How Does it Work?
Unlocking and Positioning
Free-swing
Changing Components
The Hexa-Flex Arm is designed for straightforward mechanical operation and adjustment.
The Hexa-Flex joint is operated manually using an opposing hand or an attached terminal interface. To reposition the joint, the handle is grasped and the pull-and-twist actuated control knob is drawn away from the socket, disengaging the locking mechanism between the handle, forearm section, and the hexagonal ball interface. This allows the forearm section to be rotated around the ball’s axis. Once the desired orientation is selected, releasing the control knob re-engages the locking mechanism to secure the joint.
The control knob may also be fully pulled and rotated into a disengaged position, allowing the handle and forearm section to move freely around the hexagonal ball interface. This free-swing configuration permits unrestricted mechanical movement when desired.
When a different mechanical configuration is needed, forearm sections and components may be exchanged using a quick-release button integrated into the handle body, allowing forearm assemblies and attached components to be removed or installed without tools. The modular architecture supports multiple build configurations, including varied forearm lengths, interchangeable terminal connectors, extension sections, wrist adapters, and dual-joint arrangements, depending on system layout requirements.
The Hexa-Flex Arm may also be configured to mechanically interface with harness-based actuation systems for operating compatible normally open or normally closed terminal devices, when installed and adjusted by a qualified professional.
Examples of different mechanical configurations are shown in the Gallery section.
How much Freedom does the Hexa-Flex Joint Provide?
+/- 30° Yaw
360° Roll
130° Pitch
Hello
My name is Jason Morris, and I am the designer of the Hexa-Flex Modular Arm System. In 2012, I lost my arm above the elbow in a traumatic industrial accident, an experience that led me to focus extensively on mechanical arm systems and the individuals who design, build, and use them. The Hexa-Flex Arm was developed in response to the high cost and practical limitations associated with many existing electromechanical arm solutions. My objective was to create a mechanically robust, lightweight, and adaptable modular system that can be configured for a wide range of use scenarios. When integrated with a compatible socket and terminal attachment of your choosing, the system is intended to serve as a reliable, frequently used mechanical arm configuration.
My Story
Like many individuals with limb loss, I was introduced to the field of prosthetic systems while searching for a practical way to replace my missing limb. Over time, I have used a wide range of arm systems, including passive cosmetic arms, conventional body-powered configurations, and advanced electromechanical systems that use sensor-based inputs for movement control. I have also had the opportunity to work with and represent several organizations within the prosthetics and assistive-technology space, and I have consistently enjoyed discussing and demonstrating different mechanical approaches with new users and individuals with congenital limb differences.
One of the arm systems I relied on most was a simple mechanical “rehabilitation” or “stick-style” arm designed to support a variety of work and recreational tasks. This system allowed limited up-and-down movement with a small number of fixed locking positions and could be attached to an existing socket using interchangeable terminal attachments. Its low weight and straightforward mechanical behavior made it easier to configure and use compared to more complex systems, particularly for tasks that required repeatable positioning. While other arm systems could be configured for similar activities, they often required additional adjustment, added mass, or more complex operation.
In practice, I encountered several mechanical limitations with the systems I used. Some configurations restricted positioning options at the elbow or wrist, making certain activities difficult to perform comfortably. Others lacked sufficient structural support for higher loads or repeated use, leading to wear at threaded interfaces or reduced service life. More complex electromechanical systems, while highly capable, were not always practical for environments involving tools, impact risks, or debris, where unintended movement or damage could occur.
After experiencing these limitations firsthand, I set out to design a mechanical joint system that better aligned with my own requirements for strength, weight, adjustability, and reliability. The goal was to develop a modular joint architecture capable of providing a broader range of mechanical positioning with secure locking at selectable angles, while remaining simple to configure and maintain. Through iterative prototyping and testing, this development process led to the creation of the Hexa-Flex Modular Arm system.