As technology iterates and innovates, robots are playing an increasingly important role in human life, whether in medical devices or industrial manufacturing, where intelligent robots can be found. The key to empowering robots to perceive the world and feed back information lies in technological innovations in vision and force perception. Currently, machine vision is relatively well accomplished, supported by high-resolution imaging and mature algorithms. In the area of force perception, which is a more sophisticated test of a robot's ability to operate, the competition is not fully reflected and the market is still a blue ocean.

1. Introduction to six-dimensional force sensors

Force sensors are devices that convert one or more mechanical quantities (tension, pull, pressure, weight, torque, internal stress, strain, etc.) into electrical signals (voltage, current, bus, etc.) using force sensitive elements and conversion elements and processing units. Six-dimensional sensors, on the other hand, are capable of measuring three force components and three moment components simultaneously and are the most complete form of multidimensional force sensors, which are currently used in industrial robots, collaborative robots, medical robots and other applications.

The development of force sensors involves the cross-fertilisation of mechanics, mechanics, materials, metrology and other disciplines, and the barriers are high.

2 Main application scenarios

①Industrial robot collision detection

In order to prevent damage to robots or objects due to excessive interaction during operation, flexible control is necessary to complete these tasks, so collision strength is an important part of active flexible control; on the other hand, many tasks now also require human intervention, and in terms of safety, it is necessary to detect whether there is a collision between the robot and a person, to keep the person as safe as possible, and to allow the robot to recognise the presence of a person so that the work in progress can be stopped if necessary to avoid accidentally injuring people.

②Precision grinding by industrial robots

At present, most domestic manufacturing enterprises use manual or hand-held pneumatic electric tools for grinding, lapping and filing for deburring, grinding and polishing of engine casings, bodywork and other workpieces, which can easily lead to a rise in the defective product error rate and low efficiency, and can lead to problems such as uneven surface roughness of processed products; at the same time, the sparks, dust and noise generated by grinding have a great impact on the physical and mental health of workers The quality of manual grinding needs to be roughly judged from the workers' experience, making the quality of grinding not guaranteed; the lack of skilled labour, low labour efficiency, difficulty in recruiting labour, the continuous rise in labour costs and the poor working environment have prompted the trend of robots replacing manual labour to accelerate development.

③Industrial robot dragging and teaching

Drag teaching technology can be used to teach robots in an intuitive way by directly hand-holding the robot to reach a specified position or move along a specific trajectory, while recording the position data of the teaching process, which can significantly shorten the programming efficiency of industrial robots in the application deployment stage, reduce the requirements for operators, and achieve the purpose of reducing costs and increasing efficiency.


④Medical rehabilitation

The six-dimensional force sensor with micron-level accuracy breaks through the lack or inadequacy of haptic feedback (force feedback) in medical robots, which affects the accuracy, safety and flexibility of surgical operations, and increases the robot's haptic function and sensing of touch, pressure and pull, while also simultaneously detecting the magnitude of force and the strength of haptic sensation during the medical process. This will solve the problem of medical robots' surgical sequelae caused by the lack of haptic functions and the lack of sensing of touch, pull and pressure, and promote the application and development of medical robots.

3 Domestic and international market situation

Six-dimensional force sensors are currently widely used in the fields of industrial fine grinding and medical rehabilitation. Although the domestic market started late, there are many excellent companies in this niche industry. Compared with foreign brands, many domestic products have already met or even exceeded the relevant performance indicators of foreign products, and have more advantages in terms of price and service, therefore, there is a great opportunity to achieve domestic substitution in the future.

4 Conclusion

Force sensors give robots a sense of touch, allowing them to better perceive the world. As the application scenarios of intelligent robots continue to be enriched, six-dimensional force sensors will become an important bridge for future human-robot interaction.