Modeling and Force Control of Thin Soft McKibben Actuator

Ismail

2019

IJIE

The hydraulic system has been widely applied in heavy industries for many decades. It is majorly used in heavyduty machineries for example, power steering system [1], excavator [2], rough grinding machine [3] and tractor [4]. The fluid power system can withstand sudden overload and stall without damage. Furthermore, a low compression ratio of fluid allows the power to be transmitted almost instantaneously. Last but not least, the power per weight ratio of hydraulic system is better when compared to conventional system [5], [6]. Commercial heavy-duty machinery uses oil in hydraulic system because of the special characteristics of oil. Oil has an excellent performance on heat dissipation and oil also act as lubricant in the power system. Nonetheless, hydraulics system also showed great result when compared with electric system. The torque of an electric motor is proportional to current supplied and it is limited by magnetic saturation while the hydraulic motor is depended by pressure difference provided by pump. The hydraulic system also has a higher or faster response to change in speed or direction than electric system [7].

Section: Control Strategymentioning

confidence: 99%

“…Predictive Functional Control is first developed by Richalet [25]- [27] in 1968. PFC is developed to overcome the high online computation effort of MPC, which can be only applied on long sampling time control system, chemical plant for instance.…”

Section: Control Strategymentioning

confidence: 99%

System Identification and Model Predictive Control using CVXGEN for Electro-Hydraulic Actuator

Liang

Ismail

2019

IJIE

“…Soft actuators are presently gaining popularity in many robots because of the advantages of high power-to-weight ratio, high compliance, flexible structure, strong reliability for human use and low cost for manufacturing the actuators [19]. McKibben actuator can generate high linearity in force [20] with low hysteresis and dead zone at low pressure. Smaller diameter of McKibben actuator had been developed with many different application [21].…”

Section: A Actuator Characteristicsmentioning

confidence: 99%

Long-Legged Hexapod Giacometti Robot Using Thin Soft McKibben Actuator

IEEE Robot. Autom. Lett.

Endo

Kurumaya

et al. 2018

Self Cite

This letter introduces a lightweight hexapod robot, Giacometti robot, made with long and narrow legs following the Alberto Giacometti's sculpture conception. The goal is achieved by, first, using multiple links with thin and soft McKibben actuators, and second, choosing a leg design which is narrow in comparison to its body's length and height, unlike conventional robot design. By such design characteristic, the leg will exhibit elastic deformations due to the low stiffness property of the thin link structure. Then, we model the leg structure and conduct the deflection analysis to confirm the capability of the leg to perform walking motion. The high force to weight ratio characteristics of the actuator provided the ability to drive the system, as shown by a static model and further validated experimentally. To compensate for the high elastic structural flexibility of the legs, two walking gaits namely customized Wave gait and Giacometti gait were introduced. The robot could walk successfully with both gaits at maximum speed of 0.005 and 0.05 m/s, respectively. It is envisaged that the lightweight Giacometti robot design can be very useful in legged robotic exploration.

“…These dimensions were adjusted to the artificial neck by measuring the distances between the insertion points of the different muscles on the artificial structure combining bones and ligaments for the configurations of interest. The performance of the multifilament PAMs [15], [18] resembles that of human muscle [19], [20] in terms of force and contraction, providing a slightly higher force for an equivalent cross sectional area and a somewhat lower contraction. Thus, by mimicking the dimensions of the human muscles, the performance obtained from the artificial muscles in the artificial neck is similar to that of the biological muscles in the human neck.…”

Section: Musclesmentioning

confidence: 99%

Multifilament pneumatic artificial muscles to mimic the human neck

Garriga-Casanovas

2017 IEEE International Conference on Robotics and Biomimetics (ROBIO)

Hiramitsu

et al. 2017

Self Cite

Pneumatic Artificial Muscles (PAMs) are actuators that resemble human muscles, and offer an attractive performance in various aspects including robustness, simplicity, high specific power and high force for a given volume. These characteristics render them good candidates for use in humanoid robots. The use of traditional PAMs to closely mimic human structures, however, is difficult due to their relatively large size and relatively fixed designs. The recent development of multifilament PAMs enables the realization of humanoid robots that more closely mimic the human anatomy. In this paper, the application of multifilament PAMs to mimic the human neck is presented. First, the main structures of the human neck anatomy in terms of bones, ligaments and muscles are identified and detailed. The design to mimic each of these structures is subsequently described, together with the most relevant parts of the manufacturing process. The integrated neck is then presented, and the method to actuate it is outlined. The results of motion of the artificial neck when actuating different groups of muscles that mimic those in the human anatomy are reported, confirming a motion that is equivalent to that of the human neck. The results also indicate a range of motion of the robot neck somewhat lower than that of its human counterpart, and the reasons for this are discussed. Finally, future directions for improved motion range, stability, durability and efficiency are outlined.