The passive compliance plays a crucial role in steady and secure locomotion of the legged mammal. This paper aims to introduce the elastic element into the traditional high rigid leg structure to mimic the passive compliance capacity of the animal’s leg joint. For this purpose, based on the analysis of physiological structure of dog leg, the principle of passive compliance leg is proposed firstly. Further more, the single-edge dual-piston pneumatic prop characterizing by small size, large stiffness and high integration is designed and used to connect the thigh component in series with the calf by means of the added anti-torque arm. Finally, the effectiveness of the new structure is validated through the experiments on the single leg physical platform as well as the results from simulations. All results show that with the help of this passive compliance the impact force between the ground and robot feet can be effectively buffered no matter the actuator with poor responsiveness. In the meantime the motion stability and foot trajectory tracking accuracy are also effectively improved in both position control and force control.
GuWCaiSHuY, et al. Trajectory planning and tracking control of a ground mobile robot: a reconstruction approach towards space vehicle. ISA Trans2019; 87: 116–128.
2.
BruzzoneLBaggettaMNodehiSE, et al. Functional design of a hybrid leg-wheel-track ground mobile robot. Machines2021; 9(1): 10.
3.
RaibertMH.Legged robots that balance. MIT Press, London, England, 1986.
4.
SunTXiangXSuW, et al. A transformable wheel-legged mobile robot: design, analysis and experiment. Robot Auton Syst2017; 98: 30–41.
5.
JamesPMPrakashAKalburgiV, et al. Design, analysis, manufacturing of four-legged walking robot with insect type leg. Mater Today Proc2021; 46: 4647–4652.
6.
PanSShiLGuoS. A kinect-based real-time compressive tracking prototype system for amphibious spherical robots. Sensors2015; 15(4): 8232–8252.
7.
BaKYuBGaoZ, et al. Parameters sensitivity analysis of position-based impedance control for bionic legged robots’ HDU. Appl Sci2017; 7(10): 1035.
8.
HoganN. Impedance control: an approach to manipulation. In: 1984 American control conference, 1984, pp.304–313. New York: IEEE.
9.
VijayASParthNDoollaS, et al. An adaptive virtual impedance control for improving power sharing among inverters in islanded ac microgrids. IEEE Transactions on Smart Grid2020; 12(4): 2991–3003.
10.
KhatibO. A unified approach for motion and force control of robot manipulators: the operational space formulation. IEEE J Robot Autom1987; 3(1): 43–53.
11.
JerryPDilworthPPrattG. Virtual model control of a bipedal walking robot. In: Proceedings of international conference on robotics and automation, 1997, vol. 1, pp.193–198. New York: IEEE.
12.
SunYUbellackerWLMaWL, et al. Online learning of unknown dynamics for model-based controllers in legged locomotion. IEEE Robot Autom Lett2021; 6(4): 8442–8449.
13.
KuindersmaSPermenterFTedrakeR. An efficiently solvable quadratic program for stabilizing dynamic locomotion. In: 2014 IEEE international conference on robotics and automation (ICRA), 2014, pp.2589–2594. New York: IEEE.
14.
LeeYHwangSParkJ. Balancing of humanoid robot using contact force/moment control by task-oriented whole body control framework. Auton Robots2016; 40(3): 457–472.
15.
ElmorshedyMFXuWEl-SousyFFM, et al. Recent achievements in model predictive control techniques for industrial motor: a comprehensive state-of-the-art. IEEE Access2021; 9: 58170–58191.
16.
HuJShanYGuerreroJM, et al. Model predictive control of microgrids – an overview. Renew Sustain Energ Rev2021; 136: 110422.
17.
HutterMGehringCLauberA, et al. Anymal-toward legged robots for harsh environments. Advanced Robotics2017; 31(17): 918–931.
18.
BledtGPowellMJKatzB, et al. MIT cheetah 3: design and control of a robust, dynamic quadruped robot. In: 2018 IEEE/RSJ international conference on intelligent robots and systems (IROS), 2018, pp.2245–2252. New York: IEEE.
19.
WiedebachGBertrandSWuT, et al. Walking on partial footholds including line contacts with the humanoid robot atlas. In: 2016 IEEE-RAS 16th international conference on humanoid robots (humanoids), 2016, pp.1312–1319. New York: IEEE.
20.
UrbainGBarasuolVSeminiC, et al. Effect of compliance on morphological control of dynamic locomotion with hyq. Auton Robots2021; 45(3): 421–434.
21.
TripathySGaurS. Rough terrain quadruped robot- BigDog. Mater Today Proc2021. (in press)
22.
BiswalPMohantyPK. Development of quadruped walking robots: a review. Ain Shams Eng J2021; 12(2): 2017–2031.
23.
SharbafiMAYazdanpanahMJAhmadabadiMN, et al. Parallel compliance design for increasing robustness and efficiency in legged locomotion–theoretical background and applications. IEEE/ASME Trans Mechatron2020; 26(1): 335–346.
24.
MeiBXieFLiuXJ, et al. Elasto-geometrical error modeling and compensation of a five-axis parallel machining robot. Precis Eng2021; 69: 48–61.
25.
PeatDFikfakVvan der ZeeE. Behavioural compliance theory. J Int Dispute Settlement2022; 13(2): 167–178.
26.
ChenJLiangZZhuY, et al. Towards the exploitation of physical compliance in segmented and electrically actuated robotic legs: A review focused on elastic mechanisms. Sensors2019; 19(24): 5351.
27.
BarasuolVVillarreal-MagañaOASangiahD, et al. Highly-integrated hydraulic smart actuators and smart manifolds for high-bandwidth force control. Front Rob AI2018; 5: 51.
28.
GuptaA. Real-world clinical effectiveness and tolerability of hydroxychloroquine 400 mg in uncontrolled type 2 diabetes subjects who are not willing to initiate insulin therapy (hyq-real-world study). Curr Diabetes Rev2019; 15(6): 510–519.
29.
HuaZRongXLiY, et al. Design, modelling and validation of hydraulic servo actuator with passive compliance for legged robots. IEEE Access2018; 6: 59486–59495.
30.
PouyaSKhodabakhshMSpröwitzA, et al. Spinal joint compliance and actuation in a simulated bounding quadruped robot. Auton Robots2017; 41(2): 437–452.
31.
KhoramshahiMSpröwitzATuleuA, et al. Benefits of an active spine supported bounding locomotion with a small compliant quadruped robot. In: 2013 IEEE international conference on robotics and automation, 2013, pp.3329–3334. New York: IEEE.
32.
HuangWXiaoJZengF, et al. A quadruped robot with three-dimensional flexible legs. Sensors2021; 21(14): 4907.
33.
ThrallDEDacvrDVMRobertsonID, et al. Atlas of normal radiographic anatomy and anatomic variants in the dog and cat. Elsevier Health Sciences, Louis, Missouri.
34.
NiikuraANabaeHEndoG, et al. Giraffe neck robot: First step toward a powerful and flexible robot prototyping based on giraffe anatomy. IEEE Robot Autom Lett2022; 7(2): 3539–3546.
35.
NiuGShangFKrishnamurthyM, et al. Evaluation and selection of accumulator size in electric-hydraulic hybrid (eh2) powertrain. In: 2016 IEEE transportation electrification conference and expo (ITEC), 2016, pp.1–6. New York: IEEE.
36.
NguyenMHDaoHVAhnKK. Active disturbance rejection control for position tracking of electro-hydraulic servo systems under modeling uncertainty and external load. Actuators2021; 10: 20.
37.
LynnAEdzkoSEshraghiM, et al. Modeling hydraulic regenerative hybrid vehicles using AMESim and Matlab/Simulink. In: Enabling technologies for simulation science IX, 2005, vol. 5805, pp.24–40. Bellingham, Washington: SPIE.
38.
ZhangGJiangZLiY, et al. Active compliance control of the hydraulic actuated leg prototype. Assem Autom2017; 37: 356–368.
