Cobotic Sensors Challenges

In this exclusive interview, Cecelia Zhen, HBK OEM Custom Sensor design engineer, explore the transformative power of cobot sensors and their role in reshaping human-machine interaction across various industries. From healthcare to agriculture, witness how cobots are revolutionizing industries and elevating productivity to new heights.

Safety takes center stage as we unravel how state-of-the-art technology and Finite Element Analysis optimize cobot sensor reliability. Unveil the key requirements essential to sensor data sheets, and discover the techniques safeguarding sensors from environmental challenges.

Curious about strain gauges in cobotic sensor systems? Cecelia shed light on their purpose and the precise data they provide during cobot operations. Experience engineering behind cobot sensor designs, crafted to adapt and flexibly tackle diverse tasks.

Don't miss this exclusive interview with Cecelia, where the future of robotics and custom sensor design awaits. Your curiosity is the key to unlocking the limitless possibilities ahead!

What are collaborative robots, and how do they differ from industrial robots?
Collaborative robots, or cobots, have been a game-changer in various industries. They are designed not only to get the tasks done efficiently, but also to make the work environment inclusive and interactive, where humans and machines work together to achieve better outcomes.
What sets cobots apart from traditional industrial robots is their ability to work safely alongside humans without the need for safety barriers. Equipped with built-in safety features and sensors, they smoothly switch tasks and adapt to changing conditions, intelligently adjusting their actions when working near people. This ensures a safer and more efficient collaboration between humans and cobots.

Which industrial sectors are currently using collaborative robots successfully?
Cobots have found successful applications in various industrial sectors. For instance, healthcare professionals utilize cobots for medication dispensing, patient care, and lab assistance to enhance efficiency and patient outcomes. In manufacturing, they are widely used for assembly, pick and place, packaging, and quality inspection tasks. The electronics industry relies on cobots for circuit board assembly and testing. Additionally, in metalworking, cobots play a significant role in processes such as CNC machine tending and metal fabrication.

What is the operating concept of a cobotic system?
The concept of a cobotic system is all about the robot and its human operator working together in the same workspace. This system comes with important features like safety measures, adaptability, easy programming with hand-guiding, and limits on power and force. These features ensure that humans and robots can interact safely and effectively, making the work environment productive and safe.

What are the main challenges associated with using sensors in collaborative robots (cobots)?
Designing cobot sensors poses several challenges, including accurate safety detection of human presence and objects, maintaining reliable and durable functioning despite environmental variations, achieving cost-effectiveness, addressing regular maintenance needs, and providing flexibility for various applications.

How do collaborative robots (cobots) interact with their operators?
Cobots are purposefully crafted to promote seamless and secure collaboration with operators. They come equipped with safety features such as force and torque sensors, collision detection, and compliance control, which enable them to adjust their movements to prevent accidents during interactions. Depending on their capabilities, cobots use various methods to interact with operators. Some cobots support hand guiding, where operators can physically demonstrate tasks without complex coding. Additionally, user-friendly programming interfaces, like visual interfaces and drag-and-drop programming, simplify task teaching for operators with minimal coding experience.

How can cobot sensors address safety concerns when working alongside humans?
In a cobot system, various safety sensors are integrated, including proximity sensors for collision detection, force/torque sensors, vision systems, and speed monitoring. For instance, if the cobot accidentally collides with an operator or an obstacle, the sensors detect the sudden increase in force and trigger a response mechanism. The cobot's programming interprets this sensor data and can take immediate preventive action, such as adjusting its movements, slowing down, or coming to a complete stop to avoid causing any harm or damage. This responsiveness allows the cobot to work safely and collaboratively with humans, reducing the risk of accidents and injuries in shared workspaces.
 

What role does Finite Element Analysis (FEA) play in optimizing the design of cobot sensors?
Finite Element Analysis (FEA) is a simulation technique used to analyze the structural behavior of objects under various conditions.
FEA is a valuable tool for engineers to optimize sensor design. It simulates the sensor's behavior under different conditions, identifying stress points and weak areas. Engineers can quickly explore multiple design options and select the appropriate material for a robust design. By simulating real-world situations, FEA enhances the sensor's performance and reliability, ensuring it can handle tasks safely and efficiently.

What are the key requirements typically included in a sensor data sheet for cobots?
A sensor data sheet for cobots typically includes information on physical specifications, measurement range for forces or torque, output sensitivity, accuracy, repeatability, hysteresis, linearity, creep, operating and storage temperature ranges, temperature coefficients of sensitivity (TCS) and zero (TCZ).

How can sensors for cobots be protected from environmental challenges such as temperature, pressure, and corrosive fluids?
During the design process, engineers analyze the application's requirements and choose suitable coatings for the sensors. These coatings protect the sensors from harsh conditions like high temperatures, pressure, and corrosive fluids. IP65 and IP67 are most common ingress protection (IP) ratings for cobots. These ratings indicate the level of protection the cobot has against the ingress of dust and water. This ensures that the cobot sensors perform reliably and last long in their intended working environments.

What is the purpose of strain gauges in cobotic sensor systems?
Strain gauges are used to measure the mechanical deformation or strain in materials. When a force is applied, the sensor's material deforms, causing the strain gauge's length and shape to change. As a result, the resistance of the strain gauge changes in proportion to the applied strain. This change in resistance is then measured and converted into an electrical signal, providing accurate data on the forces experienced by the cobot during its operation.

What factors contribute to the reliability of cobot sensors?
First, it's important to choose the appropriate materials and have a robust design to meet the requirements. Regular calibration and maintenance play a big role in ensuring accurate measurements over time. To avoid damage, it's essential to protect the sensors from dust, moisture, and corrosive substances. Having backup systems or redundant components is a smart way to provide extra safety in case something goes wrong with one part of the sensor.

How can cobot sensors be designed to ensure flexibility in their use for different tasks?
Design engineers can enhance flexibility by creating scalable sensors suitable for different-sized cobots and capacities. They can also incorporate a universal mounting interface for seamless integration into various cobot systems and applications. If possible, they can create multi-functional sensors with different modes of operation, eliminating the need for separate sensors and simplifying the cobot system.