Progress and Results

The axo-aider has developed the second prototype of assistive exoskeleton to provide sit-to-stand and load carrying/lifting assistances. The exoskeleton was built with the state-of-the-art actuating and sensing technologies and work intelligently and safely. Weighted only 5 kg and assist with maximum 50 Nm at arm, the exoskeleton can be used easily and comfortable at home for the elderly and at workplaces for workers. The exoskeleton is currently being tested at labs. Field tests are being planned in next phase. 

All comments and feedback are welcome. Feel free to contact us for trial and collaborations. 

Contact: Shaoping Bai, shb@mp.aau.dk

Aalborg University had a display area at the annual local LAN-party "Geeks Gone Wild". AAU wanted to give attendees and visitors the opportunity to hear about the educations available at AAU and what these educations can be used for. With 1500 attendees to the event itself and free entry for visitors, GGW seemed like an excellent place to share and spread knowledge of exoskeleton technology. People visiting the AAU stands had the possibility to feel the assistance of passive exoskeleton technology, and to control the Exo-Aider developed E-joint in a fixed test rig. 

We had the opportunity to  attend to the annual Science Meeting (Videnskabsmøde) here in Aalborg where we presented some of the technology developed from the Exo-Aider project. People attending the fair had the opportunity to hear about exoskeleton technology, try to control our active E-joint, feel the assistance from a passive exoskeleton lift their arms, and wear our new Hybrid System that combines both active and passive exoskeleton technology. It was two greatly informative days for both us and the people attending the fair. 

Innovation and exploring new areas of exoskeleton technology to help elderly is a continuous process. We have recently finished developing our first hybrid exoskeleton setup, that combines existing passive exoskeleton technology with the E-Joint. The hybrid system reduces internal forces in the shoulder and makes the already low weight E-joint feel even lighter.

Obtaining feedback from our partners is important to steer the project in the right direction. We had the pleasure of demonstrating the technology of Exo-Aider at Vesthimmerlands Kommune. Here participants had the opportunity to wear the exoskeleton and perform a sit-to-stand motion with assistance. We would like to thank the participants for their feedback on how we could improve the control schemes and ergonomics of the system. 

The demonstration brought joy to both the participants and us as we got to test the robustness of our system, while enjoying the smiles on the faces of the participants, as they experienced the sensation of actively assisted exoskeleton.

:Courtesy of Vesthimmerlands Kommune 

The Exo-Aider project uses sEMG technology to detect the intention of the movement of the user. 

Machine learning based on SVM is used to train the system. One particulartiy is that the training has been performed with one subject and the testing has been performed with another one, which has lead to satisfying accuracy results. 

The exoskeleton system has been tested with Christian, Shaoping, Raza, and Dinh-Son at Wolturnus. 

In an AGILE workflow, customers' specification are a priority to quickly adapt the direction of the project. 

The cuffs are the mechanical part that are directly in contact with the user. They are thus of utmost importance in the overall system. The materials can be based on 3D printing technology for rapid prototyping, but the project aims at using carbon fiber based or kevlar solution (as shown in the picture below). The use of laminate material allows to modify the stiffness of the cuff in the longitudinal and transversal direction to meet a compromise between the torque transfer from the exoskeleton to the user and compliance of the system. 

The mold (left) and the cuff in kevlar (right)

One of the challenge of active exoskeleton technology is to control the actuator depending on the user's intention. The use of surface electromyograph, or sEMG, signal allows to infer the user's intention during a sit-to-stand motion. 

The exoskeleton and the sEMG armband has shown positive results in the detection and the assistance of the motion. 

The initial testing of the joint unit of the elbow joint developed in the project Exo-Aider shows promising results. 

Indeed, the total mass of the joint unit is 600gr. However, it can develop up to 50Nm, which corresponds to carry a mass of approximately 10kg in the hand. 

One of the challenges of the Exo-Aider project is the implementation of a powerful actuator in an upper-limb exoskeleton. Indeed, the weight of the lower-limb exoskeletons are supported by the ground and not by the user, however portable upper-limb exoskeletons are usually worn by a user, which has to bear its weight. The actuator must remain lightweight, while provinding high output torque capabilities since the project deals with bodyweight lifting for wheelchair users. 

One target of the project is the development of compact actuators that would fit the requirement of the task. After rearranging the structure of the custom-made actuator, the version 2.1 of the joint unit is more compact, more lightweight than its previous 1.0 version, with the same power output. 

Joint unit 1.0 (left - 1kg) and 2.1 (right - 0.6kg)

Exo-Aider, with the department of biomechanics, has participated to the Health and Rehabilitation Scandinavia. 

Sharing ideas with experts in the healthcare domain benefits the growth in this research area. 

From left to right, Michael Skipper Andersen, John Rasmussen, Dinh-Son Vu, and Shaoping Bai. 

The first prototype of the Exo-aider project consists of an Elbow joint to assist the triceps extension during the sit-to-stand motion. Further works would include the reduction in size of the actuator. 

Participants from partners and Innovation Fund Denmark's investment manager came to the meeting. The project strategy and work plan, and objectives were discussed. AAU demoed the upper-body exoskeletons developed in previous national and EU projects.

The kickoff meeting took place in AAU-MK with the entire consortium, namely:

• AAU-MK: Aalborg University, Materials and Production
• AAU-ES: Aalborg University, Electronic Systems
• Innovationsfund
• Wolturnus
• Autonomous Fundation
• Vesthimmerland Kommune
• Ningbo University