Exploring the Versatile World of Collaborative Robots: Types of Cobots in a Nutshell


Have you ever wondered how collaborative robots can safely work alongside humans? The answer lies in the different types of cobots available in the market.

Four types of cobots to be precise: Power and Force Limiting, Safety Rated and Monitored Stop, Speed and Separation, and Hand Guiding. Each type adheres to the strict standards set by the ISO Cobot Safety Guide, ensuring safe human-robot interaction.

But don't think that these cobots are all alike. The Power and Force Limiting cobot sets itself apart with its advanced sensors that allow it to use standard industrial robots while maintaining safety. Meanwhile, the other three cobots bring their own unique features to the table, making them more suitable for specific needs.

Discover the distinguishing features of each cobot type and determine which one will best meet your requirements.

1. Power and Force Limiting Cobots:

Power and force limiting cobots are the safe choice for human-robot collaboration. Equipped with advanced collision sensors and physical safety features, these cobots automatically stop operation upon contact with humans, minimizing the risk of injury. No additional safety equipment, such as vision systems or barriers, are required when a risk assessment confirms their safe use.

But, it's not all sunshine and rainbows with these cobots. They may be slower, smaller, and less powerful compared to the other three cobot types, and may struggle with heavy payloads and precision tasks.

Despite these limitations, power and force limiting cobots still stand out in the collaborative robot landscape, being one of the four main categories defined by their safety functionality. They offer a cost-effective solution without sacrificing safety, making them a suitable option for many applications. This includes:

Joint Sensing:

Joint sensing cobots use innovative technology to monitor the forces applied to their bodies through their joints. This allows them to be sensitive to human-cobot interaction and adjust their movements accordingly. These cobots come in two forms: those that use force-torque sensors and those that rely on the current of their motors. The former is highly precise, providing real-time measurements of the forces applied to each joint, while the latter uses the current draw of each motor to determine the forces being applied.

One of the key advantages of joint sensing cobots is their ease of use. These cobots are designed to be simple and intuitive, making them an ideal choice for human-cobot interaction. They can be programmed to follow complex paths, repeat specific actions, and even make real-time adjustments based on the forces being applied. This makes them ideal for tasks that require precision, flexibility, and human-like dexterity.

Whether you're a small business owner looking to automate a manual process, or a large manufacturer looking to optimize your production line, joint sensing cobots are a highly effective solution. With their ability to adjust their movements in real-time and respond to human interaction, they provide the perfect balance of safety and efficiency.

Skin Sensing:

Skin-sensing cobots are a type of collaborative robots equipped with tactile sensors that monitor forces acting on their body. These sensors detect potential impacts and send signals to the cobot to stop its movement, avoiding collisions and ensuring safety for human-robot interaction.

Unlike joint-sensing cobots, skin-sensing cobots require specialized training to operate effectively, but they are widely regarded as safe and are widely used in applications where precise and delicate handling is required.

For instance, in industries such as electronics, pharma and food and beverage, skin-sensing cobots are often preferred due to their advanced safety features and ability to handle delicate tasks with great precision.

Force Sensor Base:

Force Sensor Base cobots are a versatile option for those who need a powerful cobot that can handle heavy loads but still maintain a high level of sensitivity for safe human-cobot interaction.

They offer a unique combination of strength and safety, with the ability to detect and respond to forces applied to the body through the use of advanced force sensors.

However, compared to joint-sensing cobots, these cobots require more technical expertise to calibrate and adjust their settings for optimal performance.

Inherently Safe:

Inherently Safe cobots are designed with safety as their top priority, hence their name. These cobots are built with limited payload capacity, which minimizes the potential risk of harm to human workers.

However, the end-of-arm tooling used with these cobots, such as a welding tool, could affect the safety level. These cobots are an excellent choice for low-risk tasks where human-robot collaboration is required, but they may not be suitable for more heavy-duty applications.

To read more about cobots.

Updated 03.02.23