During the handling of loads, hoists are often used that lift defined weights and require the operator only to move them horizontally. This means however that the vertical movement must be controlled by the operator by means of actuators. If this operation is too difficult or complicated, the operators' acceptance of the hoists drops, and in extreme cases they may even revert to handling loads entirely manually.
A simple and intuitive control system is one that detects the operator's movement directly rather than via additional control elements, and does not require control commands to be entered.
No relevant ergonomics standards for balancers are known.
The Technical Report ISO/TR 22100-3 describes how ergonomic principles can be applied during the risk reduction process according to ISO 12100 and how ergonomics standards can be applied to machinery. It helps designers take decisions with respect to ergonomics during the machine design process and can also be used when no relevant type C standards are available.
Manipulators can be set to a specific weight in order to counterbalance it. This enables the load to be moved vertically without major force exertion. Alternatively, they can be equipped with a control that enables the height of different weights to be adjusted. This enhances their flexibility, but also constrains the user, who in this case must still be able to reach and operate the controls in addition to safely holding the load and the manipulator.
Where the height is controlled by detection of hand force, sensors are integrated directly into the manipulator handle. One sensor detects when a hand has enclosed the handle: only then does it enable the system, thereby preventing unintended movement. A second sensor detects forces applied by the hand in the vertical plane and controls the motor accordingly in assisting these movements. This arrangement supports intuitive and natural movement during work and simplifies operation. (See also EN 13557:2009, Section 5.1; EN 14238:2010, Section 5.5)