FORCE ACTION - HOW ELECTRIC MOTORS SUPPORT HUMAN STRENGHT
The success of pedelecs or E-Bike systems is based on supporting people in their daily lives. An electric motor helps people ride their bicycles based on an initial muscle strength. The E-Bike can thus help people who are not able to ride a bicycle due to their physical condition, as well as a group of cyclists who are able to cycle further distances due to this additional support.
How electric drives bring man and machine together
However, this very everyday application is only the beginning of the breakthrough in power assistance by electric drives and of this new automation. Man and machine grow closer together and merge to form a unit that acts together. The prerequisite for such a symbiosis is the recognition of human signals in order to initiate targeted force support. Not so long ago, KUKA introduced a robot that supports people in production line activities in a very confined space. This very close interaction between man and machine offers many possibilities for facilitating various tasks for people and thus protecting their own muscle strength. The close relationship between man and machine requires a certain degree of functional safety in order to avoid accidents.
The implementation in practice
More and more companies are coming onto the market with ideas to bring this muscular strength support into society with various applications. For example, there is a special backpack that can be carried and connected to the arms. Its control system recognizes movements of the human arms and supports the arms in their movements in a targeted manner. This would help, for example, to reduce the effort in overhead movements; further examples are e.g. revolving doors as, by touching the door, a reaction of the drive unit is already triggered to bring the door and the person inside it to the other side. Many other ideas range from the electrification of baby carriages (supported
by the pushing impulse of the parents) to the walking robot.
Sensors as a link between men and machines
All these requirements have one thing in common. You need a sensor that captures the information of the person you are interacting with. On the one hand, this can be achieved with optical systems. However, these have the disadvantage that they are not sensitive enough to detect even very small impulses. A good example to illustrate this is the attempt to grip a glass of water only on the basis of optical information. No robot is able to do this. Either it grabs firmly and damages the glass or it grabs too little and the glass slips through the hand. Even humans are unable to grasp a glass of water without the sensors on their fingers.
Sensitive sensors
To avoid this problem, it is necessary to use sensors that are able to detect the smallest axial forces, bending forces or torques. Magnetic Sense has developed a technology that can detect the smallest mechanical forces on ferromagnetic constructions. With this torque sensor technology it will be possible in the future to meet this challenge. The first application, torque measurement in E-Bikes, is already in a development phase in which the first units are produced. Miniaturization and implementation in these applications is already well advanced.
