On November 29, the Science and Technology Innovation Board Daily News (edited by Song Ziqiao) reported that on November 28 local time, Tesla's official robot account released a new update: preparing new hands to welcome Black Friday. In the video, Optimus steadily catches the tennis ball thrown towards it and puts it down, with its fingers able to bend relatively flexibly.

The dexterous hand is the most eye-catching feature of Tesla's second-generation Optimus. Tesla engineer Milan Kovac referred to the newly showcased dexterous hand as a "milestone achievement."

Comparing it to the previous generation, Kovac explained that the new hand/forearm has double the degrees of freedom (22 degrees of freedom in the hand and 3 degrees of freedom in the wrist/forearm). Note: Human hands are generally considered to have 27 degrees of freedom, the higher the degree of freedom in the hand, the more complex and delicate movements it can make.

Kovac stated that the above video was completed in real-time in the laboratory through remote operation, and Tesla will soon manufacture robots equipped with new dexterous hands.

Furthermore, the team still has some work to complete by the end of the year, especially around expanding tactile sensor integration (the new generation hand has a much larger surface coverage than the previous one) and achieving finer control through tendons. As all driving devices have been moved to the forearm, this has increased its weight, so the team is figuring out how to reduce the weight of the forearm. An interesting challenge is how to provide fingers and palm with a protective layer with enough softness/ flexibility while not affecting tactile sensors.

Musk replied below his post: "The Optimus team did a great job."

The 22-degree dexterous hand finally emerges after much anticipation.

The previous generation of Optimus' dexterous hand ontology contains 11 degrees of freedom, also focusing on the flexibility of the forearm. Compared to the first-generation Optimus prototype, which struggled with simple tasks, the Optimus equipped with an 11-degree-of-freedom dexterous hand can complete tasks such as folding shirts and sorting items in factories.

The 22-degree-of-freedom dexterous hand is finally here. In May, the Optimus team released a progress video showing the robot categorizing batteries and walking around the office. Musk commented below the video, revealing for the first time that Optimus' hands will soon have 22 degrees of freedom.

At Tesla's shareholder meeting in June, Musk reiterated Tesla's goals (April 23, 2024, Musk stated during the Q1 earnings call that by the end of this year, Optimus devices are expected to perform a series of useful tasks in the factory, with the company's goal of selling these robots externally by the end of 2025). The plan is to start small-scale trial 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. Once again, he mentioned a key improvement for Optimus—the hands will have 22 degrees of freedom, capable of playing the piano and even the guitar.

At the 'werobot' event held by Tesla in October, the 22-degree-of-freedom dexterous hand made its debut, showcasing new postures of outward and inward gestures on top of flexion/extension movements. The cable-driven structure of the dexterous hand is distinct, with actuators placed externally in the forearm, allowing flexible wrist movements.

CITIC Securities stated that this aligns with their expectations for Tesla's dexterous hand using the 'hollow cup + lead screw + rope drive' solution. The 22 degrees of freedom consist of 5 degrees per finger and 2 at the wrist, closely mimicking the structure of human finger joints, which have over 1 degree of freedom at the lowest joint.

The dexterous hand is a core component of humanoid robots, with companies both domestically and abroad actively developing their own solutions.

The dexterous hand is currently one of the core components of humanoid robots, and mainstream manufacturers tend to develop their own solutions, such as Tesla (Optimus), Apptronik (Apollo), UBTECH (Walker S), SGVA (Expedition A1), and Sanctuary AI (Phoenix).

Huaan's research report points out that the performance and cost of dexterous hands are jointly influenced by their three core components—drive, transmission, and sensing devices. With advancements in robot technology, the upgrading of dexterous hand degrees of freedom is accelerating, moving towards higher integration and intelligence. According to incomplete statistics from the 'Star Daily',

On October 16th, the information from the State Intellectual Property Office shows that Zhiyuan Robotics applied for a patent named 'Dexterous Thumb, Dexterous Hand, and Robot' in June this year. The patent abstract indicates that this application relates to the field of robotics, specifically involving a dexterous thumb, dexterous hand, and robot, addressing the issue of a dexterous thumb with 3 degrees of freedom being unable to simultaneously consider joint decoupling and dimensions. It is worth mentioning that in the new product released by Zhiyuan Robotics in August, the dexterity of the hand reaches 19 degrees, with the active degrees of freedom increasing from 6 in the previous generation to 12.

In the first half of this year, Xingdong Jiyuan launched the independently developed Dexterous Hand Xhand, which has 12 active degrees of freedom, adopts a fully driven scheme, and also incorporates tactile sensors at the fingertips.

Figure AI unveiled the second generation humanoid robot Figure02 in August this year, equipped with the fourth-generation mechanical hand. According to information publicly available on its official website, Figure02's dexterous hand has 16 degrees of freedom, stating 'equivalent load capacity to that of humans, capable of grasping objects up to 25 kilograms.'

1X Technologies, a startup funded by OpenAI, introduced the NEO test version of a humanoid robot designed for household use in early September this year, with 20 degrees of freedom in the hands and the ability to lift objects weighing more than twice its body weight.

Sinolink Securities previously released a research report stating the differences in Tesla's third-generation Dexterous Hand compared to the second generation: (1) the hand has increased degrees of freedom from 11 to 22, which may correspondingly increase the number of motors from the original 6 to 13-17; (2) the drive unit has been relocated from the hand to the wrist.

Sinolink Securities stated that based on functionality and long-term goals, the trend towards humanoid hands resembling human hands is inevitable. Taking Tesla's Dexterous Hand as an example, the institution analyzed the industry chain elasticity brought about by the increase in degrees of freedom.

Regarding the drive unit, it is expected that hollow cup motors and brushless grooved motors will become mainstream, assuming a quantity of around 13-17 units per hand, with the current value of a pair of hands ranging from 3.4 to 0.153 million yuan.

In terms of the transmission unit, there is currently a critical transition from tendon ropes to screw rods. Assuming 13-17 sets per hand, the current value of a pair of hands ranges from 5.5 to 0.13 million yuan.

On the sensor device, the tactile sensor is the most valuable link in terms of quantity, with about 5 sets for single-handed use and a value of about 1351 yuan for double-handed use.