Change is inevitable. Sensor technology continues to advance. And robots keep evolving. Each one impacts the other, but which one—sensors or robots—is making the biggest splash? With robotics playing such a pivotal role in the future of discrete manufacturing, we asked a seasoned panel of industry for their insights and predictions on the role of robots.
Q: Can you please address robot’s impact on non-vision sensing, or the effect that sensors have had on the surge in robotics?
Henry Menke: Imagine the state of robotics in a world without sensors. Robot operations would be restricted to programmed motions only. Without the benefit of sensor inputs reporting process status, dynamic condition-based changes in operation could not be implemented. A sensor-less robot running open loop could not modify its operation in response to changes or variations in process conditions, such as part size variability.
Sensors enable an increase in the complexity of tasks robots can handle, without requiring a corresponding increase in the complexity of the robot itself. Sensors on a robot end effector do just what their name implies: they give the robot various forms of sensation—presence, position, force, temperature, color and pressure for the robot's end-effector tooling and for the fixed tooling and components that it is working with. The robot can be programmed to close its operational loop using sensors to detect or measure the independent process variables, as well as detect or measure the dependent process variables under the control of the robot itself.
As always, robot payload is a concern. As sensors are added, especially to smaller robots, it’s important to minimize the mass of the sensors that impacts the net payload capacity of the robot. The rise of miniaturization in sensor technology is enabling smaller and lighter robots to also be equipped with sensor packages to make them more flexible and productive, without excessive weight driving the application into the next larger robot payload class.
Corey Ryan: Integration of additional sensors is critical to ensuring safety in cases where a collaborative robot system is developed with standard robots. Standard industrial robots are typically only designed with collision detection to prevent damage to the robot but still generate forces well in excess of those required for injury. Some robots designed for human-robot collaboration (HRC) are capable of carrying higher payloads and moving quickly in order to maximize throughput when people are not in the working range, but at full speed and payload they can easily exceed safe limits. In order to safely implement speed and separation monitoring, as defined by the ISO standards, sensors have to be used to determine the presence of people in the working range of the robots.
Garrett Place: One of the primary advancements here is optical sensing, or photo eyes. These devices have become smaller in size, but no less powerful. The small size allows them to be integrated on the end of arm tool or, because of their precise long range, out of the way of the robot travel. Both advancements open up new opportunities for robot integrators.
David Arens: Non-vision sensing is used to collect outside data that is not always available to a machine monitoring approach with vision. There are combination sensors that are designed for six axes of acceleration, gyroscope for monitoring of up and down, compensation temperature monitoring for the circuit and for the device it is mounted to, GPS for world coordinate location data and built-in data logging and rules alarm monitoring capability. All of this data can be used to monitor the health of the production, the health of the product as it is being produced and the quality of the product as it is being manufactured, lowering the amount of bad product produced and increasing the amount of first-build good product being sent out the door.
Scott Mabie: With the improvement in sensor technology and reduction in cost of sensor technology, the number of everyday applications has grown. Sensors are now becoming a very standard part of all automation from part presence and quality checks to production diagnostics, as well as on equipment for active health assessments.
Allan Hottovy: Sensors are the robot's senses and a fundamental requirement in any robotics system. Standardized sensor products that work across multiple platforms have helped to speed up the use of robotics. The simpler and easier they are, the more people will use them.
When builders set and built to a simple form/fit/function spec and couple this with international manufacturing standards, you are guaranteed a system that can be shipped throughout the world, pass local regulations and is easy to understand and maintain with local technical and component support. This trend of standardized components to lower total cost of ownership has been a big driving force.
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