In recent years, quadruped bionic robots have emerged as a focal point in robotics research due to their high mobility and adaptability in uneven and complex environments. These bionic robots, often referred to as “robot dogs,” demonstrate significant potential in military applications such as reconnaissance, patrol, and material transport, while also gaining attention in civilian sectors like industrial inspection, rescue operations, and entertainment. The growing investment in this field has heightened interest in the future development of quadruped bionic robot technology. This study leverages patent data to analyze global innovation trends, providing insights into the current state and future directions of quadruped bionic robot technology. By examining patent applications from 2005 to 2024, we aim to uncover key technological advancements and offer guidance for further research and development in bionic robots.
The analysis is based on a comprehensive dataset of 3,520 patents related to quadruped bionic robots, retrieved from the INCOPAT patent intelligence platform covering the period from January 1, 2005, to November 30, 2024. The search strategy combined keywords and International Patent Classification (IPC) codes, followed by manual screening and indexing to ensure relevance. This dataset allows us to explore global trends, regional distributions, and major innovators in the field of bionic robots. We focus on critical aspects such as leg technology, control methods, and driving mechanisms, which are essential for enhancing the performance of these bionic robots. The findings highlight the dominance of electric drive systems and the rising importance of intelligent control algorithms, shaping the future of quadruped bionic robots.
To understand the global activity in quadruped bionic robot technology, we first analyzed the annual patent application trends over the past two decades. The data reveals distinct phases of development, from initial exploration to rapid growth and maturation. As shown in Table 1, the number of patent applications has fluctuated, with significant increases starting in 2014, indicating a period of technological acceleration. This surge aligns with breakthroughs in bionic robot design and expanding market demands. The decline in applications in 2023 and 2024 is likely due to delays in patent publication, rather than a reduction in innovation. Overall, the trend underscores the sustained interest and investment in advancing quadruped bionic robots.
| Year | Number of Patent Applications |
|---|---|
| 2005 | 26 |
| 2006 | 19 |
| 2007 | 28 |
| 2008 | 33 |
| 2009 | 29 |
| 2010 | 45 |
| 2011 | 42 |
| 2012 | 59 |
| 2013 | 66 |
| 2014 | 117 |
| 2015 | 82 |
| 2016 | 93 |
| 2017 | 160 |
| 2018 | 180 |
| 2019 | 253 |
| 2020 | 318 |
| 2021 | 456 |
| 2022 | 446 |
| 2023 | 428 |
| 2024 | 228 |
The geographic distribution of patent applications for quadruped bionic robots highlights China’s leading position, followed by the United States, Japan, Spain, and the World Intellectual Property Organization (WIPO). China’s dominance, with 2,365 applications, reflects strong governmental support and policy initiatives, such as the “Made in China 2025” strategy and subsequent robotics development plans. These policies have fostered a favorable environment for innovation in bionic robots, driven by diverse geographical needs for applications in military and civilian sectors. The United States, with 301 applications, maintains a robust presence due to its historical investment in robotics and artificial intelligence, while Japan and Spain show steady contributions. This distribution indicates a competitive global landscape for bionic robot technology, with China poised to influence future directions.
| Region | Number of Patent Applications |
|---|---|
| China | 2365 |
| United States | 301 |
| Japan | 235 |
| Spain | 103 |
| WIPO | 96 |
| South Korea | 69 |
| France | 63 |
| United Kingdom | 63 |
| Germany | 27 |
| India | 27 |
| Others | 209 |
Within China, patent applications are concentrated in provinces and municipalities with strong academic and industrial foundations, such as Guangdong, Zhejiang, Beijing, Jiangsu, Shandong, and Shanghai. These regions benefit from rich university resources and supportive policies, including specialized robotics industrial parks and innovation bases. This internal distribution underscores the localized efforts to advance bionic robot technology, contributing to China’s global leadership. The concentration of patents in these areas suggests that collaborative ecosystems between academia and industry are crucial for driving innovation in quadruped bionic robots.
An analysis of the main technological branches in quadruped bionic robot patents reveals significant growth in leg technology and control methods, while tail and spine technologies remain relatively stable with fewer applications. Leg technology, which encompasses drive systems and structural design, is central to the mobility of bionic robots. Control methods have evolved with the integration of machine learning and artificial intelligence, enhancing the autonomy and adaptability of these bionic robots. The limited patent activity in tail and spine technologies presents an opportunity for innovators to explore these areas, as they can impact overall motion performance. For instance, spine designs in bionic robots include rigid, passive, and active forms, each influencing stability and flexibility. We anticipate that future developments will focus on optimizing leg designs with new materials and efficient transmission systems, while control algorithms will become more sophisticated for improved environmental interaction.
| Year | Leg Technology | Control Methods | Tail Technology | Spine Technology |
|---|---|---|---|---|
| 2010 | 15 | 10 | 2 | 3 |
| 2011 | 18 | 12 | 1 | 2 |
| 2012 | 22 | 15 | 3 | 4 |
| 2013 | 25 | 18 | 2 | 3 |
| 2014 | 30 | 22 | 4 | 5 |
| 2015 | 35 | 25 | 3 | 4 |
| 2016 | 40 | 30 | 5 | 6 |
| 2017 | 50 | 35 | 4 | 5 |
| 2018 | 60 | 40 | 6 | 7 |
| 2019 | 70 | 45 | 5 | 6 |
| 2020 | 85 | 55 | 7 | 8 |
| 2021 | 100 | 65 | 6 | 7 |
| 2022 | 120 | 75 | 8 | 9 |
| 2023 | 130 | 80 | 7 | 8 |
| 2024 | 110 | 70 | 6 | 7 |
Key technologies in quadruped bionic robots include leg drive methods and joint structures, which directly affect performance metrics like speed, load capacity, and energy efficiency. Drive methods are primarily categorized into electric, hydraulic, and pneumatic systems. Electric drive has gained prominence due to advancements in motor technology, particularly in load density, which we define as the torque output per unit volume or mass. The load density $\rho$ can be expressed as:
$$ \rho = \frac{T}{V} $$
where $T$ is the torque and $V$ is the volume. Higher load density enables bionic robots to achieve greater power in compact designs, improving mobility and adaptability. Hydraulic drive, while offering high force and torque, suffers from complexity and maintenance issues, whereas pneumatic drive remains niche due to limited application in bionic robots. As shown in Table 4, electric drive patents have surged since 2014, outpacing hydraulic and pneumatic drives, indicating a shift toward more efficient and environmentally friendly systems. This trend is expected to continue, with electric drive dominating future markets for bionic robots, potentially complemented by hybrid approaches combining multiple drive methods.
| Year | Electric Drive | Hydraulic Drive | Pneumatic Drive |
|---|---|---|---|
| 2010 | 10 | 8 | 2 |
| 2011 | 12 | 9 | 1 |
| 2012 | 15 | 10 | 3 |
| 2013 | 18 | 12 | 2 |
| 2014 | 25 | 15 | 4 |
| 2015 | 30 | 18 | 3 |
| 2016 | 35 | 20 | 5 |
| 2017 | 45 | 25 | 4 |
| 2018 | 55 | 30 | 6 |
| 2019 | 65 | 35 | 5 |
| 2020 | 80 | 40 | 7 |
| 2021 | 95 | 45 | 6 |
| 2022 | 110 | 50 | 8 |
| 2023 | 120 | 55 | 7 |
| 2024 | 100 | 48 | 6 |
Leg joint structures in quadruped bionic robots are another critical area, with serial and parallel configurations being the most common. Serial structures allow for simple control and precise motion, making them suitable for applications requiring accuracy. In contrast, parallel structures distribute loads across multiple actuators, offering high rigidity and fast response times, which are beneficial for heavy-duty tasks. The dynamics of these joints can be modeled using equations of motion. For instance, the torque $\tau$ required for a joint in a bionic robot can be described by:
$$ \tau = I \alpha + b \omega + mg l \sin(\theta) $$
where $I$ is the moment of inertia, $\alpha$ is the angular acceleration, $b$ is the damping coefficient, $\omega$ is the angular velocity, $m$ is the mass, $g$ is gravity, $l$ is the length, and $\theta$ is the angle. Patent data shows that both serial and parallel structures have seen increasing applications, with parallel structures gaining traction in recent years due to their performance advantages. This suggests that bionic robots will continue to employ a mix of joint designs tailored to specific needs, such as exploration in rugged terrains or precise manipulations in industrial settings.
| Year | Serial Structure | Parallel Structure |
|---|---|---|
| 2010 | 8 | 6 |
| 2011 | 10 | 7 |
| 2012 | 12 | 9 |
| 2013 | 14 | 11 |
| 2014 | 16 | 13 |
| 2015 | 18 | 15 |
| 2016 | 20 | 17 |
| 2017 | 22 | 19 |
| 2018 | 24 | 21 |
| 2019 | 26 | 23 |
| 2020 | 28 | 25 |
| 2021 | 30 | 27 |
| 2022 | 32 | 29 |
| 2023 | 34 | 31 |
| 2024 | 30 | 28 |
An examination of major applicants in the quadruped bionic robot field reveals a competitive landscape dominated by Chinese entities, which account for five of the top six applicants by patent count. These include universities and companies that have made significant strides in electric drive technology, leveraging advantages in cost control and compact design. For example, one Chinese university has developed hydraulic-driven bionic robots capable of high-speed walking and has commercialized small electric models, with patents covering various aspects like parallel leg structures and motion control methods. Similarly, companies in cities like Hangzhou have focused on pure electric drive systems, leading to products that excel in real-world applications such as complex terrain navigation. In contrast, a prominent American firm is known for pioneering hydraulic systems but faces competition from electric-driven bionic robots. This dynamic indicates that Chinese innovators are well-positioned to lead the global market for bionic robots, particularly as electric drive becomes more prevalent.
The dominance of electric drive in patent applications aligns with broader trends in robotics, where efficiency and sustainability are prioritized. Chinese applicants have capitalized on this by investing in high-performance motors and AI chips, which are crucial for enhancing the capabilities of bionic robots. The integration of advanced control algorithms, often based on neural networks, allows these bionic robots to perform complex tasks autonomously. For instance, the control input $u(t)$ in a bionic robot can be optimized using a proportional-integral-derivative (PID) controller:
$$ u(t) = K_p e(t) + K_i \int_0^t e(\tau) d\tau + K_d \frac{de(t)}{dt} $$
where $e(t)$ is the error signal, and $K_p$, $K_i$, and $K_d$ are tuning parameters. Such mathematical models underpin the innovation in bionic robots, enabling precise movement and adaptation. The collaborative efforts between academia and industry in China have fostered a robust ecosystem for bionic robot development, suggesting that future breakthroughs will emerge from these partnerships.
In conclusion, the analysis of patent data for quadruped bionic robots indicates a promising future with continued growth in innovation. We project that global patent applications will rise, driven by advancements in leg technology and control methods. Electric drive systems are expected to dominate due to their efficiency and adaptability, while serial and parallel joint structures will coexist, each serving specific applications in bionic robots. The performance of these bionic robots will heavily rely on improvements in high-load-density motors and high-performance AI chips. The load density $\rho$ and computational power can be linked through performance metrics such as the operational efficiency $\eta$, defined as:
$$ \eta = \frac{\text{Work Output}}{\text{Energy Input}} = \frac{F \cdot d}{P \cdot t} $$
where $F$ is force, $d$ is distance, $P$ is power, and $t$ is time. Enhancements in these areas will enable bionic robots to achieve higher mobility, intelligence, and autonomy, expanding their use in military, industrial, and civilian sectors. Moreover, the underdeveloped tail and spine technologies present opportunities for innovation, potentially leading to more versatile bionic robots. As the field evolves, we anticipate that bionic robots will become integral to various applications, from disaster response to everyday assistance, underscoring the importance of ongoing research and investment in this exciting domain of bionic robots.
Overall, this patent-based analysis provides a comprehensive outlook on quadruped bionic robot technology, highlighting key trends and future directions. By leveraging these insights, stakeholders can make informed decisions to foster innovation and capitalize on emerging opportunities in the development of bionic robots. The continuous evolution of bionic robots promises to transform how we interact with complex environments, making them an indispensable part of the technological landscape.