The 22-degree dexterous hand "suddenly comes out"
The previous generation dexterous hand on Optimus contained 11 degrees of freedom, also focusing on the flexibility of the forearm. Compared with the first generation Optimus prototype, which had difficulty performing simple tasks, the Optimus equipped with an 11-degree dexterous hand can complete tasks such as folding shirts and sorting items in the factory.
The 22-degree dexterous hand is also "suddenly revealing itself." In May, the Optimus team released a progress video showing the robot categorizing batteries and walking in the office. Musk commented below the video, revealing for the first time that Optimus's hands will soon have 22 degrees of freedom.
At Tesla's shareholder meeting in June, Musk reiterated Tesla's goals (during the first quarter earnings conference call on April 23, 2024, Musk stated that by the end of this year, Optimus devices are expected to perform a series of useful tasks in the factory, and the company's goal is to sell these robots to the public by the end of 2025). The plan is to start small-scale production of Optimus robots by the end of 2024, with an estimated production of thousands to tens of thousands throughout 2025 for internal use and training. He once again mentioned a key improvement of Optimus - the hands will have 22 degrees of freedom, "it can play the piano, and even the guitar."
At the "werobot" conference held by Tesla in October, the 22-degree dexterous hand made its debut, demonstrating new postures of extension and retraction on the basis of bending/stretching. The dexterous hand's prominent line-driven structure, with actuators located externally in the forearm, allows flexible wrist rotation.
This aligns with the expectations for Tesla's dexterous hand, using the "hollow cup + screw + rope drive" solution. The 22 degrees of freedom consist of 5 fingers with 4 degrees of freedom each + 2 automatic degrees at the wrist, imitating to the maximum extent the structure of human fingers with over 1 degree of freedom at the lowest joint.
The dexterous hand is a core component of humanoid robots, actively self-developed by global enterprises.
The dexterous hand is already one of the core components of humanoid robots, and mainstream humanoid robot manufacturers prefer to self-develop, such as Tesla's (Optimus), Apptronik (Apollo), YoubiXuan (Walker S), Zhiyuan (Expedition A1), and Sanctuary AI (Phoenix).
The performance and cost of the dexterous hand are jointly influenced by its three core components - drive, transmission, and sensing devices. With the advancement of robot technology, the dexterous hand's degrees of freedom have been upgraded rapidly, moving towards higher integration and intelligence. Equipped with the fourth generation of machinery hands, Figure02's dexterous hand has 16 degrees of freedom, known for having 'a load capacity equivalent to that of humans, capable of gripping objects weighing 25 kilograms.'
1X Technologies, a startup invested in by OpenAI, introduced a test version of the humanoid robot NEO designed for household use in early September of this year. The hand has 20 degrees of freedom and can lift objects weighing more than twice its body weight. The changes in Tesla's third-generation dexterous hand compared to the second generation are: (1) the hand has increased its degrees of freedom from 11 to 22, potentially increasing the number of motors from the original 6 to 13-17; (2) the drive unit's mounting location has been shifted from the hand to the wrist.
Based on functionality and long-term goals, the trend of dexterous hands moving towards humanoid hands is inevitable. Taking Tesla's dexterous hand as an example, the institution analyzed the industrial chain elasticity brought about by the increase in degrees of freedom:
In terms of drive devices, it is expected that hollow cup motors and brushless grooved motors will become mainstream, assuming a single hand requires about 13-17, with the current value of a pair of hands ranging from 3.4 to 0.153 million yuan;
In terms of transmission devices, we are currently at a crucial point of transition from tendons to screw threads, assuming a requirement of 13-17 sets for a single hand, with the current value of a pair of hands ranging from 5.5 to 0.13 million yuan;
Regarding sensing devices, tactile sensors represent the most valuable link, with an approximate requirement of 5 sets per hand, and a value of around 1351 yuan for a pair of hands.