Introduction: Paint a Little Picture for Me: a Mouth-Based Assistive Painting Device

Problem Statement:

Due to their limited mobility, individuals with spinal cord injury have difficulty holding a paintbrush and painting using traditional methods. This project aims to engineer a mouth-based device that can be used by individuals with limited mobility in their arms and legs.

Target Audience:

This project targets individuals with spinal cord injuries who wish to create art as a way to pass time and relax but are not able to do so with conventional paintbrushes.

Selected Approach:

This device is an over the mouth styled brush mount. A velcro strap that is worn under the ears that connects a 3D printed mount that holds the paintbrush horizontally (parallel to the ground). This design aims to relieve some of the weight off of the artist, allowing them increased precision and time creating art before feeling fatigued. The device rests on the side of the user’s face while the end of the paintbrush rests in the user’s mouth, which allows for pivoting the brush with ease.


Materials for Device

  • PLA 3D Filament
    • Quantity: 14.2 grams
    • Cost: $21.95
  • Velcro band
    • Quantity: Two
    • Cost: ~$7.00
  • Insulating foam material
    • Quantity: 1.5 in by 1.5 in
    • Cost:~$5.00
  • Masking Tape
    • Quantity: 2 inches
    • Cost: $3.99
  • Paintbrush
    • Quantity: One
    • Cost: ~$1.00


  • 3D printer Solidworks
  • CAD software
  • ImageJ image analyzing software
  • Protractor

Step 1: Competitor Analysis Device 1


This device is estimated to be around $50, but the exact price is not known.


This device is accessible for almost anyone with a spinal cord injury, and can be a fun way for users to move around while creating art. The art is bright and colorful, it is low cost, and few materials are needed.


While using this device, the user cannot see the art being created while creating it. In addition, they have less control over the brush while using it. It is also very messy and requires huge amounts of clean up and space.

Step 2: Competitor Analysis Device 2

Cost: Very few materials are needed for this device, so the cost is approximated to be $10.

Pros: The materials needed for this are easily accessible, and the device can be easily reproduced if given instructions. In addition, it is comfortable and not invasive.

Cons: This device may be difficult for some users if they don’t have enough control over their hand for fine painting skills. In addition, their hand may get tired easily if a large paintbrush is attached, and the device is difficult to clean.

Step 3: Competitor Analysis- Egg Handled Paintbrush

Cost: This device costs $10-15.

Pros: It can be found and ordered easily online. The paintbrush is relatively low cost and can be reused. It is easy to use and clean, and it can be used like a regular paintbrush and offers more control over the art being created.

Cons: The paintbrush may not be appropriate for everyone depending on the severity of injury and the handle may make it uncomfortable.

Step 4: Requirements and Prototypes

The requirements for the device were organized into three levels: 1,2, and 3. Level 1 requirements were absolutely essential, while level 3 requirements were simply ones that would be nice to have. Each prototype was then ranked on a pass/fail system for each requirement. The current prototype for the device is mount 6 foam 3, which is shown in a different color on the requirements matrix.

Step 5: Build

  1. The prototype was designed using Solidworks CAD software
  2. The prototype was printed using a 3D printer
  3. The length of one velcro band was insufficient, so two velcro bands were stapled together to create a longer velcro band.
  4. The longer velcro band was attached to the prototype by looping it through the end without the stub and attaching the hook to the end with the stub.
  5. The insulating material was rolled into a cylinder and masking tape was placed around the foam to create the compression cylinder.
  6. The compression cylinder was pushed into the hole in the prototype to allow the paintbrush to stay there and the paintbrush was inserted into the compression cylinder.

Step 6: User Instructions

  1. Situate the mount over the user’s mouth and loop the velcro band around their head, fastening it to the hook on the opposite side of the user’s face as in the picture above.
  2. Push the paintbrush through the foam with the handle in the user’s mouth.
  3. Approximately 1.5 cm of the paintbrush should be in the user’s mouth.
  4. Position a paper attached to a steady vertical surface
  5. The user should gently use their tongue and teeth to angle the paintbrush and move it over the paper, creating art

Step 7: Safety

  1. Users with long hair should be careful to ensure it is not caught in the velcro
  2. The user should be cautious and ensure that the handle of the paintbrush is not too far inside their mouth.
  3. Users should ensure that a reasonable amount of paint is on the paintbrush so paint does not drip off the paintbrush

Step 8: Care/Maintenance

  1. The compression cylinder and velcro band should be removed before the device is cleaned.
  2. The device can be cleaned by using a sponge and soap and then rinsing
  3. If desired, the velcro strap may be cleaned using a lint roller or a toothbrush by gently running it over the velcro area to remove any built up fuzz.
  4. The paintbrush can be removed from the device and cleaned by slowly swirling it in warm water to remove remaining paint

Step 9: Improvements and Future Extensions

  • In the future, additional foams and mounts could be tested for precision and ease of use
  • An electronic component to the mouth may be added with gears that can move the paintbrush with more control allowing for different angles
  • A better system for mixing paint may be implemented
  • A device that can deal with additional mediums such as clay may be created in the future

Step 10: Works Cited

Artists' Equipment. (n.d.). Retrieved from Blick. "Blick Egg Handled Brushes." blick, blick-egg-handled-brushes/. Accessed 1 Mar. 2020.

NSCISC - National Spinal Cord Injury Statistical Center. (n.d.). Retrieved from Harris, Greg. "Gloves for holding paintbrush." Pinterest, 130956301635375877/. Accessed 1 Mar. 2020.

Staff, W. D. D. (2010, March 16). The Amazing Art of Disabled Artists. Retrieved from Tiffiny.

"Wheelchair Art: Turning your Wheels into a Paintbrush.", 23 Dec. 2013, Accessed 1 Mar. 2020.

Tongue-Operated Devices Help Paralyzed People. (26AD, May 2010). Retrieved from Understanding Spinal Cord Injury. (n.d.). Retrieved from

Young, W. (n.d.). Spinal Cord Injury Levels & Classification. Retrieved from