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.
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.
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.
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.
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For application assistance contact maxon motor Australia on +61 2 9457 7477.
Welcome to a new year full of exciting technological innovation. maxon motor will again lead the technology push for the most efficient, powerful and dynamic DC motors, gearboxes and controllers.
maxon motor continued to grow in 2016 achieving new records, the maxon motor factory is better, faster and more organised than ever before and all production sites are being expanded. A renewed global focus and streamlining will increase our organisations efficiency with more access to experts in specific application areas. With our increase in capacity and knowledge we will produce more and more complete systems and highly complex sub-assemblies offering further benefits to our customers.
We are eagerly awaiting the Hannover Messe in Germany where maxon motor will present over 18 new products in the 2017/18 program as well as new products launched on the maxon online configuration platform.
I wish all our Australian and New Zealand customers a prosperous year and look forward to helping you succeed.
Managing Director, maxon motor Australia
Tel. +61 2 9457 7477
The number of worldwide medical patents filed in 2015 was more than twelve-thousand. The term “innovation” certainly applies to this industry.
In the field of medical technology, surgeon’s tools and machines are becoming smaller. Robotic assistance is commonplace in prostate surgeries. Minimally invasive surgery, surgical tools that can reach sensitive and in-depth parts of the brain once considered too high-risk, are being explored. Machines that aid faster patient recovery times and robots that assist in rehabilitation. Maxon motors are at the forefront of medical technology, working along-side Universities, start-ups and multi-national corporations. Medical applications that have maxon DC motor technology and expertise include the da Vinci Robot, wheelchairs that can climb stairs, aortic pumps for heart patients, implantable dosage systems, robotic exoskeletons, surgical tools and prosthetics.
For more information on DC motors in medical applications speak to a Sales Engineer from our Sydney office Tel. +61 2 9457 7477 or visit http://medical.maxonmotor.com.au for more medical application examples.
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maxon DC motors can be found in robotic aids, in some cases assisting incomplete paraplegic people to walk again.
Swiss company, Hocoma, is making huge in-roads using robotic equipment to assist in the rehabilitation of people with neurological movement disorders, stroke and incomplete paraplegic patients. There are four different types of equipment that assist with muscular strengthening exercises, exercising joints, sense of balance and improving circulation. In some cases, the equipment has assisted some people to start walking unaided again.
Brushed and brushless maxon DC motors and controllers can be found in all four of Hocoma’s robotic devices. The brushed maxon RE-40 DC motor was selected for its powerful density, ease of control, efficiency level of more than 90% and robust design. The motors ironless rotor delivers low inertia packed with a powerful punch. Also utilised are the maxon brushless EC-60 flat / pancake motors, chosen for their small and compact size and ability to deliver high speeds.
For more information please contact maxon motor Australia on Tel +61 2 9457 7477.
Pictured: the maxon RE-40 brushed DC motor; the maxon EC-60 pancake motor and the maxon ESCON 70/10 controller.
A unique DC motor and gearhead combination developed for an Australian customer providing solutions for robotic rehabilitation.
When high power levels and tight space constraints are required, maxon motor tailor a solution. maxon motor Australia recently developed this motor and dual gearhead design for a robotic exoskeleton application for rehabilitation of children with disabilities. Gearing with the high efficiency level of over 98% on the right angle transfer has been achieved with the use of an sealed, oil filled helical bevel design. A custom adaptor section has then been specifically manufactured to affix a 52mm 113:1 ceramic planetary gearhead at the helical gearbox input. The use of ceramic components within the planetary gearhead increases the lifespan typically by three times compared to traditional steel planetary gearboxes. The 50mm diameter 48V 200W DC maxon motor also achieves the high efficiency of 94%. maxon motor are renowned for high efficiency DC motors but the careful design and selection of the drivetrain components in this gear motor system has set new benchmarks. A common 500cpt incremental encoder has been fitted to the motor back shaft and when combined with the gear ratio and maxon motor control software quad counting, gives a system positioning capability of 0.001 degree. Such a fine positioning capability is also only possible with the assistance of the patented maxon motor rhombic coreless winding that gives a completely smooth motion void of any mechanical detent or magnetic cogging.
For assistance with the design and supply of customised DC gear motor combinations contact maxon motor Australia Ph: +61 2 9457 7477.