A light-weight exoskeleton for the elderly.

Graduate students at the National Taiwan Normal University (NTNU) have developed an improved exoskeleton design using maxon brushless DC motors and motor controllers.

Members of the Mechatronic Engineering department of NTNU have developed a lightweight lower extremity exoskeletal robot to assist people who have difficulty walking. The exoskeleton provides support for the hips and knees.

Exoskeletons have been in development since the mid-seventies and have continued to evolve following advancements with technology. Price, weight, safety, ease-of-use, and a proper fit all pose challenges to developing exoskeletons that are practical for the general public.

Graduate students in the Intelligent Automation/Robotic Lab at NTNU found that—due to heavy motors and batteries—most exoskeletons are difficult for users to put on without assistance. The lack of a user-friendly design means that most exoskeletons are inconvenient and can pose a safety risk to the user. Due to the high cost of hardware, they’re also expensive.

Using maxon DC brushless motors and motor controllers for the hip and knee joints, the students were able to develop a high-torque wearable unit that is smaller and lighter. By incorporating lightweight 3D printed components along with high-efficiency DC motors from maxon, the exoskeleton provides an agile, user-friendly solution to an aging population.

The team’s next goal is to extend the development an exoskeleton for the ankle joints and feet, exploiting the same easy-to-wear design as their exoskeleton for the hips and knees.

maxon motor Australia tel. +61 2 9457 7477.

A next step in wearable robotics.

South Korean start-up company, Angel Robotics, focuses on wearable robots for rehabilitation, including robotic suits that allow people with complete paralysis of the lower extremities to walk.

At the global Cybathlon event in November 2020, the team from South Korea won both gold and bronze medals in the powered exoskeleton race. Contestants Byeonguk Kim and Juhyeon Lee crossed the finish line in 3 minutes 47 seconds and 5 minutes 51 seconds respectively and became the heroes of the event.

Notably, they were both from the Angel Robotics team. Angel Robotics had provided the two medallists with both material and moral support in keeping with the slogan “Robotics for better life”. Founded in 2017, Angel Robotics was started by Professor Kyoungchul Kong from the Mechanical Engineering department at the Korea Advanced Institute of Science and Technology (KAIST). The company focuses on wearable robots for rehabilitation and health care.

At the first Cybathlon, Angel Robotics also won the bronze medal in an exoskeleton race using a maxon motor. The WalkON Suit used in the competition is a robot for people with complete paralysis of the lower extremities. For the second event, Angel Robotics’ main focus was on considerably reducing the weight perceived by the user to allow them to stand for extended periods while wearing the robot. The company also made sure that it was possible to cover a distance of at least 40 meters when continuously walking for 1 minute, and improved the suit to match the normal able-bodied walking speed of about 2 – 4 km/h. To date this is the fastest speed reported worldwide for people paralysed from the waist down. The maxon EC 22 DC motor and the ESCON Module 50/8 DC motor controller are used in the linear actuator of the robot’s ankle and help to instigate a smooth and natural movement for walking and overcoming obstacles.

The company has also developed other robots like the Angel Suit robotic walking aid designed to assist people with partial paralysis or the elderly with weak muscular strength. There also is Angel Legs M, a robotic medical rehabilitation device used in hospitals for rehabilitation treatment and training.

Angel Legs M is a robot for people with partial paralysis of the lower extremities who have problems walking. Sensors in the robot analyse the user’s movement and, when the need for support is detected, the robot provides appropriate strength. When the user lifts their leg, the weight of the leg is reduced, and when the foot touches the ground, supporting force is provided. The maxon EC 45 flat DC motor, MILE encoder, and the ESCON Module 50/8 controller implement the robot’s hip joint and knee joint movement and are used to provide smooth and meticulous supporting strength.

Angel Robotic’s senior researcher Byunghun Na (R&D team) had the following to say about maxon: “When it comes to wearable robots, the weight and size of the motor are very important considerations. The output is important, too, but in order to minimise the load on a user who may have limited strength and to make it easier to get in and out of the suit and to create an acceptable robot design, the motor drive has to be as light and small as possible. Among brushless DC motors for various purposes, maxon motors are light and small for their output and highly efficient. They are suitable for robots that are sensitive to size and weight. maxon has different kinds of DC motor groups and it is easy to choose a DC motor for the desired output. Since the stability and inner structure are excellent, we are able to increase user confidence in rehabilitation robots.

Given social factors like the increasing ageing population, wearable robots are set to become an essential robot technology for all of mankind, not only for the disabled. To achieve this, maxon is taking the lead in continuous product development and technological enhancement in service of a better life for everyone.

maxon motor Australia tel. +61 2 9457 7477.

maxon motor Australia – COVID-19

Medical Industry prioritisation and emergency sector fast turnaround markets.

During the extraordinary and challenging times the COVID-19 virus has brought about, maxon motor Australia would like to extend our wishes of good health to all customers, staff and suppliers.

In response to the corona virus outbreak maxon group have established a task force to help address the many challenges including staff isolation, continuance of supply, logistics and most importantly the service and delivery to our important medical industry customers.

maxon group supply high end medical products across a broad range of hospital applications, and most importantly at this time, life-saving medical ventilators. As such maxon have established a fast track for medical and associated critically important applications. We would like to ask any customers in this category that we have not already been in contact with and are experiencing hyperactivity on demand or forecasts, to please register this with our staff. maxon would like to prioritise raw material and production capabilities around medical applications first. Our supply chain and production sites are flexible, adaptable and reliable.

For more information or to get in touch contact maxon motor Australia tel. +61 2 9457 7477.

© 2020 by maxon motor Australia

A mechatronic orthosis glove, for restoring mobility to the hand after an accident or stroke.

A specially developed glove with maxon DC motors provides strength and mobility to the wearer.

Two medical engineers have created a glove that restores mobility to the wearer’s fingers. The mechatronic orthosis, called the exomotion® hand one, is in its testing phase and available soon to the market. The exomotion® hand one is worn like a glove and consists of custom-fitted exo-finger mechanics, a supporting forearm splint, a sensor, a control unit, and four miniature drives that provide the power to open or close the wearer’s fingers. Six types of grip are available, restoring freedom of movement that may have  been lost as a result of accident, stroke or degenerative disease.

The hand orthosis was developed by Dominik Hepp and Tobias Knobloch, both medical engineers. They first met in university, where they both focused on this issue and founded start-up company HKK Bionics, in 2017. The two men hope to close a gap with their development: “We offer patients with fully or partially paralysed hands an aid than helps them to perform everyday tasks on their own again,” explains Dominik Hepp. Simple tasks like cooking, carrying shopping bags and opening packages will soon become part of the wearer’s daily routine again. “With an aid that is suitable for everyday use, these people can regain a degree of independence in their daily lives.”

The development of engineering medical prototypes is not without its challenges. The orthosis is intended to be worn all day long therefore it needed to be robust, high-performing and lightweight. After developing the initial prototype, the main focus was on making everything smaller, including finding suitable new components. “That was a real challenge, since we couldn’t accept any compromise in terms of stability or performance,” says Dominik Hepp. To solve this problem, the two designers collaborated with suppliers to develop special components. At the core of the hand orthosis are four customised EC motors from maxon. These requirement was not only small in size and powerful, also the DC motors had to guarantee years of service with hundreds of thousands of operating cycles. The brushless micromotors deliver the necessary grip strength and are controlled via sensors that respond to still-intact muscles, a principle that is also found in prosthetic arms.

2019 is a year of practical trials for HKK Bionics, as the product goes through extensive testing before it is approved and becomes available on the market. “We want to make the exomotion® hand one accessible to as many patients as possible. That’s why we are pursuing collaborative partnerships with selected medical supply stores while expanding our network to include doctors and therapists,” explains Dominik Hepp. For the two young businessmen, this is an exciting challenge at the interface between technology and human beings. “It’s great to see that with our experience, plenty of creativity, and some tinkering around, we can contribute to improving the quality of patients’ lives.”

For further information please contact maxon motor Australia tel. +61 2 9457 7477.

maxon motor new Innovation centre is now open

In November 2018 after 2 years of construction, a new centre for the manufacture of microdrives in the medical technology industry officially opened in Sachseln, Switzerland.

To keep up with demand maxon motor built a new Innovation centre for continued collaboration of various R&D departments as well as state-of-the-art cleanrooms to produce microdrives for use in the medical technology industry. These DC motor drives are used in insulin pumps, medication delivery systems or surgical robots and the cleanrooms enable maxons’ continued fulfilment of highest quality standards.

The new building is the fifth building at maxon headquarters. A solar panel system on the rooftop provides up to 180 megawatt-hours of energy every year. More than 1200 employees currently work at maxon headquarters. The Innovation centre cost approximately CHF 30m and represents an important part of maxon’s growth strategy. “With this step, we are strengthening our Swiss headquarters and our ability to focus even more on individual markets worldwide,” says maxon CEO Eugen Elmiger. The measures include establishing a global R&D team and continuous expansion of the eight production sites. With more than 2600 employees worldwide, the company is set to focus on complete drive systems and their integration into a wide variety of applications.

For more information on drive system solutions particularly in the medical field please contact maxon motor Australia tel. +61 2 9457 7477.

Design considerations for an exoskeleton for children

Developing Exoskeletons for children present their own engineering challenges simply because children are still growing.

Exoskeletons were largely developed for people that have sustained paralysis or suffer muscular dystrophy. For adults who have stopped growing there is no risk of outgrowing the exoskeleton. However for children their growth and ability present a multitude of challenges for design engineers. An exoskeleton that fits a six-year old perfectly may be much too small by the time the child turns seven. For a child with spinal muscular atrophy an exoskeleton is designed to recognise users are not completely paralysed but are able to move their legs to a certain extent. Sensors within the frame detect weak leg movements and respond immediately to provide support. As a result, the child is able control the exoskeleton directly with the legs.

Spanish company, Marsi Bionics, manufactures exoskeletons mainly for adults but have developed two exoskeletons for children, the Atlas 2020 and Atlas 2030. Weighing approximately 14 kgs it is made for children from 3 years up who have a neuromuscular disease. The exoskeleton can be adapted to various leg lengths and hip widths, so that it also fits teenagers up to about 14 years of age. The “Atlas 2030 is an upgrade of Atlas 2020”, explains Elena García, creator and co-founder of Marsi Bionics. “The main difference is that Atlas 2020 is intended for use in hospitals for gait training and rehabilitation, while Atlas 2030 is designed for use in private homes as an integral part of the patient’s everyday life. Both devices are ready for industrial production and until then, Atlas 2020 will continue to be used in hospitals for clinical research.”

maxon motor have five drive systems in each leg of the children’s exoskeleton. Brushless flat EC45 motors deliver very high torque in a compact design, coupled with inductive MILE encoders that act as sensors. The motors are controlled by servo controllers from maxon’s ESCON series.  “EC flat motors provide the best power-to-weight and power-to-volume ratio”, explained Elena García. “This is a variable of paramount importance, as gait exoskeletons require high power but a very low weight and volume.” The exoskeletons will be made available commercially once CE certification marks have been received.

For more information contact maxon motor Australia Tel. +61 2 9457 7477.

Inspired by nature. Created by engineering. Powered by maxon.

Biology and engineering have been combined to create the world’s first prosthetic foot with propulsion powered from a maxon DC motor.

Our calf muscles provide the essential power, control and stability for walking. Those who’ve had below the knee amputation tire very quickly walking on a prosthetic foot. Step in Hugh Herr, Professor at MIT Boston who developed The Empower bionic prosthetic foot along with the Ottobock Group, a world-leading supplier of prostheses. Hugh himself is a double transtibial amputee resulting from a mountaineering accident. Hugh and his team drew inspiration from nature to create The Empower combining both biology and engineering together.

The Empower is a third generation newly developed bionic foot. A research team spent 16 months to make walking feel more natural by using a carbon spring which transfers energy directly to the foot. A powerful maxon DC motor refines the energy pulse delivered by the spring and provides the missing power of a calf muscle, step by step with each toe push-off. Several sensors “tell” the prostheses which phase of movement the foot is in, at any given time, so that it can perform the corresponding action. This allows for short sprints, which were previously deemed impossible, as well as walking on uneven ground and up inclines. What’s more, the greater the load on the prostheses, the greater its energy output becomes, just like a natural foot. The DC motor providing the propulsion is maxon’s EC-4pole 30. Selected for its powerhouse features and high output per unit of volume and weight it provides an ideal ratio between size, weight and power – a key factor in developing prosthetics.

For more information on prostheses and robot assisted rehabilitation please contact maxon motor Australia tel.+ 61 2 9457 7477.

A new prosthetic bionic hand

Prosthetics are a significant engineering challenge because of their conflicting DC motor design goals: high torque, high speed, compact size and the DC motors need to be as energy efficient as possible.

German company Vincent Systems have created a bionic hand prosthesis that is the first commercially available prosthetic delivering haptic feedback about grip strength to its wearer. This is achieved with short pulses of vibration. If the hand were to vibrate evenly, a person becomes familiar to the sensation and eventually stops paying attention to it.

What sets this prostheses apart is that each finger can individually open up. This opens up numerous situations for the wearer such as being able to ride a bike, tie shoelaces, hold a raw egg or open a door. 12 grip patterns are available that can be activated via muscle contractions. Weighing about the same as a human hand it’s available in a version small enough for children, with the youngest wearer being eight years old.

Each individual finger is actively driven by a DC motor, and the thumb is driven by two DC motors. Maxon have up to six brushed DC motors in the hand: DCX 10 DC motors with modified GP 10A planetary gearheads. The drive systems were selected for their compact size and highest energy density currently available from maxon. Plus the drives needed to be durable and function faultlessly for approximately five years while being exposed to diverse and heavy strain every day.

It was important to CEO and founder of Vincent Systems, Stefan Schulz, that patients wouldn’t need their healthy hand to help. “A prosthetic hand should help its wearer and not demand the attention of the good hand.”

For further information please contact maxon motor Australia Tel. +61 2 9457 7477.

 

Multi-axis control of DC motors.

Getting the balance right with mechatronic systems involves the focus on a whole system and using modular motor system components for successful integration.

The new educational website by maxon motor drive.tech showcases the latest technologies and applications in the advanced motion control world. Dr Urs Kafader’s new article explains the process of getting the balance right in the critical motion control application of modern prosthetics.

Artificial limbs have rapidly moved into the world of advanced mechatronics. The synchronisation of multiple DC motors, sensors, transmissions and processors has become decentralised. The DC motors in these systems are required to fulfil an increasing number of functions that could soon encompass every human (or animal) movement. As such a huge variety of dynamics within the DC motor are required and modularity of components becomes a powerful ally. Each motor in these dynamic multi axis coordinated systems can now be locally controlled with real time field buss communication with full interpolation.

Visit drive.tech for full application white papers or contact maxon motor Australia on +61 2 9457 7477.

Out now! driven app from maxon motor.

Download the App ‘driven’ for access to all maxon motor magazines.

A refreshed and updated version of maxon’s App driven is out now!  Available in the Apple and Google Play stores (and soon to be available on the Windows Store). driven app contains technical information on DC motor systems, up-to-date & hot off the press stories from industries including Industrial automation & Robotics, Medical and Aerospace applications. Improve your know-how in DC motor and drive technology.

Available in English and German. Find us by entering “driven” and “maxon” in the search field.

For application assistance contact maxon motor Australia on +61 2 9457 7477.