We present a novel application of continuum robots
acting as concrete hoses to support 3D printing of cementitious
materials. An industrial concrete hose was fitted with a cable
harness and remotely actuated via tendons. The resulting
continuum hose robot exhibited non constant curvature. In
order to account for this, a new geometric approach to modeling
variable curvature inverse kinematics using Euler curves is
introduced herein. The new closed form model does not impose
any additional computational cost compared to the constant
curvature model and results in a marked improvement in the
observed performance. Experiments involving 3D printing with
cementitious mortar using a continuum hose robot were also
conducted.
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Modeling Variable Curvature Parallel Continuum Robots Using Euler Curves
In this paper, we propose and investigate a new approach to modeling variable curvature continuum robot sections, based on Euler spirals. Euler spirals, also termed Clothoids, or Cornu spirals, are those curves in which the curvature increases linearly with their arc length. In this work, Euler spirals are applied to the kinematic modeling of continuum robots for the first time. The approach was evaluated using the sections of numerous continuum robots, including two novel parallel continuum robots. Each robot consists of three parallel sections, each with three thin, long McKibben actuators. These sections are poorly modeled by the widely used constant curvature kinematic model. The constant curvature and Euler spiral models were compared and the Euler spiral method was seen to be a significantly better match for a wide range of configurations of the robot hardware.
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- Award ID(s):
- 1718755
- PAR ID:
- 10110833
- Date Published:
- Journal Name:
- 2019 International Conference on Robotics and Automation (ICRA)
- Page Range / eLocation ID:
- 1679 to 1685
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICRA.2019.8794238
