Collision detection using a flexible link manipulator: a feasibility study

Stochastic Systems Theory and its Applications (SSS)

Yagi

2016

In use of a multi-link flexible manipulator in general environments such as homes and offices, collisions between the flexible manipulator and various obstacles and/or working humans is unpredictable and brings serious damage to the manipulator and humans or obstacles. For example, when the flexible manipulator is used for assistant of the meal, humans or obstacles can be moving in the work space of the flexible manipulator. It causes the collision between the flexible manipulator and the unknown obstacles and there are the cases which cannot be avoided the collision. In order to reduce the damage of the manipulator and the humans and then to re-plan the path plan to the desired position, the unexpected contacts or collisions should quickly be detected and the collided link should be identified for reacting to suspend the motion of the manipulator and for planning new path. This paper presents a method of collision detection for each link of a two-link flexible manipulator by introducing respective collision detection function based on residual processes generated by the innovation process of a nonlinear state estimator. Furthermore, the mathematical structure of collision detection for each link is investigated.

Section: Approximated Structure Of Two-link Flexible Manipulatormentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An Approach of Collision Detection and Link Identification for Two-Link Flexible Manipulators Using Nonlinear State Estimator

Okamoto

Stochastic Systems Theory and its Applications (SSS)

Yagi

2016

“…Several researches on collision detection methods for flexible arms have already been conducted [7]- [11]. Moorehead and Wang proposed a collision detection method for a flexible cantilevered beam by using two strain gauges to determine the intensity and position of the external force resulting from a collision [7].…”

Section: Such Flexible Arms Have Useful Applications Inmentioning

confidence: 99%

“…Moorehead and Wang proposed a collision detection method for a flexible cantilevered beam by using two strain gauges to determine the intensity and position of the external force resulting from a collision [7]. In their approach, estimation of the contact position was achieved by observing the relation between the positions of the strain gauges and bending moments measured by sensors.…”

Section: Such Flexible Arms Have Useful Applications Inmentioning

confidence: 99%

Robust Filter Based Control of A Single-link Flexible Arm and Its Collision Detection Using Innovation Process

Stochastic Systems Theory and its Applications (SSS)

Fujimoto

Moritani

et al. 2012

This paper describes a method of collision detection and control of a single-link flexible arm using a couple of state estimators. In order to improve the control performance of the flexible arm with the innovation based collision detection system when unlooked-for obstacles collide with the side of the arm, we introduce a robust optimal filter, which decouples undesirable effect of the collision force from the estimation error. The controller generates a control torque based on the state estimate using the robust optimal filter. Collision detection is then realized by using the innovation of a Kalman filter. The proposed system enables to avoid that the control performance is deteriorated when collisions occur.

“…They used the deformation of a exible beam for measuring a position of the object. Moorehead and Wang [5] proposed a collision detection method using strain gauges to determine the intensity and position of external force due to collision with a exible cantilevered beam. The estimation of the contact position in their approach was achieved by the mechanical relation between positions of the two strain gauges and the bending moments measured by the sensors.…”

Section: Introductionmentioning

confidence: 99%

Collision detection and suspend control of parallel- structured single-link flexible arms

Kondo

2008 SICE Annual Conference

2008

This paper presents a method of collision detection and suspend control for parallel-structured single-link exible arms. The exact dynamics of parallel-structured single-link exible arm are described by quite complex nonlinear partial and ordinary differential equations. In this paper, such parallel-structured exible arms are approximately modeled by a single-link exible arm consisting of a exible beam with the same boundary conditions as the parallel-structured one. Collision of the parallel-structured exible arm and an undesirable obstacle is detected using the innovation process of Kalman lter based on the measured data of strain sensors pasted on the side of the arm. The proposed controller for the arm has the following two objectives: i) to rotate the exible arm from the initial position to the desired position; ii) to safely suspend the rotation of the arm when the collision is detected.