Font Size: a A A

Artificial Muscle And Joint Design For Humanoid Robots

Posted on:2009-10-09Degree:DoctorType:Dissertation
Country:ChinaCandidate:J T ZhangFull Text:PDF
GTID:1118360242495830Subject:Pattern Recognition and Intelligent Systems
Abstract/Summary:PDF Full Text Request
Recently, humanoid robot has become the focus of robot research. Humanoid robot imposed rigorous requests on mechanic and drivers. The designs of joint and its driver are the key problems. Traditional drivers for robot's joint include fluid drive, pneumatic drive, and electromagnetic motor, etc, but there are many limits when they are applied on humanoid robots. This paper has proposed a new drive structure for humanoid robots. The drive structure includes artificial muscle and artificial joint which has large torque. The muscle and the joint were designed independently while cooperated with each other. The artificial joint was not as the rotary part as in traditional robot but worked for supporting and maintaining the gesture. The drivers of limb and end operator were fulfilled by the artificial muscle.In order to satisfy the requests of large force/velocity output and high precision of robots' actuator, this research mainly concludes the following studies.The basic working characteristics of piezoelectric pile were summarized and induced. The essential differences between piezoelectric ultrasonic motor and inchworm actuators were analyzed. The motion trajectories of the end of clamping structure were exploited, and the effects of the motion trajectories to friction were compared. The basic principle of inchworm, which was applied in artificial muscle, was concluded and a new model of inchworm motion, which was applied in artificial joint, was proposed.A new artificial muscle was proposed based on basic inchworm motion and converse piezoelectric effects. The actuator designed has unique flexible hinge and can adjust the center of anchoring/loosening. The principle, mechanical realization, and finite element analysis for the major parts were introduced. The actuator can work at high frequency and possess high speed, large travel, and high load. It also has high operation stability and practical value.In order to get and optimize the performance of the actuator, the kinetics models were founded for the clamping system, the driving system, and friction system, etc. Three friction models, including classical (coulomb) friction model, the karnopp model, and the reset integrator model, were compared. As the reset integrator modal is the most precise model, it was applied in the friction system model. The simulation was processed and the relationships between the velocity and load, the signal's frequency, and work style, were also analyzed. As an actuator, the artificial muscle has favorable performance.Another artificial muscle and a new artificial joint were designed. The principle, mechanical realization was introduced. This artificial muscle had different mechanic structure but the same driving principle with the muscle introduced in the front of this paper. The new artificial joint was designed based on the new model of inchworm motion. According to the research, the joint has large torque and self-locking characteristic.As a result, the performance of the artificial muscle and joint which were designed in this paper could satisfy the humanoid robot well. It established the foundation for the further humanoid driver research.
Keywords/Search Tags:humanoid robot, artificial muscle, artificial joint, inchworm actuator, flexible hinge, simulation
PDF Full Text Request
Related items