable height needed for your keyboard.

Add the second board on top of the 4 screws going through the first board. Screw nuts onto the screws and tighten to adjust the height of the wrist rest.

In our first prototype, we carved a spongey foam block to fit the shape of our wrists.

First, cut out the sponge to the size of of the wood square. Lay your right wrist comfortably on the foam (see images for a recommendation of your hand position, but choose a hand position that would be comfortable for you) and trace around your hand with a marker as shown. Begin by cutting out the marked section, then gradually adjust the shape as needed.

Start with your left hand, as it will be easier.

For your right hand, make sure that the wrist rest is comfortable both for keyboard use and mouse use. My mom and I both use vertical mice, so my hand is rotated a different way when I'm using my mouse than when I'm typing on my keyboard. Even for a regular mouse, your hand height and arch will be different than your keyboard hand position. The key is that the forked shape of this wrist rest will help your hand and wrist rest well no matter if you're on mouse or keyboard (see images).

Do not glue the sponge to the wrist rest yet. Skip to step 5.

With a 3D model, we may be able to make a more accurate hand shape using foam sheets.

In Tinkercad, we first create a 4”x4”x1” rectangular prism (width = 4, length = 4, height = 1), then group it with a hand model set to "hole." The hand model we used can be found here: https://www.thingiverse.com/thing:1288. This 3D model is nice because it includes the wrist.

We don't know how to 3D print flexible filaments, which would have made the process a lot easier. Instead, we will try to simulate the 3D printing.

Using Tinkercad, Ultimaker Cura or some other software, take cross sections at different heights. Here we took one cross section each at 0% (bottom), 25%, 50%, 75%, and 100% height (top).

Trace the cross-section views onto 4"x4" paper squares, then use the paper squares as templates to cut out the shapes from foam sheets. Use any color scheme you like. Glue the foam in layers and secure onto the wooden square.

Repeat for the other hand.

Skip step 5. You now have an ergonomic, mobile wrist rest!

The sponge currently has a bumpy surface that doesn't feel great and can get damaged easily. We need to use a piece of elastic fabric to cover them, as in a regular wrist rest. I used an old hoodie because of its elasticity and softness.

Cut your fabric into squares slightly bigger than 4"x4". Using the sponge as a reference, sew each of the four corners of the fabric so that they can wrap around the sponge. Make sure the fabric is inside out. Do not sew the sponge to the fabric yet. Flip the fabric inside out again and place it over the top of the sponge. Sew the top and sides to enclose the sponge. Glue the covered sponge to the wooden square with double sided tape or wood glue.

Now, you can customize the top of your wrist rest to your liking. My mom wanted to try securing a mat made of wooden beads on top of the wrist rest. She says it feels like a massage while she's working! The wooden beads are surprisingly soft - they don't dig into your palms at all.

Thank you for reading my Instructable! Suggestions and comments are greatly appreciated!