CoboSafe: Force Measuring Systems for Collaborative Robots
In any human-robot collaboration (HRC) without separating protective equipment, collisions between humans and robots cannot be completely ruled out. The permissible limit values for force and pressure in accordance with ISO/TS 15066 must be observed as they ensure the safe operation of HRC work areas. Regarding occupational safety arise diffrent requirements on work spaces of collaborative robots. The force and pressure measurement system CoboSafe meets all the requirements that are necessary to verify the adherence of limit values and is tailored for every application area. The key to this is the combination of force- and pressure measurement.
Force Measurement: CoboSafe-CBSF
For each of the nine spring constants according to ISO/TS 15066, one aluminum made calibrated force transducer is immediately available and ready for measuring without any further preparation. The heart of the force transducer is the Piezo force sensor with linear-guided measuring mechanism which guarantees optimum measuring accuracy and reproducibility. The force gauge is equipped with integrated electronics for the evaluation and storage of the values measured. The storage capacity is up to 100 single measurements. The transient and quasi-static values are represented via the display and the force curve is rendered graphically. Data are transferred wireless or alternatively by USB interface. In this way, the force transducers are very easy to position and the data is immediately visible on the PC or another external display screen.
Depending on the requirement and objective, a set with up to nine force transducers with different spring constants can be set up. The combination of the spring constants (K2) with one of the additional damping elements (K1) allows the biofidel properties to be configured according to ISO/TS 15066 and DGUV (German Social Accident Insurance) information „FB HM-080“. As a component for pressure measurement are either a simple scan pressure measurement method or a more demanding pressure measu-rement method based on electronic film sensors available.
Safely comply with limit values in non-priority speed-oriented applications
The CBSF-75 Gripper allows the verification of static and dynamic gripper clamping forces on collaborating robots
For pressure measurement either a simple set (CoboSafe-Scan) based on pressure measuring foils or the more demanding pressure measuring method (CoboSafe-Tek) based on electronic foil sensors are available.
The set CoboSafe-Scan is based on Fujifilm Prescale measurement films. It records the pressure distribution and the maximum pressure. The films react to the pressure and display the pressure distribution. The pressure force is determined by the intensity of the discolouration of the pressure measuring films, to an accuracy of ±10%. Using a scanner and a calibration-sheet, the pressure image is imported into the Software CoboSafe-Vision and evaluated automatically. The imported pressure film is converted into pressure values and the pressure image and maximum pressure are displayed as a result. The set includes a scanner, a calibration-sheet and films.
The set CoboSafe-Tek supplies via electronic film sensors next to maximum pressure and pressure distribution also a pressure curve measurement.
The system is particularly suitable for applications which require very detailed results. The collision pressure is recorded as a “film”. By means of synchronisation on the force curve, the pressure values and the pressure distribution can be determined and visualized for the required transient and static pressure. The system will show all four measured values according to ISO/TS 15066. It comprises various film sensors, a handle for picking up the films and a hub (inter-face). The film sensors can be reused several times and consist of ultra-thin circuit boards with circuits and pressure sensitive cells.
The software CoboSafe-Vision visualizes the force curves measured and the pressure images. It calculates and determines the values for the transient and quasi-static forces. An assessment of the pressure image is possible by means of the two and three-dimensional representation as well as by using the filters. Individual reporting is also possible, such as csv-export.