An efficient motion generation method for redundant humanoid robot arms
based on motion continuity
Meng Li , Weizhong Guo , Rongfu Lin and Changzhen Wu
S chool of Mechanical Engineering, Shanghai Jiaotong Universit y, Shanghai, People’s Republic of China
ABSTR AC T
This paper proposes a novel method of motion generation for redundant humanoid robot arms, which can efficiently generate continuous collision-free arm motion for the preplanned hand trajectory. The proposed method generates the whole arm motion first and then computes the actuators’ motion, which is different from IK (inverse kinematics)-based motion generation methods. Based on the geometric constraints of the preplanned trajectory and the geometric structure of humanoid robot arms, the wrist trajectory and elbow trajectory can be got first without solving inverse kinematics and forward kinematics. Meanwhile, the constraints restrict all feasible arm configurations to an elbow-circle and reduce the arm configuration space to a two-dimension space. By combining the configuration space and collision distribution of arm motion, collision-free arm configurations can be
identified and be used to generate collision-free arm motion, which can avoid unnecessary forward and inverse kinematics. The experiments show that the proposed method can generate continuous and collision-free arm motion for preplanned hand trajectories.
KEY WORDS
K inematic redundanc y ; humanoid robot arms; g e o m e t r i c co n s t rai nt s ; m o t i o n g e n e rat i o n ; o b s t a c l e avoidance
Enhancing older people’s activity and participation with socially assistive robots:
a m u l t i c e n t r e q u a s i - e x p e r i m e n t a l s t u d y u s i n g t h e I C F f r a m e w o r k *
Kazuko Obayashi a, Naonori Kodate b and Shigeru Masuyama c
aSocial Welfare Corporation Tokyo Seishin-kai, Tokyo, Japan; bSchool of Social Policy, Social Work and Social Justice, University College Dublin, Dublin, Ireland; cTravellers Medical Centre, Tokyo Medical University Hospital, Tokyo, Japan
ABSTR AC T
Socially assistive robots (SARs) are seen as part of a pragmatic solution to addressing the increasing demands, shortage of care workers and to realizing the potential of optimum integrated care. Yet their effectiveness and impact on older people’s care, activities and participation are still unknown. A total of 67 people aged 65 and over participated in a 24-week-long, quasi-experimental study in five residential nursing homes in Japan. The personalized care plan and targets were created based
on the framework of the WHO’s International Classification of Function, Disability and Health (ICF). Three types of socially assistive robots were used. The participants in the robot intervention groups showed greater improvements in their scores for targeted activities and participation than the control group. Statistically significant improvements were observed in communication, self care, and social life. SARs have great potential for improving older people’s quality of life. With further research, the use of these robots by older people could be considered as a serious option in the future. In addition, the ICF framework can be utilized further for measuring the effects of introducing SARs on older people’s quality of life.
KEY WORDS
Nursing care; assistive robotics - robotics in application fields; ageing in place; international classification of functioning; disabilities and health
Trunk motion control during the flight phase while hopping considering angular
momentum of a humanoid
Takuya Otani a, Kenji Hashimotob,c, Takaya Isomichid, Akira Natsuharad, Masanori Sakaguchie,
Yasuo Kawakamif, Hun-ok Limc,g and Atsuo Takanishia ,c
aDepartment of Modern Mechanical Engineering, Waseda University, Tokyo, Japan; bDepartment of Mechanical Engineering Informatics, Meiji University, Tokyo, Japan; cHumanoid Robotics Institute, Waseda University, Tokyo, Japan; dGraduate School of Creative Science and Engineering, Waseda University, Tokyo, Japan; eInstitute of Sport Science, ASICS Corporation, Hyogo, Japan; fFaculty of Sport Sciences, Waseda University, Tokyo, Japan; gFaculty of Engineering, Kanagawa University, Yokohama, Kanagawa, Japan
ABSTR AC T
In previous studies, various stabilizing control methods for humanoids during the stance phase while hopping and running were proposed. Although these methods contribute to stability while hopping and running, it is possibility that the control during the flight phase could also affect the stability. In this study, we investigated whether the control during the flight phase can affect the stability of a humanoid while running. To achieve stable hopping, we developed a control system that accounts for the angular momentum of the whole body during the flight phase. In this system, the angular momentum generated by the motion of the lower body in each time interval is calculated during the flight phase, and the trunk joints are controlled to generate the angular momentum necessary to compensate for the deviation of the waist posture, which is used as the reference point for the motion
coordinate system of the robot. Once the proposed control system was developed and simulated, we found that the hopping duration in the unconstrained state was extended.
Accepted 8 September 2018
KEY WORDS
Humanoid; hopping; angular momentum; upper body
