Design considerations for an exoskeleton for children.

Exoskeleton for children maxon DC motors

 

 

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.

Brushless DC flat motors – in parts.

BL Frameless DC motor + encoder 450px

maxon motor Australia’s new frameless DC motor and encoder set allows even further miniaturisation and integration. The new motors meet the increasing need for smaller robotic actuation by assembling individual parts directly into the robotic joint.

This is the new frameless brushless DC motor (BLDC) with a diameter of 45mm and an assembled depth of just 23.7mm, it has a continuous rating of 50W. 70W and 130W versions are also available. The frameless design is particularly suitable for processing machine or rotary stage manufacturers who need a large through bore to pass cabling or tubing. For positioning a high resolution magnetic encoder ring also with the same bore as the motor rotor is also supplied as components. The encoder ring is marked with the zero position to allow alignment with the motor zero commutation point in the application and is available in IP rated, absolute and incremental options. The combination gives a low profile large bore positioning system made up from standard parts with shorter lead times than specialty manufactured complete assemblies. The second advantage is for space saving in applications already containing joint actuation bearings or mounting systems there is no need for a second set within the motor.

Contact maxon motor Australia for assistance with brushless frameless DC motors. Ph: +61 2 9457 7477.

 

Tailor made brushless DC servomotor and planetary gearbox.

Small brushless DC motor and planetary gearbox 450px

This small brushless DC motor displays the advanced miniature and micro motor manufacturing techniques of maxon motor. So small are the details it is hard to capture the modifications and quality. The example pictured is a 10mm diameter DC motor and planetary gearbox fitted with an encoder for speed and position control.

What’s new? Sure there are a lot of small DC motors available now days however it’s in the detail that defines the difference between motors. Pictured is maxon motors newest planetary gearhead range that has been selected because of its stainless steel construction. The body and flange of the gearbox are one piece allowing the design engineers to not only create a mounting flange specific to the mounting footprint available in the application, it also allows maxon motor to orientate the gearhead flange with the motor cable exit. Enabling a shorter cable and neater cable looms. Laser welding of the motor flange is also a technology that is used to affix a customer specific drive pinion to the shaft. This gives the strongest possible power transmission coupling in these miniature sizes. maxon motor provide its customers with complete drawings and models for appraisal before samples are manufactured even for non-standard DC motor and gearhead assemblies like the shown example.

The new 10mm gearhead can supply torque levels up to 200mNm and can operate with input speeds up to 15,000rpm. Standard supply is with stainless steel ball bearings, it has efficiencies as high as 90% and weight as low as 6.7g.

Contact maxon motor Australia for further assistance Ph:+61 2 9457 7477.

 

New powerhouse DC motor positioning controller.

EPOS 70-10 controller

maxon motor have developed their most powerful DC motor positioning controller to date.

With a maximum power output of 2.1kW maxon are pleased to announce the release of the EPOS4 70/15 DC motor positioning controller. The CANopen controller with an EtherCAT option is presented in a robust metal housing. Suitable for both brushless and brushed DC motors the positioning controller is a cut above the rest due to its ease of operation and broad operative scope. The various digital and analogue connections can be configured and the unit is suitable for use with a wide variety of feedback systems. It can also be integrated into various master systems. This new product and many more will be showcased at the Hannover Messe in Germany from 23-27 April. For more information please contact maxon motor Australia tel. +61 2 9457 7477.

DC motor positioning controller with additional benefits.

EPOS4

There are additional connectivity options with maxon’s positioning controller, the EPOS4.

The addition of an expansion board now allows maxon positioning controller, the EPOS4, to be integrated into any EtherCAT network as a slave using the CoE standard (CAN application layer over EtherCAT). The EtherCAT card developed for this use can be combined with the EPOS4 controllers in a housing, as well as with all EPOS4 modules. The benefits widen the applications where compact positioning controllers are needed, for example where short cycle times are important in synchronized multi-axis systems.

EPOS4 controllers are suitable for controlling both brushed and brushless DC motors. They are known for their high power density and excellent value for money. For more information about maxon’s EPOS controllers, please visit epos.maxonmotor.com or tel. +61 2 9457 7477.

Powerful zero backlash servo gear motor.

Powerful zero backlash DC motor

Brushless DC (BLDC) servomotor, zero backlash gearhead, holding brake and high resolution encoder combination drive offers high torque levels without compromising positioning accuracy.

This servo motor and gearhead combination recently released by maxon motor Australia can produce 364Nm with a peak torque rating at the output of 686Nm. Fitted with both an encoder and a holding brake inside the IP rated motor’s rear enclosure the combination can move heavy loads into position and make sure they stay there. The high acceleration of the brushless DC motor with top grade Neodymium magnets enables a zero to 2600rpm speed change in under 4ms. Being both brushless DC and also slotless gives the motor zero cogging or position detent for smooth position transitions and low speed performance. The solid construction and sealed nature of the motor drive components makes it suitable for mining, food, process control and manufacturing environments. Customisation of the motor and gearhead features is possible and both 24 and 48V DC supplies can be used. The unit is compatible with standard Servoamplifier and position controllers from maxon motor.

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

Robots for playing soccer through to disaster relief

Rescue robot

At the international RoboCup, maxon motors featured in robots playing soccer and in mock recovery operations.

At the end of July 2017, more than 3,000 participants from 42 countries participated in the annual RoboCup competition held in Nagoya, Japan.

maxon had inbuilt motors and controllers in a rescue robot developed by the Carinthia University of Applied Sciences that placed seventh out of 20 competitors. Scoring high marks for the light design and system approach, the robot contained several DC motor, gearbox and encoder combinations. Using the EC-4 pole brushless motor with 200W power as a base, the motor operated the chains propelling the robot forward. The camera arm of the robot also contained eight maxon DEC 50/5 modules on circuit boards and four 70/10 ESCON controllers for the gripper arm. The machines acted in a simulated disaster scenario carrying out rescue operations and were evaluated based on their performance.

At the other end of the contest was the Soccer finale, with the two competing robots both containing maxon drives. The University of Bonn developed an 18kg, 135 cm robot supported by an exoskeleton that was 3D printed called “NimbRo”. Maxon DC motors were integrated into an actuator drive system developed by a South Korean company. The competitor’s robot, named “Sweaty” and developed by Offenburg University, contained 24 maxon DC motors and gearheads. 18 of these drives were fitted with an overload motor controller and a further two were fitted with an evaporative cooling system to prevent overheating. This cooling system is similar to the way humans sweat hence the name “Sweaty”. NimbRo won 11-1.

For more information on DC motors to develop robotic applications contact maxon motor Australia tel. +61 2 9457 7477.

 

 

 

Saving the lives of preemie babies.

Paul-2

Paul is a robotically simulated training model of a 27 week old preemie baby. Created by an Austrian paediatrician to help train medical practitioners, maxon motors replicate the breathing movements of the baby.

Meet Paul. The smallest and most advanced high-end patient simulator in the world. Paul is a 27 week old preemie. He is 35cm long and weighs 1kg. He breathes on his own with a consistent heartbeat. His chest gently moves up and down, veins and arteries are visible under his thin skin. Paul needs artificial respiration and will sometimes turn blue.

Born to train medical staff in emergency situations that occur every day in neonatal intensive care units, the creator of Paul is Jens-Christian Schwindt, an ex-paediatrician in the Division of Neonatology of the Vienna General Hospital. In 2015 Schwindt started his company SIMCharacters, that arose from a need where “Critical situations in preterm care have to be trained time and time again, under as realistic conditions as possible, to ensure that everything goes equally smoothly in a real crisis” says Schwindt. With the ability to evoke emotions and cry, the baby looks exceptionally lifelike and is full of high-technology on the inside. His skull hosts a Linux system, he is charged cordlessly by induction using a customary charging pad. Paul can be operated for up to two hours. When he has difficulty breathing or the oxygen saturation drops, his head turns blue. Sophisticated hardware and software fit into a silicone skin.

maxon DC motors, gearheads and sensors ensure that the thorax and abdomen move in accordance with the programmed test scenarios. Three DCX 12mm motors with gearhead and sensors are used – two for Paul’s thorax and one for the abdomen. Another maxon DCX 6mm motor moves a valve in the lung of the simulator, with a total of 40 motors installed. The motors were selected for their torque, density and quiet running. The robust design and the ironless maxon rotor make these motors a perfect fit for this unique application. Maxon’s DCX motors are brushed and available in sizes from Ø 6 – 35 mm. They can be easily configured online and customer can select from graphite and precious metal brushes, sintered and ball bearings, and many other components.

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

New and improved high-resolution encoder from maxon.

ENX_16_RIO_450px

Compact and housed in robust casing is the improved ENX 16 Encoder that withstands temperatures from -40 °C to +100 °C.

For exceptional accuracy and position control, maxon’s ENX 16 encoder offers resolution up to 65,536 CPT. It is small, packed in a diminutive 16mm outer diameter size and only 7mm in overall length. The housing is mechanically robust and protected from dust due to its injection-moulded construction. Ideal for accurate positioning and speed control of DC motors, it fits the new brushless EC-i 30 motors and 16mm + dia. brushed DCX motors. maxon’s ENX 16 encoder has several aspects that can be configured online or at the factory, including the resolution, counts per turn, the electrical interface, as well as combined and configured with matching DC motors and drive systems online.

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

CANOpen based brushless DC motor with position control.

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An integrated approach in a decentralised world. maxon brushless DC motor with internal position controller and encoder.

Particularly suitable for manufacturing lines and process control applications the maxon integrated drive features a maintenance free combination of a 54 mNm 12, 24 and 48V brushless DC motor, 4000qc 3 channel incremental encoder with line driver (complimentary channels) and a full digital position and speed control unit. The position control is offered in two versions. One with internal processor and memory for pre-programming and standalone position control operation. This unit also has CANOpen master functionality. The second version is a CAN slave unit. Multiple integrated drives can then be daisy chained off the first and a complete standalone coordinated multi axis drive network can be configured. Alternatively the slave drives can be connected directly with a PLC or FPGA based master. The motor units are supplied with the powerful EPOS studio tool for easy gain configuration and motor tuning. Standardised IEC 61131-3 simplifies development and reduces costs. Planetary gearheads are available in a piece part system allowing adjustment for required application speed and torque.

Contact maxon motor Australia for further information Ph: +61 2 9457 7477.