Ergojack is a "wearable soft robotics system". Researchers at the Fraunhofer Institutes for Production Systems and Design Technology IPK and for Reliability and Microintegration IZM in Berlin have developed a soft orthosis that relieves strain on the back and encourages workers to perform strenuous movements ergonomically.

Not a conventional exoskeleton
The unique selling point of the soft robotic upper body orthosis is real-time movement analysis. Specially developed algorithms based on machine learning and AI enable the ergonomics analysis. This distinguishes the orthosis from previous exoskeletons - i.e. support robots that, in principle, simply provide power support for all movements, including non-ergonomic ones, and merely redirect the wearer's stress forces from overloaded to less stressed areas of the body. The movement analysis of the IPK orthosis, on the other hand, recognizes ergonomic and non-ergonomic movements. The wearer receives real-time feedback via a vibration alarm if they adopt postures or perform movements that are harmful to their health.

The Ergojack soft orthosis with lockable hip joint and leg stirrup supports the employee when lifting heavy loads. © Fraunhofer IPK

AI in the vest
Inertial movement sensors (Inertial Measurement Unit IMU) integrated into the vest compare pre-learned movement patterns with the actual movement and evaluate them in real time; this takes just a few hundred milliseconds. The miniaturized movement sensors are located on the shoulders, back and thighs. In addition to these sensors, robust, miniaturized electronics including an embedded controller, a vibration module and a rechargeable battery are integrated into the orthosis. Fraunhofer IZM is responsible for developing the miniaturized electronic components, while Fraunhofer IPK is responsible for designing the system layout, human-system interface, mechanics, electronics and software, including the real-time algorithm with machine learning and artificial intelligence.

Variants and further developments
Data processing runs directly on the vest. The training process only requires a small movement training data set. The Fraunhofer researchers are working on encapsulating the electronics and sensors of the textile version of the orthosis in such a way that they are washable and do not have to be removed from the vest. In future, customers will be able to choose between a purely sensory textile vest and a version with power assistance.

Another current system variant with back and hip support was designed with a minimal orthosis support surface on the body. The power transmission from the back to the legs can be switched on and off using a lockable lateral hip joint on the vest. This mechanism enables alternating activities while standing and sitting. pb