First Test Results of a Haptic Tele-Operation System to Enhance Stability of Telescopic Handlers

Author(s):  
Stefano Cenci ◽  
Giulio Rosati ◽  
Damiano Zanotto ◽  
Fabio Oscari ◽  
Aldo Rossi

According to a recent report of ILO (International Labour Organization), more than two million people die or loose the working capability every year because of accidents or work-related diseases. A large portion of these accidents are related to the execution of motion and transportation tasks involving heavy duty machines. The insufficient degree of interaction between the human operator and the machine may be regarded as one of the major causes of this phenomenon. The main goal of the tele-operation system presented in this paper is to both preserving slave (machine) stability, by reducing the inputs of slave actuators when certain unsafe working conditions occur, and improving the level of interaction at master (operator) side. Different control schemes are proposed in the paper, including several combinations of master and slave control strategies. The effectiveness of the algorithms is analyzed by presenting some experimental results, based on the use of a two degrees-of-freedom force feedback input device (with one active actuator and one passive stiff joint) coupled with a simulator of a telescopic handler.

Author(s):  
Huzefa Shakir ◽  
Won-Jong Kim

In this paper, we consider the problem of designing a multiscale control for plants with conflicting time-domain performance requirements. These results follow from the conventional optimal proportional-integral (PI) control. Four different design methods are proposed: (1) a controller-switch technique which makes use of employing two different controllers designed to meet two different performances and are switched during the course of operation, (2) an integral-reset scheme, which resets the integral term in the control law when the new reference point is reached, (3) controller-switch and integral-reset schemes put together to take benefits of both of them, (4) a model-following approach that uses a dynamic reference model without increasing the overall dimension of the system. The objective of the last scheme is to make the output of the plant track the output of the model as closely as possible. Stability analyses and a comparison between the performances of these methods are given. All these methods give better performances as compared with conventional control schemes. Block diagrams are given and step responses are obtained to demonstrate the proposed methods. A six degrees-of-freedom (DOFs) magnetically levitated (maglev) stage with a second-order pure-mass model has been used to demonstrate the capabilities of the aforementioned control strategies. These strategies are not plant-specific and may be generalized to any higher-order plant.


Author(s):  
Won-jong Kim ◽  
Himanshu Maheshwari ◽  
Jie Gu

Manufacture of nanoscale structures and atomic-level manipulation is an emerging technology field in the 21st century [1,2]. This paper presents a novel magnetically levitated instrument capable of six-degrees-of-freedom (6-DOF) motion with a single moving part. The applications, where this generic positioning device can be used, are manufacturing of nanoscale structures, assembly and packaging of microparts, vibration isolation for delicate instrumentation and motion/force feedback in telepresence surgery. The key element of this stage is a linear actuator capable of providing forces in both suspension and translation without contact. The total range of motion for the linear actuator is ±250 μm. In this paper, we present the closed-loop control test results and stochastic noise/disturbance analysis and prediction for the linear actuator.


2012 ◽  
Vol 24 (6) ◽  
pp. 958-966 ◽  
Author(s):  
Lingtao Huang ◽  
◽  
Takuya Kawamura ◽  
Hironao Yamada ◽  

We developed a master-slave operation system for a teleoperation construction robot that recognizes the hardness of a grasped object. To manipulate an object, the system uses an excavator with four degrees of freedom as a slave and two joysticks with force feedback equipment as a master. Based on creating a friendly user interface, the operation system uses multimodel sensory force and visual feedback to successfully discriminate among soft object types during operation. The construction robot measures the hardness of an object using the pressure of a piston obtained by pressure sensors on the cylinder and the closed or open state of a fork glove in the process of grasping an object. By incorporating an object-hardness calculation method with master-slave control of the system, an operator then can feel the sense of reaction force to joysticks and distinguish the hardness of an object while controlling the construction robot. In addition, parameters on object-hardness calculation are presented to the operator to improve the system’s controllability. Color prompting is provided in virtual space to enable the operator to identify the hardness of an object. To evaluate the system, object-type recognition tests were conducted, including the grasping and conveying of blocks of concrete, tires, urethane foam and sponge foam. According to statistical analysis of experimental results, we confirmed that the operation system contributes to achieving the successful discrimination of object hardness during teleoperation work.


2010 ◽  
Vol 2 (2) ◽  
pp. 8
Author(s):  
Evy Setiawati

Rattan on frequently attacked by the powder post beetle (Tellu, 2001). The prevention of dry powder attacks is done by preservation. The increasing resistant of rattan from insect attack can be done by an environmentally friendly preservative, the Galam wood vinegar. This research  aims to determine the most effective concentration of preservative that shows the lowest attacks level of D. Farb minutus powder. The rattan used is green rattan (Calamus sp.) The concentration of preservative that are used:10%, 40%, 70% and 100%. The testing of dry powder attack  used force feedback method. The effectiveness test parameters of wood vinegar to dry powder attacks  included degree of protection Dinoderus minutus Farb. powder,  reduction percentage of rattan weight and the mortality of dry powder Dinoderus sp for toxicological testing of wood vinegar. The test results showed that the degree of protection powder in rattan growing along with the increased concentration of preservatives. The higher the concentration of  wood vinegar, the smaller the reduction of rattan weight and the higher the mortality rate of dry powder. Keywords: resistant of rattan, wood vinegar, Dinoderus minutus.


Robotica ◽  
2021 ◽  
pp. 1-13
Author(s):  
Sibyla Andreuchetti ◽  
Vinícius M. Oliveira ◽  
Toshio Fukuda

SUMMARY Many different control schemes have been proposed in the technical literature to control the special class of underactuated systems, the- so-called brachiation robots. However, most of these schemes are limited with regard to the method by which the robot executes the brachiation movement. Moreover, many of these control strategies do not take into account the energy of the system as a decision variable. To observe the behavior of the system’s, energy is very important for a better understanding of the robot dynamics while performing the motion. This paper discusses a variety of energy-based strategies to better understand how the system’s energy may influence the type of motion (under-swing or overhand) the robot should perform.


Author(s):  
Xiaoli Zhang ◽  
Carl A. Nelson

The size and limited dexterity of current surgical robotic systems are factors which limit their usefulness. To improve the level of assimilation of surgical robots in minimally invasive surgery (MIS), a compact, lightweight surgical robotic positioning mechanism with four degrees of freedom (DOF) (three rotational DOF and one translation DOF) is proposed in this paper. This spatial mechanism based on a bevel-gear wrist is remotely driven with three rotation axes intersecting at a remote rotation center (the MIS entry port). Forward and inverse kinematics are derived, and these are used for optimizing the mechanism structure given workspace requirements. By evaluating different spherical geared configurations with various link angles and pitch angles, an optimal design is achieved which performs surgical tool positioning throughout the desired kinematic workspace while occupying a small space bounded by a hemisphere of radius 13.7 cm. This optimized workspace conservatively accounts for collision avoidance between patient and robot or internally between the robot links. This resultant mechanism is highly compact and yet has the dexterity to cover the extended workspace typically required in telesurgery. It can also be used for tool tracking and skills assessment. Due to the linear nature of the gearing relationships, it may also be well suited for implementing force feedback for telesurgery.


Author(s):  
Alireza Marzbanrad ◽  
Jalil Sharafi ◽  
Mohammad Eghtesad ◽  
Reza Kamali

This is report of design, construction and control of “Ariana-I”, an Underwater Remotely Operated Vehicle (ROV), built in Shiraz University Robotic Lab. This ROV is equipped with roll, pitch, heading, and depth sensors which provide sufficient feedback signals to give the system six degrees-of-freedom actuation. Although its center of gravity and center of buoyancy are positioned in such a way that Ariana-I ROV is self-stabilized, but the combinations of sensors and speed controlled drivers provide more stability of the system without the operator involvement. Video vision is provided for the system with Ethernet link to the operation unit. Control commands and sensor feedbacks are transferred on RS485 bus; video signal, water leakage alarm, and battery charging wires are provided on the same multi-core cable. While simple PI controllers would improve the pitch and roll stability of the system, various control schemes can be applied for heading to track different paths. The net weight of ROV out of water is about 130kg with frame dimensions of 130×100×65cm. Ariana-I ROV is designed such that it is possible to be equipped with different tools such as mechanical arms, thanks to microprocessor based control system provided with two directional high speed communication cables for on line vision and operation unit.


2015 ◽  
Vol 2015 ◽  
pp. 1-13
Author(s):  
Yang Liu ◽  
Shuhan Wang ◽  
Peng Dong ◽  
Xiangyang Xu

An electric oil pump (EOP) was integrated into the hydraulic system and an automatic transmission (AT) mechanical oil pump (MOP) was downsized. These processes were performed to combine a start-stop function with the AT and further improve the transmission efficiency. Furthermore, this study established a dynamics model of power loss and leakage of an 8-speed AT; a flow-based control algorithm of the EOP was then developed to realize the start-stop function and support the MOP to meet the flow requirement of the system. Based on a driving simulation method, sizes of the MOP and EOP that ensured optimal fuel economy were selected. A control strategy for the starting clutch was also developed to minimize the starting delay of the test vehicle. A test environment on a rig and prototype vehicle was established to verify the feasibility of the proposed control strategies. The test results indicated that the transmission functioned favorably with the novel two-pump system presented, and a quick and smooth starting performance was achieved when the engine was restarted. The findings in this study are extremely valuable for forward designs of an AT for realizing start-stop function and improving efficiency.


2021 ◽  
pp. 1-63
Author(s):  
Jin Lixing ◽  
Duan Xingguang ◽  
Li Changsheng ◽  
Shi Qingxin ◽  
Wen Hao ◽  
...  

Abstract This paper presents a novel parallel architecture with seven active degrees of freedom (DOFs) for general-purpose haptic devices. The prime features of the proposed mechanism are partial decoupling, large dexterous working area, and fixed actuators. The detailed processes of design, modeling, and optimization are introduced and the performance is simulated. After that, a mechanical prototype is fabricated and tested. Results of the simulations and experiments reveal that the proposed mechanism possesses excellent performances on motion flexibility and force feedback. This paper aims to provide a remarkable solution of the general-purpose haptic device for teleoperation systems with uncertain mission in complex applications.


2021 ◽  
Vol 9 (2) ◽  
pp. 142-150
Author(s):  
Ivan Guschin ◽  
Anton Leschinskiy ◽  
Andrey Zhukov ◽  
Alexander Zarukin ◽  
Vyacheslav Kiryukhin ◽  
...  

The results of the development of a radiation-tolerant robotic complex URS-2 for operation in hot cells at nuclear enterprises are presented. The robotic complex consists of several original components: robotic arm, control device with force feedback, control panel with hardware buttons and touch screen, control computer with system and application software, control-and-power cabinet. The robotic manipulator has 6 degrees of freedom, replaceable pneumatic grippers and is characterized by high radiation tolerance, similar to that of mechanical master-slave manipulators. The original design of the control device based on the delta-robot model that implements a copying mode of manual control of the robotic complex with force feedback is presented. The hardware and software solutions developed has made it possible to create a virtual simulator of the RTC for testing innovative methods of remote control of the robot, as well as teaching operators to perform technological tasks in hot cells. The experimental model of the robotic complex has demonstrated the ability to perform basic technological tasks in a demo hot cell, both in manual and automatic modes.


Sign in / Sign up

Export Citation Format

Share Document