AUGUST, 20219 developed for the automotive industry for ABS and traction control systems. In their original form, the Hall-effect sensors didn't have the accuracy required for precision robot controls. However, by combining the output of several Hall-effect sensors through sophisticated signal processing algorithms, POSITAL-FRABA has achieved resolutions as high as 17-bits, with accuracies and jitter good enough for closed loop control of high-speed dynamic control systems.KIT ENCODERS­ALTERNATIVE PACKAGING FOR ROTARY POSITION FEEDBACKTraditionally, most encoders have been sold as self-contained units with their own housing, shaft and shaft bearing. Kit encoders are basically the core measurement elements of magnetic encoders, offered as separate components. In this form, they can be easily installed inside the casings of motors or other machines, saving both space and cost. These rotation sensors can provide both commutation signals (essential for brushless DC motors) and accurate rotary position measurements.DATA COMMUNICATIONSAll of the sensors, drives, (motors) and actuators that make up a robot system need to communicate with the controller hardware. Simple point-to-point wiring can be adequate for basic robots, but as the number of connections increases, it becomes increasingly attractive to use a network-style communications system. So-called fieldbus systems use a shared wiring backbone that simplifies wiring and controller interfaces. Fieldbus technologies date from latter decades of the last century and were designed for individual machines, work cells or small factories with a limited number of nodes.Ethernet technology has been adapted for industrial use. It is more scalable than fieldbus, offering opportunities for higher levels of system integration across the entire factory complex. A limitation or `classical' Ethernet is that the instantaneous delivery of data packets cannot be guaranteed. This can be a serious problem for industrial processes where potentially dangerous situations need to be identified and responded to in near real-time. Several enhanced Ethernet variants have been developed for industrial use that provides priority routing for critical alarm messages.IN SUMMARY...Sensors provide robots (and many other `smart' machines) with an important element of `awareness' of their position in space and of their relationship to any objects or people who share this space. As sensors become more capable­more accurate, reliable and sensitive, we will see them enabling more versatile and competent automatic machines. Much of the enhanced capabilities are coming about through a combination of faster and more powerful hardware (especially microcontrollers) and more intelligent software. The future is exciting­and coming at us very quickly! Reliabilityis a must,of course,even whenthe robotoperates ina harsh, wet,dirty or hotenvironmentChristian Fell
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