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Article
Publication date: 1 July 2006

L.R. Palmer and D.E. Orin

Legged vehicles offer several advantages over wheeled vehicles, particularly on broken terrain, but are presently too slow to be considered for many high‐speed tasks. This paper…

608

Abstract

Purpose

Legged vehicles offer several advantages over wheeled vehicles, particularly on broken terrain, but are presently too slow to be considered for many high‐speed tasks. This paper presents an effective 3D controller for a high‐speed quadruped trot.

Design/methodology/approach

To successfully regulate forward velocity and heading, secondary motions such as body pitch and roll must be stabilised. The complicated coupling between pitch and roll motion causes the control effort on one axis to disturb the motion and control effort of the other. Unlike the modular methods in previous research, the algorithm presented here employs a cooperative approach where pitch stability effort is directly accounted for by the roll controller.

Findings

When the secondary motions such as pitch and roll are well stabilized, forward velocity and heading can be regulated up to 3 m/s and 20°/s, respectively.

Research limitations/implications

For many quadrupeds, trotting is usually employed as the precursor to galloping, which is ultimately used at top speeds. Because these two gaits are commonly used together, we expect their control algorithms to share a number of similar components. It is then expected that understanding the quadruped trot will serve as a valuable foundation to understanding the quadruped gallop.

Originality/value

This appears to be the first reported regulation of quadruped heading while running at significant speeds.

Details

Industrial Robot: An International Journal, vol. 33 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 2 April 2019

Tayfun Abut and Servet Soyguder

This paper aims to keep the pendulum on the linear moving car vertically balanced and to bring the car to the equilibrium position with the designed controllers.

1347

Abstract

Purpose

This paper aims to keep the pendulum on the linear moving car vertically balanced and to bring the car to the equilibrium position with the designed controllers.

Design/methodology/approach

As inverted pendulum systems are structurally unstable and nonlinear dynamic systems, they are important mechanisms used in engineering and technological developments to apply control techniques on these systems and to develop control algorithms, thus ensuring that the controllers designed for real-time balancing of these systems have certain performance criteria and the selection of each controller method according to performance criteria in the presence of destructive effects is very helpful in getting information about applying the methods to other systems.

Findings

As a result, the designed controllers are implemented on a real-time and real system, and the performance results of the system are obtained graphically, compared and analyzed.

Originality/value

In this study, motion equations of a linear inverted pendulum system are obtained, and classical and artificial intelligence adaptive control algorithms are designed and implemented for real-time control. Classic proportional-integral-derivative (PID) controller, fuzzy logic controller and PID-type Fuzzy adaptive controller methods are used to control the system. Self-tuning PID-type fuzzy adaptive controller was used first in the literature search and success results have been obtained. In this regard, the authors have the idea that this work is an innovative aspect of real-time with self-tuning PID-type fuzzy adaptive controller.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 8 March 2011

Nuria Rosillo, Angel Valera, Francesc Benimeli, Vicente Mata and Francisco Valero

The purpose of this paper is to present the development and validation of a methodology which allows modeling and solving the inverse and direct dynamic problem in real time in…

666

Abstract

Purpose

The purpose of this paper is to present the development and validation of a methodology which allows modeling and solving the inverse and direct dynamic problem in real time in robot manipulators.

Design/methodology/approach

The robot dynamic equation is based on the Gibbs‐Appell equation of motion, yielding a well‐structured set of equations that can be computed in real time. This paper deals with the implementation and calculation of the inverse and direct dynamic problem in robots, with an application to the real‐time control of a PUMA 560 industrial robot provided with an open control architecture based on an industrial personal computer.

Findings

The experimental results show the validity of the dynamic model and that the proposed resolution method for the dynamic problem in real time is suitable for control purposes.

Research limitations/implications

The accuracy of the applied friction model determines the accuracy of the identified overall model and consequently of the control. This is especially obvious in the case of the PUMA 560 robot, in which the presence of friction is remarkable in some of their joints. Hence, future work should focus on identifying a more precise friction model. The robot model could also be extended by incorporating rotor dynamics and could be applied for different robot configurations as parallel robots.

Originality/value

Gibbs‐Appell equations are used in order to develop the robotic manipulator dynamic model, instead of more usual dynamics formulations, due to several advantages that these exhibit. The obtained non‐physical identified parameters are adapted in order to enable their use in a control algorithm.

Details

Industrial Robot: An International Journal, vol. 38 no. 2
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 March 1986

Ronald L. Huston

This paper presents algorithms for computing the angular velocities of the bodies of a multibody system. A multibody system is any collection of connected bodies. The focus is…

85

Abstract

This paper presents algorithms for computing the angular velocities of the bodies of a multibody system. A multibody system is any collection of connected bodies. The focus is upon multibody systems consisting of spherically pinned rigid bodies which do not form closed loops. Simple formulae are presented for computing the angular velocities. It is shown that once the angular velocities are known the entire kinematical description and hence, the dynamics of the system, may be developed routinely and in automated fashion. Extension to more general multibody systems follows without conceptual change in the procedures.

Details

Engineering Computations, vol. 3 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 4 March 2021

Abhishek Kumar Kashyap and Dayal R. Parhi

Humanoid robots have complicated dynamics, and they lack dynamic stability. Despite having similarities in kinematic structure, developing a humanoid robot with robust walking is…

232

Abstract

Purpose

Humanoid robots have complicated dynamics, and they lack dynamic stability. Despite having similarities in kinematic structure, developing a humanoid robot with robust walking is quite difficult. In this paper, an attempt to produce a robust and expected walking gait is made by using an ALO (ant lion optimization) tuned linear inverted pendulum model plus flywheel (LIPM plus flywheel).

Design/methodology/approach

The LIPM plus flywheel provides the stabilized dynamic walking, which is further optimized by ALO during interaction with obstacles. It gives an ultimate turning angle, which makes the robot come closer to the obstacle and provide a turning angle that optimizes the travel length. This enhancement releases the constraint on the height of the COM (center of mass) and provides a larger stride. The framework of a sequential locomotion planer has been discussed to get the expected gait. The proposed method has been successfully tested on a simulated model and validated on the real NAO humanoid robot.

Findings

The convergence curve defends the selection of the proposed controller, and the deviation under 5% between simulation and experimental results in regards to travel length and travel time proves its robustness and efficacy. The trajectory of various joints obtained using the proposed controller is compared with the joint trajectory obtained using the default controller. The comparison shows the stable walking behavior generated by the proposed controller.

Originality/value

Humanoid robots are preferred over mobile robots because they can easily imitate the behaviors of humans and can result in higher output with higher efficiency for repetitive tasks. A controller has been developed using tuning the parameters of LIPM plus flywheel by the ALO approach and implementing it in a humanoid robot. Simulations and experiments have been performed, and joint angles for various joints are calculated and compared with the default controller. The tuned controller can be implemented in various other humanoid robots

Details

International Journal of Intelligent Unmanned Systems, vol. 10 no. 4
Type: Research Article
ISSN: 2049-6427

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Article
Publication date: 15 June 2012

D. Sanz‐Merodio, E. Garcia and P. Gonzalez‐de‐Santos

Reducing energy consumption in walking robots is an issue of great importance in field applications such as humanitarian demining so as to increase mission time for a given power…

436

Abstract

Purpose

Reducing energy consumption in walking robots is an issue of great importance in field applications such as humanitarian demining so as to increase mission time for a given power supply. The purpose of this paper is to address the problem of improving energy efficiency in statically stable walking machines by comparing two leg, insect and mammal, configurations on the hexapod robotic platform SILO6.

Design/methodology/approach

Dynamic simulation of this hexapod is used to develop a set of rules that optimize energy expenditure in both configurations. Later, through a theoretical analysis of energy consumption and experimental measurements in the real platform SILO6, a configuration is chosen.

Findings

It is widely accepted that the mammal configuration in statically stable walking machines is better for supporting high loads, while the insect configuration is considered to be better for improving mobility. However, taking into account the leg dynamics and not only the body weight, different results are obtained. In a mammal configuration, supporting body weight accounts for 5 per cent of power consumption while leg dynamics accounts for 31 per cent.

Originality/value

As this paper demonstrates, the energy expended when the robot walks along a straight and horizontal line is the same for both insect and mammal configurations, while power consumption during crab walking in an insect configuration exceeds power consumption in the mammal configuration.

Details

Industrial Robot: An International Journal, vol. 39 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 April 2004

T.A. Guardabrazo and P. Gonzalez de Santos

An energetic model for walking robots based on both dynamic and actuator models is proposed in this paper. While applied to walking machines, this method allows the evaluation of…

582

Abstract

An energetic model for walking robots based on both dynamic and actuator models is proposed in this paper. While applied to walking machines, this method allows the evaluation of the influence of leg configuration, body weight, and gait parameters on power consumption. The model is validated by using genetic algorithms to identify the unknown parameters, which enables it to be used as a tool to evaluate and optimize the performance of a legged robot configuration according to the power consumption. This method has been applied to find the optimum stride length for the minimum energy expenditure of a biped prototype depending on the speed and payload, considering both level and slope walking.

Details

Industrial Robot: An International Journal, vol. 31 no. 2
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 19 June 2017

Hector Montes, Lisbeth Mena, Roemi Fernández and Manuel Armada

The aim of this paper is to introduce a hexapod walking robot specifically designed for applications in humanitarian demining, intended to operate autonomously for several hours…

282

Abstract

Purpose

The aim of this paper is to introduce a hexapod walking robot specifically designed for applications in humanitarian demining, intended to operate autonomously for several hours. To this end, the paper presents an experimental study for the evaluation of its energy efficiency.

Design/methodology/approach

First, the interest of using a walking robot for detection and localization of anti-personnel landmines is described, followed by the description of the mechanical system and the control architecture of the hexapod robot. Second, the energy efficiency of the hexapod robot is assessed to demonstrate its autonomy for performing humanitarian demining tasks. To achieve this, the power consumed by the robot is measured and logged, with a number of different payloads placed on-board (always including the scanning manipulator arm assembled on the robot front end), during the execution of a discontinuous gait on flat terrain.

Findings

The hexapod walking robot has demonstrated low energy consumption when it is carrying out several locomotion cycles with different loads on it, which is fundamental to have a desired autonomy. It should be considered that the robot has a mass of about 250 kg and that it has been loaded with additional masses of up to 170 kg during the experiments, with a consumption of mean power of 72 W, approximately.

Originality/value

This work provides insight on the use of a walking robot for humanitarian demining tasks, which has high stability and an autonomy of about 3 hours for a robot with high mass and high payload. In addition, the robot can be supervised and controlled remotely, which is an added value when it is working in the field.

Details

Industrial Robot: An International Journal, vol. 44 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 12 March 2018

Harish Kumar Banga, Rajendra M. Belokar, Parveen Kalra and Rajesh Kumar

Ankle–foot orthoses (AFOs) are assistive devices prescribed for a number of physical and neurological disorders affecting the mobility of the lower limbs. Additive manufacturing…

1509

Abstract

Purpose

Ankle–foot orthoses (AFOs) are assistive devices prescribed for a number of physical and neurological disorders affecting the mobility of the lower limbs. Additive manufacturing has been explored as an alternative process; however, it has proved to be inefficient cost-wise. This work aims to explore the possibilities of generating modular AFO elements, namely, calf, shank and footplate, with the localized composite reinforcement that aids in the optimization of the device in terms of functionality, aesthetics, rigidity and cost.

Design/methodology/approach

The conventional lower leg–foot orthosis configuration depends on thermoforming a polymer sheet around a mortar cast with a trademark firmness relying upon the trim-line with the inalienable plan restrictions. In manufacturing of AFO the expert, i.e. orthotist's, guidance is used. Polypropylene and polyethylene material is used in fabrication of AFO to complete all-round reported points of interest over the ordinary outlines, yet their mechanical conduct under administration conditions cannot be effectively anticipated.

Findings

AFOs made of polypropylene and polyethylene material are available in the market, which are used by children of age 3-5 years. With the existing AFO design, patients are facing excessive heating and sweating problems during long-term usage. After feedback from patients and orthotists (who prescribed AFO to patients), an attempt has been made to solve the problem with a new and improved AFO design of AFO by using finite element modelling and stress analysis. Also, the results indicate that the new design is similar to the actual product design.

Originality/value

This work introduces the low-cost 3D printing with reinforcement approach as an alternative route for the designing and manufacturing of orthotic devices with complex shapes. It is expected that new applications add-up to increase the body of knowledge about the behaviour of such products which will mix both areas, composite theory and additive manufacturing. This study investigated the fields related to 3D scanning, 3D printing and computer-aided designing for the manufacturing of a customized AFO.

Details

Rapid Prototyping Journal, vol. 24 no. 2
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 1 February 1989

Gerhard Angermüller, Erich Niedermayr and Norbert Roth

IN a classification of the effects which lead to economic success of industries, the ability to successfully innovate the production processes plays a dominant role. The…

44

Abstract

IN a classification of the effects which lead to economic success of industries, the ability to successfully innovate the production processes plays a dominant role. The competition in the international markets, influenced by overcapacities in the industrial countries and by growing capacities in the countries on the threshold of industrialisation, makes it necessary to be quick in presenting new products on the market while being able to produce these products in the most efficient way. To realise such consumer‐oriented production, two main conditions have to be fulfilled:

Details

Assembly Automation, vol. 9 no. 2
Type: Research Article
ISSN: 0144-5154

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