The Apex exosuit by HeroWear LLC is made for workers in the logistics industry to fight fatigue in the workplace. Designed without motors or batteries, the science-backed Apex weighs just 3.4 lbs. and can reduce over 50 lbs. of strain on the back. In addition to the core benefits of reducing the strain, the textile-based exosuit is designed to keep workers cool and comfortable. It's backpack-like design is intuitive to put on and take off, is lightweight and has a low profile that avoids interference with the workers movements and allows for a wide range of motion. The modular design accommodates 56 size adjustments, addressing a wide range of body shapes and sizes including the first ever gender specific fit options. The Apex is the first exosuit designed to accommodate women. This inclusive fit system mirrors the diverse warehouse teams across the logistics industry.
There are numerous benefits for companies as well. Back injuries compromise worker health, wages, and productivity — and they happen to be the most common injuries. Overexertion is the leading cause for work-related musculoskeletal disorders (WMSDs) that contribute to claims and escalating medical costs.* In fact, according to one study, back pain costs our healthcare system over $100 billion a year for medical care, workers compensation payments, and time lost from work. The competitive price point for the Apex allows companies to equip more workers with an assistive device.
Operating the Apex is simple for the user. After fitting the device to the worker's shape and strength, the user reaches for the switch placed on the left strap to engage the Apex suit before picking up an object. When taking a break, rather than doffing the entire suit, the user disengages the Apex with a click of the switch. The mechanism for the load absorption is powered by a combination of mechanical hardware and elastic latex bands that act like artificial muscles. The clutch locks a rotating coil and the spring-back mechanism of the latex absorbs the load.
The Apex exosuit supports the hardworking employees of the logistics industry to lift their spirits and protect their bodies while helping companies protect their investment in their most valuable resource - their workforce.
* Deyo, Richard A. "Back Pain Patient Outcomes Assessment Team." Agency for Healthcare Research and Quality, September 1994, https://archive.ahrq.gov/clinic/medtep/backpain.htm. Accessed 29 January 2021.
In 2019, a group from Vanderbilt's Center for Rehabilitation Engineering & Assistive Technology developed a proof-of-concept prototype for a mechanical exoskeleton that could alleviate strain on the lower back for repetitive task workers. They approached Interwoven Design Group to design and develop their technology into a fully commercialized product. the product was launched in March 2020.
Using an evidence-based approach, the Interwoven team took on the challenge by first visiting warehouses to gather demographic information, log worker movements, and conduct interviews to determine the core features needed in the product. The key requirements were determined to be, ease of use, comfort, breathability, lightweight, a low-profile design so as not to interfere with their workflow, and above all else a demonstrated benefit for the worker. Logistics workers are highly monitored and they already wear a number of tools that quantify their work for the company. Interwoven discovered that prioritizing the worker over the company would reduce the barrier to adoption.
Initial research showed that one of the pain points for the logistics industry was missed work due to pain and injury leading to a high turnover rate. The turnover rate in the warehouse industry is ranked as one of the highest across all industries which leads to a cycle of understaffed teams, lost time spent on training new workers and increased costs for the company. The Apex by HeroWear exosuit resulted in a worker-centric design which prioritized the worker's wellbeing while helping businesses lower their turnover rate.
One of the key innovations of the final design is that the functional mechanisms are non-electric. This approach allows for quicker and easier repairs, on-site maintenance, and the replacement of only part of the whole exosuit should it break.
Interwoven created the Apex suit with an easy-to-understand backpack-like design that allows for a personalized fit. A key takeaway from the warehouse visits was early stage worker acceptance would be critical to the product's success. Interwoven would achieve this by focusing on worker comfort and demonstrating that the Apex would benefit worker's overall lifestyle, giving them more energy to enjoy life after work. The Apex Suit's modular design, accommodates 56 body size configurations. It is also the first exosuit to be designed for women. The backpack-like straps are shaped and sized by gender and body size. The women's straps have a curvilinear pattern shape with an open chest design to accommodate women's bust and narrower shoulders. The Apex's design also allows for a greater range of movement and is designed to accommodate women who physiologically have a greater Q-angle as compared to men. (The Q angle, which is also known as quadriceps angle, is defined as the angle formed between the quadriceps muscles and the patellar tendon. Q angle has become accepted as an important factor in assessing knee joint function and determining knee health in individuals suffering from anterior knee pain.)
The functional stress on the users back muscles are off loaded to two latex bands that act as a type of artificial muscle. They are sized by the individual's strength and height. They are attached between the back component and the thigh sleeves. The thigh sleeves are sized by the individual's thigh circumference. With adjustable velcro closures, they can be fit to accommodate many different size legs allowing each worker to find their true fit and to maximize both comfort and function for the Apex during use.
The textile-based garment system allows for a comfortable and breathable exosuit. Typically, the inside of a warehouse is not air-conditioned and summertime heat can be very uncomfortable. Comfort in the form of air flow, moisture management and breathability were major design requirements. Interwoven achieved this with both the physical design as well as fabric selection. Inside the back component, a foam offset pattern was developed to increase airflow on the wearers back by creating small channel-like spaces between the worker'' back and the garment, allowing heat to escape and air to be ventilated for evaporative cooling. Interwoven worked with a PhD student in mechanical engineering at Georgia Tech University to develop the reverse chevron pattern that optimizes and promotes air circulation and air flow across the back of the wearer. Spacer mesh and moisture wicking performance fabrics were used on panels with direct contact to skin for more breathability and ventilation.
One of the biggest challenges Interwoven faced was designing a durable and lightweight clutch mechanism that would engage and disengage the assistive bands. It also needed to be easy to manufacture and repair. The size and placement on the body was critical so that it would not interfere with the worker's on job tasks. The original proof-of-concept model developed in the Vanderbilt lab consisted of two metal clutches located in the lower back. It had cast metal cams with a toothed surface that would bite into webbing activating the elastic stretch. This design was difficult to operate consistently and costly to manufacture. By consolidating the function to a single location on the body and creating a more efficient design, Interwoven cut production cost in half and improved the durability of the clutch.
In the final design, the clutch engages the bands and uses torsion springs to keep slack in the system in check when it is disengaged. This feature avoids interference in the work environment while enabling the worker to climb stairs and sit with ease and comfort. When the clutch is engaged, the torsion springs are locked, and the latex bands assist the worker when lifting. The clutch assembly is applied to the back component with a mounting plate that is enclosed inside a complex multi-layered configuration. Internal support in the back component is achieved with multiple layers of materials. The layers of the back component consist of Volara foam and a soft LDPE interlining beneath multiple fabrics chosen for strength, comfort and durability. The straps are constructed from layers of Volara foam with perforated oblong shapes to allow for additional flexibility and ventilation. A small panel of ?" foam on the shoulder area provides additional comfort when lifting and an LDPE panel is sandwiched between the foam layers to add strength and rigidity for the switch mounting.
On the development of the linear switch, Interwoven worked through 10 different iterations considering functionality and aesthetics. The switch is located in the upper portion of the strap - a position easy to touch but nor easy to see. The user interaction needed to be intuitively to indicate to the user when the exosuit is "on" or "off" position. The IW team developed a click and slide switch mechanism that had a discernible click that the user could both hear and feel.
Another aspect of switch design was its compatibility with the straps and back of the modular garment system. The switch needed to be permanently attached to the clutch but in order to change straps styles and sizes we created a 2 part system consisting of the switch and a hot shoe. The hot shoe component is applied on each strap and the functional component of the switch is wired to the clutch. Once the strap and back are selected and assembled the functional part of the switch slides onto the hot shoe. This helps the user save time when fitting the garment, but also reduces cost by making the functional components of the switch universal.
Finally, Interwoven tested the switch in different materials by 3D printing and milling different plastics to find the best material for performance and the durability of the switches living hinge during repeated depressions.
In testing with the device in use, the Apex has shown "reduced erector spinae muscle activity by an average range of 14 to 43 percent."[1] Translated, this means that the suit reduces more than 50 pounds of strain off the lower back. Additionally, fatigue of lumbar muscles have been found to be reduced by 19-85%[2]. It's lightweight and comfortable design is easy to don and doff and design details improve body heat buildup. An agile device, the Apex doesn't interfere with either worker's tasks or everyday movements. Not only does it improve the wellbeing of logistic workers in repetitive movement tasks but for their employers, the product reduces workers injury and turnover. Its modular design accommodates a wide variety of body shapes and sizes and it is the first of its kind to address the female physical form, making the Apex the first exosuit for all.
1: E. P. Lamers, A. J. Yang and K. E. Zelik, "Feasibility of a Biomechanically-Assistive Garment to Reduce Low Back Loading During Leaning and Lifting," in IEEE Transactions on Biomedical Engineering, vol. 65, no. 8, pp. 1674-1680, Aug. 2018, doi: 10.1109/TBME.2017.2761455.
2: E.P. Lamers , K. L. Scherpereel , J. C. Soltys , A. J. Yang , K. E Zelik, "Effect of Low-Profile, Spring-Powered Exosuit on Back Muscle Fatigue during Leaning" 2019 https://cdn.vanderbilt.edu/vu-my/wp-content/uploads/sites/1409/2016/03/14121714/ISB_2019_EPL_01302019.pdf. Accessed 29 January 2021.