Roboticists from two countries won a joint grant in a competition for the best fundamental scientific projects
Scientists will create robotic systems andmanipulators consisting of links of parallel type based on twisted threads - twisted string actuators, TSA. This will allow 2-3 times to increase the payload of such systems and the accuracy of their management. In TSA-based drives, the thread is attached to the engine on one side, and its second end is attached to a working body or mechanism that moves the payload. As a result of twisting the threads are reduced and set in motion the working body.
This type of drive has a number of uniquethe advantages that make it attractive in the development and design of all kinds of robotic systems are light weight, high developed efforts, accuracy, flexibility in the design and installation.
Igor Gaponov, Head of the Laboratory of Mechatronics, Control and Prototyping of Innopolis University
Most robotic arms withsequential structure using traditional drives, have a relatively low load capacity. Drives in such devices are usually installed in joints - joints, and therefore the "shoulder" of the robot is forced to move the remaining 5-6 drives. As a result, a manipulator weighing, for example, 500 kg is capable of lifting no more than 50 kg of the payload. However, the weight of such manipulators can be significantly reduced while maintaining load capacity due to the use of new drives and links based on TSA. However, experts from the development team plan to increase this figure three times so that the robot weighing 500 kg can lift up to 150 kg of the payload.
Another popular industrial grademanipulators where it is planned to use TSA - devices of the parallel type with a large working range, also called delta robots. They have high speed, but relatively low carrying capacity, which is why multifunctional robotic grips cannot be installed on such manipulators without serious performance degradation. However, the low weight of the TSA allows you to create more flexible and lighter robotic grips on their basis, for example, the motor in this drive can be installed remotely from the gripper - on the basis of the robot, and thus the mass of the brush fixed on the robotic arm will be no more than 200-300 g , unlike most commercial analogues, whose weight is 0.5 kg or more.
Work on the project began in March and will lastuntil the end of 2021. The joint team consists of 13 people. The project from Innopolis University is led by Igor Gaponov, and from KAIST, Professor Ji-Hwan Ryu. A Russian IT university is responsible for the development of the mathematical apparatus and the synthesis of structures based on TSA. By the middle of the second year, scientists plan to complete the development of a control system for such devices and conduct experiments on synthesized mechanisms. KAIST staff will focus on developing an adaptive management system and will develop a system based on passivity. Scientists of the two countries will jointly manufacture prototypes and experiments.
For 2 years, researchers plan to describetheoretical foundations of modeling the statics and dynamics of parallel mechanisms and robots based on TSA, develop methods for obtaining information about the external influences on the robot from the environment without specialized force sensors, classify the designs of such robots and describe their properties taking into account the use of TSA, methods for automated synthesis of systems with desired characteristics, synthesis of prototypes of robots with optimized structure, develop a mathematical apparatus for automatic planning I and optimization of the trajectory of links and robots, as well as adaptive control systems for individual drives on twisted threads and devices based on them.
According to the staff of Innopolis University, onBased on the developed and constructed modules, it will be possible to design devices and systems that will be used in almost all areas of modern technology: industrial manipulators and machine tools, human-machine interfaces, medical robotics, exoskeletons and more. Separate modules based on TSA can be implemented in mobile robots and any other systems where linear drives are needed.