JabRef references

Paredes F, Burgos PN, Torres-Torriti M and Auat Cheein F (2020), "Payload measurementin robotic mobile loaders", In Automining 2020. Santiago, Chile, December, 2020. , pp. 1-8.

[BibTeX]

BibTeX:

@inproceedings{FabianParedes2020,
  author = {Fabián Paredes and Paola Nazate Burgos and Miguel Torres-Torriti and Fernando Auat Cheein},
  title = {Payload measurementin robotic mobile loaders},
  booktitle = {Automining 2020},
  year = {2020},
  pages = {1--8}
}

Calvo-Sánchez M, Torres-Torriti M and Auat Cheein F (2020), "Payload measurementin robotic mobile loaders", In Automining 2020. Santiago, Chile, December, 2020. , pp. 1-8.

[BibTeX]

BibTeX:

@inproceedings{CalvoSanchez2020,
  author = {Martin Calvo-Sánchez and Miguel Torres-Torriti and Fernando Auat Cheein},
  title = {Payload measurementin robotic mobile loaders},
  booktitle = {Automining 2020},
  year = {2020},
  pages = {1--8}
}

Javier Prado A, Chávez D, Camacho O, Torres-Torriti M and Auat Cheein F (2020), "Adaptive Nonlinear MPC for Efficient Trajectory Tracking Applied to Autonomous Mining Skid-Steer Mobile Robots", In 2020 IEEE ANDESCON., Oct, 2020. , pp. 1-6.

[Abstract] [BibTeX] [DOI]

Abstract: The heterogeneous nature of the navigation surface suggests adaptation capabilities in vehicle motion control to overcome the effects of the wheel-terrain interaction. In such scenario, this paper presents an integral adaptive control framework built upon a Nonlinear Moving Horizon Estimator and a Nonlinear Model Predictive Control scheme, under which the objective is to on-line estimate states and model parameters of a robot motion model while autonomously navigating in off-road terrain conditions. With an adjustable model, the controller is made adaptive against terrain changes while tracking prescribed trajectories. The system is composed by two coupled subsystems to represent the vehicle motion and tire slip dynamics. The combined control-estimation strategy works under the Real-Time Iteration scheme to attain reliable computational activity for high-speed tire dynamics (e.g., slip). Trials in a simulation and real test environment with a compact mini-loader Cat^® 262C, as those found in the mining industry, showed that the approach is able to efficiently estimate states and model parameters without exceeding constraints. The analysis of computational efficiency in various hardware configurations is also provided, exhibiting that the rapid optimization involved in the proposed controller is possible for high-speed dynamics.

BibTeX:

@inproceedings{JavierPrado2020,
  author = {Javier Prado, Alvaro and Chávez, Danilo and Camacho, Oscar and Torres-Torriti, Miguel and Auat Cheein, Fernando},
  title = {Adaptive Nonlinear MPC for Efficient Trajectory Tracking Applied to Autonomous Mining Skid-Steer Mobile Robots},
  booktitle = {2020 IEEE ANDESCON},
  year = {2020},
  pages = {1-6},
  doi = {10.1109/ANDESCON50619.2020.9272162}
}

Calvo Sanchez M, Torres-Torriti M and Cheein FA (2020), "Online Inertial Parameter Estimation for Robotic Loaders", IFAC-PapersOnLine., In Proceedings of the 21^st IFAC World Congress,. Berlin, Germany, July, 2020. Vol. 53(2), pp. 8763-8770.

[Abstract] [BibTeX] [DOI] [URL]

Abstract: Payload estimation is essential to measure productivity, evaluate efficiency in industrial operations and adapting control laws according to the carried weight. One particular problem is to identify how much mass is carried in a mining machine while it is being operated without using strain gauge sensors which require frequent calibration and are prone to failure due to mechanical stress. This paper presents an on-line method to estimate a loader’s payload mass, rotational inertia and viscous friction coefficients employing inertial, torque and speed measurements. The proposed approach introduces a mutual information criterion to select those acceleration and velocity measurements that jointly with the excitation force ensure the identifiability of the parameters. The approach relies on the recursive least-squares algorithm for fast update of the parameters. The proposed strategy is also compared to the implementations based on variants of the least-squares estimator, such as the feasible generalized least squares and the total least squares approach. The approach is tested in simulation and validated in experiments with an industrial semi-autonomous skid-steer loader Cat®262C for different loads. Results show that using the recursive least squares it is possible to estimate the parameters with the same level of accuracy than OLS approach, while not needing a large buffer for estimation. Mass is effectively estimated with an RMS error below 1% the total mass of the machine.

BibTeX:

@inproceedings{Calvo2020,
  author = {Martín Calvo Sanchez and Miguel Torres-Torriti and Fernando Auat Cheein},
  title = {Online Inertial Parameter Estimation for Robotic Loaders},
  booktitle = {Proceedings of the 21^st IFAC World Congress,},
  journal = {IFAC-PapersOnLine},
  year = {2020},
  volume = {53},
  number = {2},
  pages = {8763--8770},
  url = {https://www.sciencedirect.com/science/article/pii/S2405896320317808},
  doi = {10.1016/j.ifacol.2020.12.1373}
}

Guevara Gordillo L, Torres-Torriti M and Auat Cheein F (2019), "Collision-free navigation of N-trailer vehicles with motion constraints", In Proceedings of the IEEE/IFAC 12^th International Workshop on Robot Motion and Control (RoMoCo), 8--10 July 20. Poznan, Poland, July, 2019. , pp. 118-123.

[Abstract] [BibTeX] [DOI]

Abstract: In this work, a collision-free navigation strategy for N-trailer vehicles is proposed. This approach is based on a scalable cascaded control scheme to perform several tasks simultaneously: trajectory tracking control, off-track error reduction, external obstacles avoidance, and inter-vehicle collision avoidance. To validate the proposed strategy, a Generalized N-trailer (GNT) structure with a car-like tractor and 10 trailers is tested in simulation to track an U-shape trajectory in presence of unknown obstacles, similar to the trajectories that agricultural vehicles must perform in real applications. The well-known information about external infrastructure is also considered to reduce unsafe trailers off-track errors in turning scenarios. Moreover, the motion constraints imposed by the car-like tractor physical limitations and the interconnections between trailers are also considered by restricting the control input in order to avoid collision between trailers. The simulation results obtained showed a safe navigation which performed feasible maneuvers without collisions between the vehicles' chain and any trailer or external obstacle.

BibTeX:

@inproceedings{Guevara2019,
  author = {Leonardo Guevara Gordillo and Miguel Torres-Torriti and Fernando Auat Cheein},
  title = {Collision-free navigation of N-trailer vehicles with motion constraints},
  booktitle = {Proceedings of the IEEE/IFAC 12^th International Workshop on Robot Motion and Control (RoMoCo), 8--10 July 20},
  year = {2019},
  pages = {118--123},
  doi = {10.1109/RoMoCo.2019.8787374}
}

Taylor W, Cirasuolo M, Afonso J, Carollo M, Evans C, Flores H, Maiolino R, Paltani S, Vanzi L, Abreu M, Amans J-P, Atkinson D, Barrett J, Beard S, Béchet C, Black M, Boettger D, Brierley S, Buscher D, Cabral A, Cochrane W, Coelho J, Colling M, Conzelmann R, Dalessio F, Dauvin L, Davidson G, Drass H, Dünner R, Fairley A, Fasola G, Ferruzzi D, Fisher M, Flores M, Garilli B, Gaudemard J, Gonzalez O, Guinouard I, Gutierrez P, Hammersley P, Haigron R, Haniff C, Hayati M, Ives D, Iwert O, Laporte P, Lee D, Causi GL, Luco Y, Macleod A, Mainieri V, Maire C, Melse B-T, Nix J, Oliva E, Oliveira A, Origlia L, Parry I, Pedichini F, Piazzesi R, Rees P, Reix F, Rodrigues M, Rojas F, Rota S, Royer F, Santos P, Schnell R, Shen T-C, Sordet M, Strachan J, Sun X, Tait G, Torres-Torriti M, Tozzi A, Tulloch S, Navarro ÁV, Dran LV, Waring C, Watson S, Woodward B and Yang Y (2018), "Rising MOONS: an update on the VLT’s next multi-object spectrograph as it begins to grow", In Ground-based and Airborne Instrumentation for Astronomy VII. Vol. 10702, pp. 421 - 440. SPIE.

[Abstract] [BibTeX] [DOI] [URL]

Abstract: After completion of its final-design review last year, it is full steam ahead for the construction of the MOONS instrument - the next generation multi-object spectrograph for the VLT. This remarkable instrument will combine for the first time: the 8 m collecting power of the VLT, 1000 optical fibres with individual robotic positioners and both medium- and high-resolution spectral coverage acreoss the wavelength range 0.65μm - 1.8 μm. Such a facility will allow a veritable host of Galactic, Extragalactic and Cosmological questions to be addressed. In this paper we will report on the current status of the instrument, details of the early testing of key components and the major milestones towards its delivery to the telescope.

BibTeX:

@inproceedings{Taylor2018,
  author = {William Taylor and Michele Cirasuolo and Jose Afonso and Marcella Carollo and Chris Evans and Hector Flores and Roberto Maiolino and Stephane Paltani and Leonardo Vanzi and Manuel Abreu and Jean-Phillipe Amans and David Atkinson and Joe Barrett and Steven Beard and Celementine Béchet and Martin Black and David Boettger and Saskia Brierley and David Buscher and Alexandre Cabral and William Cochrane and João Coelho and Miriam Colling and Ralf Conzelmann and Francesco Dalessio and Louise Dauvin and George Davidson and Holger Drass and Rolando Dünner and Alasdair Fairley and Giles Fasola and Debora Ferruzzi and Martin Fisher and Mauricio Flores and Bianca Garilli and Julien Gaudemard and Oscar Gonzalez and Isabelle Guinouard and Pablo Gutierrez and Peter Hammersley and Régis Haigron and Chris Haniff and Mahmoud Hayati and Derek Ives and Olaf Iwert and Philippe Laporte and David Lee and Gianluca Li Causi and Yerko Luco and Alastair Macleod and Vincenzo Mainieri and Charles Maire and Basile-Thierry Melse and Johannes Nix and Ernesto Oliva and António Oliveira and Livia Origlia and Ian Parry and Fernando Pedichini and Roberto Piazzesi and Phil Rees and Florent Reix and Myriam Rodrigues and Felipe Rojas and Stefano Rota and Frédéric Royer and Pedro Santos and Robin Schnell and Tzu-Chiang Shen and Michael Sordet and Jonathan Strachan and Xiaowei Sun and Graham Tait and Miguel Torres-Torriti and Andre Tozzi and Simon Tulloch and Álvaro Valenzuela Navarro and Lauren Von Dran and Chris Waring and Stephen Watson and Brian Woodward and Yanbin Yang},
  editor = {Christopher J. Evans and Luc Simard and Hideki Takami},
  title = {Rising MOONS: an update on the VLT’s next multi-object spectrograph as it begins to grow},
  booktitle = {Ground-based and Airborne Instrumentation for Astronomy VII},
  publisher = {SPIE},
  year = {2018},
  volume = {10702},
  pages = {421 -- 440},
  url = {https://doi.org/10.1117/12.2313403},
  doi = {10.1117/12.2313403}
}

Rigotti-Thompson M, Torres-Torriti M, Cheein FA and Troni G (2018), "Ground Disturbance Rejection Approach for Mobile Robotic Manipulators with Hydraulic Actuators", In Proceedings of the 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 1--5 October 2018. Madrid, Spain, Oct, 2018. , pp. 5980-5986.

[Abstract] [BibTeX] [DOI]

Abstract: Reducing material spillage by robotic mining mobile manipulators, such as front-end loaders, is necessary to improve mining operations. To this end, the present work proposes an approach to reduce disturbances on the end-effector induced by the terrain and propagated through the wheels and arm links of the machine. The proposed approach is based on an H_∞ control strategy that includes a feedforward action, computed using the pitch rate of the mobile base, and considers the hydraulic arm dynamics, as well as the reaction forces in the contact points of the mobile base, which is modeled as a floating body with non-permanent ground contacts. Alternative control schemes based on the classic proportional-derivative (PD) control, and the Active Disturbance Rejection Control (ADRC), with and without feedforward action, were also implemented and experimentally evaluated using a semiautonomous Cat^® 262C compact skid-steer loader equipped with inclination and inertial sensors. The proposed method reduces disturbances by at least 70% when climbing ramps at 25% of the machine's maximum speed, and by at least 20% when driving over speed bumps which produce disturbances similar to that caused by stones. The proposed disturbance attenuation strategy should help reducing the spillage of material when driving over mounds, inclines or spilled rocks, especially considering that even if existing autonomous machines are able to drive with little operator supervision along mining galleries, they are often unable to avoid disturbing material on the ground or the characteristic unevenness of mining terrains.

BibTeX:

@inproceedings{RigottiThompson2018b,
  author = {Mattia Rigotti-Thompson and Miguel Torres-Torriti and Fernando Auat Cheein and Giancarlo Troni},
  title = {Ground Disturbance Rejection Approach for Mobile Robotic Manipulators with Hydraulic Actuators},
  booktitle = {Proceedings of the 2018 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 1--5 October 2018},
  year = {2018},
  pages = {5980-5986},
  doi = {10.1109/IROS.2018.8594172}
}

Rigotti-Thompson M, Torres-Torriti M, Cheein FA and Troni G (2018), "ℋ_∞ Controller Design for a Robotic Research and Educational Mining Loader", In Proceedings of the 2018 IEEE 19^th International Conference on Research and Education in Mechatronics (REM2018). Delft, Netherlands, June, 2018. , pp. 18-23.

[Abstract] [BibTeX] [DOI]

Abstract: A robotic platform consisting of a skid-steer compact loader is employed as a setup to design and study strategies for reducing material spillage by robotic mining mobile manipulators. The present work describes the design methodology for a controller approach to reduce disturbances on the end-effector induced by the terrain and propagated through the wheels and arm links of the machine. The proposed approach H_∞ control strategy that includes a feedforward action, computed using the pitch rate of the mobile base, and considers the hydraulic arm dynamics, as well as the reaction forces in the contact points of the mobile base. Alternative control schemes based on the classic proportional-derivative (PD) H_∞ strategy without feedforward action, were also implemented and evaluated on simulations and experiments using a semi-autonomous Cat^® 262C compact skid-steer loader equipped with inclination and inertial sensors. The best results were obtained using the proposed approach. The control scheme proposed reduces ground disturbances around 89% and 68% when traversing a 4 m long ramp at 12.5% and 25% of maximum vehicle speed, respectively.

BibTeX:

@inproceedings{RigottiThompson2018,
  author = {Rigotti-Thompson, Mattia and Torres-Torriti, Miguel and Cheein, Fernando Auat and Troni, Giancarlo},
  title = {ℋ_∞ Controller Design for a Robotic Research and Educational Mining Loader},
  booktitle = {Proceedings of the 2018 IEEE 19^th International Conference on Research and Education in Mechatronics (REM2018)},
  year = {2018},
  pages = {18--23},
  doi = {10.1109/REM.2018.8421769}
}

Rigotti-Thompson M, Torres-Torriti M, Cheein FA and Troni G (2018), "Active Rejection ofGround Disturbances for Efficient Payload Haul by Mining Loaders", In Proceedings of the 6^th International Congress on Automation in Mining (Automining2018). Santiago, Chile, June, 2018.

[BibTeX]

BibTeX:

@inproceedings{RigottiThompson2018a,
  author = {Mattia Rigotti-Thompson and Miguel Torres-Torriti and Fernando Auat Cheein and Giancarlo Troni},
  title = {Active Rejection ofGround Disturbances for Efficient Payload Haul by Mining Loaders},
  booktitle = {Proceedings of the 6^th International Congress on Automation in Mining (Automining2018)},
  year = {2018}
}

Drass H, Vanzi L, Torres-Torriti M, Dünner R, Shen T-C, Belmar F, Dauvin L, Staig T, Antognini J, Flores M, Luco Y, Béchet C, Boettger D, Beard S, Montgomery D, Watson S, Cabral A, Hayati M, Abreu M, Phil Rees II, Cirasuolo M, Taylor W and Fairley A (2016), "Implementation and performance of the metrology system for the multi-object optical and near-infrared spectrograph MOONS", In Ground-based and Airborne Instrumentation for Astronomy VI. Vol. 9908, pp. 2498 - 2507. SPIE.

[Abstract] [BibTeX] [DOI] [URL]

Abstract: The Multi-Object Optical and Near-infrared Spectrograph (MOONS) will cover the Very Large Telescope's (VLT) field of view with 1000 fibres. The fibres will be mounted on fibre positioning units (FPU) implemented as two-DOF robot arms to ensure a homogeneous coverage of the 500 square arcmin field of view. To accurately and fast determine the position of the 1000 fibres a metrology system has been designed. This paper presents the hardware and software design and performance of the metrology system. The metrology system is based on the analysis of images taken by a circular array of 12 cameras located close to the VLTs derotator ring around the Nasmyth focus. The system includes 24 individually adjustable lamps. The fibre positions are measured through dedicated metrology targets mounted on top of the FPUs and fiducial markers connected to the FPU support plate which are imaged at the same time. A flexible pipeline based on VLT standards is used to process the images. The position accuracy was determined to 5 μm in the central region of the images. Including the outer regions the overall positioning accuracy is 25 μm. The MOONS metrology system is fully set up with a working prototype. The results in parts of the images are already excellent. By using upcoming hardware and improving the calibration it is expected to fulfil the accuracy requirement over the complete field of view for all metrology cameras.

BibTeX:

@inproceedings{Drass2016,
  author = {Holger Drass and Leonardo Vanzi and Miguel Torres-Torriti and Rolando Dünner and Tzu-Chiang Shen and Francisco Belmar and Lousie Dauvin and Tomás Staig and Jonathan Antognini and Mauricio Flores and Yerko Luco and Clémentine Béchet and David Boettger and Steven Beard and David Montgomery and Stephen Watson and Alexandre Cabral and Mahmoud Hayati and Manuel Abreu and Phil Rees II and Michele Cirasuolo and William Taylor and Alasdair Fairley},
  editor = {Christopher J. Evans and Luc Simard and Hideki Takami},
  title = {Implementation and performance of the metrology system for the multi-object optical and near-infrared spectrograph MOONS},
  booktitle = {Ground-based and Airborne Instrumentation for Astronomy VI},
  publisher = {SPIE},
  year = {2016},
  volume = {9908},
  pages = {2498 -- 2507},
  url = {https://doi.org/10.1117/12.2232654},
  doi = {10.1117/12.2232654}
}

Prado AJ, Cheein FA and Torres-Torriti M (2016), "Probabilistic approaches for self-tuning path tracking controllers using prior knowledge of the terrain", In Proceedings of the 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 9--14 October 2016. Daejeon, Korea, Oct, 2016. , pp. 3095-3100.

[Abstract] [BibTeX] [DOI]

Abstract: Nowadays, agricultural and mining industry applications require saving energy in mobile robotic tasks. This critical issue encouraged us to enhance the performance of path tracking controllers during manoeuvring over slippery and rough terrains. In this scenario, we propose probabilistic approaches under machine learning schemes in order to optimally self-tune the controller. The approaches are real time implemented and tested in a mining machinery skid steer loader Cat® 262C under gravel and muddy terrains (and their transitions). Finally, experimental results presented in this work show that the performance of the controller enhances up to 20% (average) without compromising saturations in the actuators.

BibTeX:

@inproceedings{Prado2016,
  author = {Prado, Alvaro Javier and Cheein, Fernando Auat and Torres-Torriti, Miguel},
  title = {Probabilistic approaches for self-tuning path tracking controllers using prior knowledge of the terrain},
  booktitle = {Proceedings of the 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 9--14 October 2016},
  year = {2016},
  pages = {3095-3100},
  doi = {10.1109/IROS.2016.7759479}
}

Cheein FA, Blazic S and Torres-Torriti M (2015), "Computational approaches for improving the performance of path tracking controllers for mobile robots", In Proceedings of the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS),. Hamburg, Germany, Sep., 2015. , pp. 6495-6500.

[Abstract] [BibTeX] [DOI]

Abstract: Performance of path tracking controllers for mobile robots is usually constrained to the tuning of a set of gains within previously known boundaries. In industrial applications, controller tuning is a time consuming task, which is especially critical when the gain values have a considerable impact on the use of the robot's energy resources. In this paper, we propose a set of approaches to automatically improve the performance of well-known path tracking controllers used for agricultural applications of automated agricultural machinery. The effect of the proposed strategy can be better appreciated during the transient response of the robot when it has to maneuver along a non-kinematically compatible path. The results presented in this work show that the robot's path tracking performance is improved up to 15% using the proposed approaches.

BibTeX:

@inproceedings{Cheein2015a,
  author = {Cheein, Fernando Auat and Blazic, Saso and Torres-Torriti, Miguel},
  title = {Computational approaches for improving the performance of path tracking controllers for mobile robots},
  booktitle = {Proceedings of the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS),},
  year = {2015},
  pages = {6495-6500},
  doi = {10.1109/IROS.2015.7354305}
}

Cheein FA, Herrera D, Gimenez J, Carelli R, Torres-Torriti M, Rosell-Polo JR, Escolà A and Arnó J (2015), "Human-robot interaction in precision agriculture: Sharing the workspace with service units", In Proceedings of the 2015 IEEE International Conference on Industrial Technology (ICIT). Seville, Spain, March, 2015. , pp. 289-295.

[Abstract] [BibTeX] [DOI]

Abstract: Currently, Chile and Argentina experience serious challenges that affect their agricultural productivity. For example, in Chile, the loss of farmable field due to recent earthquakes, and volcanic eruptions as well as the loss of water reserves due to climate changes are affecting the agriculture. Additionally, both countries are facing a same problem: the loss of human labor force. Field workers are migrating from the farm to other fields in the industry which offer them more stable and more profitable jobs (like the mining industry in Chile, or car assembling lines in Argentina). In this adverse scenario, it becomes necessary to introduce and develop agricultural automation and sensing technologies for both primary (harvesting, seeding, fertilizing, spraying) and secondary tasks (grove supervision, weed detection, hauling, mowing). However, fully robotized farms are not yet a possibility since the transition from human labor force dependent farming to autonomous farming needs to be smooth and requires legal regulation not yet in discussion. In this paper, we summarize the state of the art in human-robot interaction in farmable fields, with emphasis in the current constrains associated with flexible automatization of farms in Argentina and Chile. In particular, we introduce the guidelines for designing a humanrobot interaction strategy for harvesting tasks, that could be used for other agricultural tasks.

BibTeX:

@inproceedings{Cheein2015,
  author = {Cheein, Fernando Auat and Herrera, Daniel and Gimenez, Javier and Carelli, Ricardo and Torres-Torriti, Miguel and Rosell-Polo, Joan R. and Escolà, Alexandre and Arnó, Jaume},
  title = {Human-robot interaction in precision agriculture: Sharing the workspace with service units},
  booktitle = {Proceedings of the 2015 IEEE International Conference on Industrial Technology (ICIT)},
  year = {2015},
  pages = {289--295},
  doi = {10.1109/ICIT.2015.7125113}
}

Torres-Torriti M, Vanzi L, Dünner R, Belmar F, Dauvin L, Chen T-C, Cirasuolo M, Taylor W, Schnetler H, Montgomery D, Philip Rees II and Cabral A (2014), "The metrology system for the multi-object optical and near-infrared spectrograph MOONS", In Ground-based and Airborne Instrumentation for Astronomy V. Vol. 9147, pp. 2763 - 2769. SPIE.

[Abstract] [BibTeX] [DOI] [URL]

Abstract: The Multi-Object Optical and Near-infrared Spectrograph (MOONS) is a new fiber-fed spectrograph for the VLT. MOONS will exploit the full 500 square arcmin field of view offered by the Nasmyth focus of VLT and will be equipped with two dual-arm spectrographs covering the wavelength range 0.8 µm-1.8 μm, with a possible extension down to 0.5 μm. Each double-arm spectrograph will produce spectra for 250 targets simultaneously, each with its own dedicated sky fiber for optimal sky subtraction. The system will have both a medium resolution (R 3000 - 5000) mode and a high resolution (R 20000) mode to allow detailed dynamical and chemical studies. To ensure the accurate positioning of the 500 fiber pairs over the focal plane that has 880 mm in diameter, a metrology system has been designed to provide position measurements within 7.5 μm considering that the final positioning accuracy of each fiber with respect to the target object must be less than 15 μm. The metrology system is composed by a circular array of 12 cameras located at VLT’s de-rotator ring around the Nasmyth focus. The paper presents the design of the metrology system and discusses the proposed methodology to align multiple the views of the focal plane array.

BibTeX:

@inproceedings{TorresTorriti2014,
  author = {Miguel Torres-Torriti and Leonardo Vanzi and Rolando Dünner and Francisco Belmar and Louise Dauvin and Tzu-Chiang Chen and Michele Cirasuolo and William Taylor and Hermine Schnetler and David Montgomery and Philip Rees II and Alexandre Cabral},
  editor = {Suzanne K. Ramsay and Ian S. McLean and Hideki Takami},
  title = {The metrology system for the multi-object optical and near-infrared spectrograph MOONS},
  booktitle = {Ground-based and Airborne Instrumentation for Astronomy V},
  publisher = {SPIE},
  year = {2014},
  volume = {9147},
  pages = {2763 -- 2769},
  url = {https://doi.org/10.1117/12.2055686},
  doi = {10.1117/12.2055686}
}

Aguilera S, Torres-Torriti M and Auat F (2014), "Modeling of skid-steer mobile manipulators using spatial vector algebra and experimental validation with a compact loader", In Proceedings of the 2014 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 14--18 September 2014. Chicago, Illinois, Sep., 2014. , pp. 1649-1655.

[Abstract] [BibTeX] [DOI]

Abstract: The present work models the dynamics of general skid-steer mobile manipulators using the formalism and tools of the spatial vectors algebra introduced by Featherstone. The model built is validated using inertial measurements obtained during field tests with a compact skid-steer loader. The paper demonstrates the benefits of using the spatial vector algebra formulation, showing that this modeling approach allows to integrate traction forces and study the arm-vehicle, as well as vehicle-ground interactions in a single model. This feature is not possible with many other of the existing modeling approaches and simulation tools, thus opens the way to research on mechanically more complex robot designs and their controllers. It is to be noted that most of the existing models and simulations of mobile manipulators consider two-wheeled differentially driven bases and avoid accurate models of skid-steering bases because of the complexity of simulating wheels that skid while rolling. However, skid-steer traction is common in most of the industrial construction and mining machinery because of their simpler mechanics, high reliability, and better mobility in rough terrains. Hence, the development of physically accurate models of skid-steer manipulators is fundamental. We chose to validate the model using a Cat^® 262C compact-skid steer loader instead of a small mobile manipulator common in robotics research laboratory to highlight the usefulness of the presented model and the spatial vector algebra approach.

BibTeX:

@inproceedings{Aguilera2014,
  author = {Aguilera, Sergio and Torres-Torriti, Miguel and Auat, Fernando},
  title = {Modeling of skid-steer mobile manipulators using spatial vector algebra and experimental validation with a compact loader},
  booktitle = {Proceedings of the 2014 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 14--18 September 2014},
  year = {2014},
  pages = {1649-1655},
  doi = {10.1109/IROS.2014.6942776}
}

Cirasuolo M, Afonso J, Bender R, Bonifacio P, Evans C, Kaper L, Oliva E, Vanzi L, Abreu M, Atad-Ettedgui E, Babusiaux C, Bauer FE, Best P, Bezawada N, Bryson IR, Cabral A, Caputi K, Centrone M, Chemla F, Cimatti A, Cioni M-R, Clementini G, Coelho J, Daddi E, Dunlop JS, Feltzing S, Ferguson A, Flores H, Fontana A, Fynbo J, Garilli B, Glauser AM, Guinouard I, Hammer J-F, Hastings PR, Hess H-J, Ivison RJ, Jagourel P, Jarvis M, Kauffman G, Lawrence A, Lee D, Causi GL, Lilly S, Lorenzetti D, Maiolino R, Mannucci F, McLure R, Minniti D, Montgomery D, Muschielok B, Nandra K, Navarro R, Norberg P, Origlia L, Padilla N, Peacock J, Pedicini F, Pentericci L, Pragt J, Puech M, Randich S, Renzini A, Ryde N, Rodrigues M, Royer F, Saglia R, Sánchez A, Schnetler H, Sobral D, Speziali R, Todd S, Tolstoy E, Torres-Torriti M, Venema L, Vitali F, Wegner M, Wells M, Wild V and Wright G (2012), "MOONS: a multi-object optical and near-infrared spectrograph for the VLT", In Ground-based and Airborne Instrumentation for Astronomy IV. Vol. 8446, pp. 243 - 251. SPIE.

[Abstract] [BibTeX] [DOI] [URL]

Abstract: MOONS is a new conceptual design for a Multi-Object Optical and Near-infrared Spectrograph for the Very Large
Telescope (VLT), selected by ESO for a Phase A study. The baseline design consists of 1000 fibers deployable over a
field of view of 500 square arcmin, the largest patrol field offered by the Nasmyth focus at the VLT. The total
wavelength coverage is 0.8μm-1.8μm and two resolution modes: medium resolution and high resolution. In the medium
resolution mode (R 4,000-6,000) the entire wavelength range 0.8μm-1.8μm is observed simultaneously, while the high
resolution mode covers simultaneously three selected spectral regions: one around the CaII triplet (at R 8,000) to
measure radial velocities, and two regions at R 20,000 one in the J-band and one in the H-band, for detailed
measurements of chemical abundances.
The grasp of the 8.2m Very Large Telescope (VLT) combined with the large multiplex and wavelength coverage of
MOONS – extending into the near-IR – will provide the observational power necessary to study galaxy formation and
evolution over the entire history of the Universe, from our Milky Way, through the redshift desert and up to the epoch
of re-ionization at z<8-9. At the same time, the high spectral resolution mode will allow astronomers to study chemical
abundances of stars in our Galaxy, in particular in the highly obscured regions of the Bulge, and provide the necessary
follow-up of the Gaia mission. Such characteristics and versatility make MOONS the long-awaited workhorse near-IR
MOS for the VLT, which will perfectly complement optical spectroscopy performed by FLAMES and VIMOS.

BibTeX:

@inproceedings{Cirasuolo2012,
  author = {M. Cirasuolo and J. Afonso and R. Bender and P. Bonifacio and C. Evans and L. Kaper and Ernesto Oliva and Leonardo Vanzi and Manuel Abreu and Eli Atad-Ettedgui and Carine Babusiaux and Franz E. Bauer and Philip Best and Naidu Bezawada and Ian R. Bryson and Alexandre Cabral and Karina Caputi and Mauro Centrone and Fanny Chemla and Andrea Cimatti and Maria-Rosa Cioni and Gisella Clementini and João Coelho and Emanuele Daddi and James S. Dunlop and Sofia Feltzing and Annette Ferguson and Hector Flores and Adriano Fontana and Johan Fynbo and Bianca Garilli and Adrian M. Glauser and Isabelle Guinouard and Jean-François Hammer and Peter R. Hastings and Hans-Joachim Hess and Rob J. Ivison and Pascal Jagourel and Matt Jarvis and G. Kauffman and A. Lawrence and D. Lee and G. Li Causi and S. Lilly and D. Lorenzetti and R. Maiolino and F. Mannucci and R. McLure and D. Minniti and D. Montgomery and B. Muschielok and K. Nandra and R. Navarro and P. Norberg and L. Origlia and N. Padilla and J. Peacock and F. Pedicini and L. Pentericci and J. Pragt and M. Puech and S. Randich and A. Renzini and N. Ryde and M. Rodrigues and F. Royer and R. Saglia and A. Sánchez and H. Schnetler and D. Sobral and R. Speziali and S. Todd and E. Tolstoy and M. Torres-Torriti and L. Venema and F. Vitali and M. Wegner and M. Wells and V. Wild and G. Wright},
  editor = {Ian S. McLean and Suzanne K. Ramsay and Hideki Takami},
  title = {MOONS: a multi-object optical and near-infrared spectrograph for the VLT},
  booktitle = {Ground-based and Airborne Instrumentation for Astronomy IV},
  publisher = {SPIE},
  year = {2012},
  volume = {8446},
  pages = {243 -- 251},
  url = {https://doi.org/10.1117/12.925871},
  doi = {10.1117/12.925871}
}

Larraín-Muñoz G and Torres-Torriti M (2012), "A Python Package for Robot Simulation", In Proceedings of the 15^th Latin American Control Conference, 23-26 October 2012. Lima, Perú, October, 2012.

[BibTeX]

BibTeX:

@inproceedings{LarrainMunoz2012,
  author = {Germán Larraín-Muñoz and Miguel Torres-Torriti},
  title = {A Python Package for Robot Simulation},
  booktitle = {Proceedings of the 15^th Latin American Control Conference, 23-26 October 2012},
  year = {2012}
}

Gálvez-Herrera R and Torres-Torriti M (2012), "Diseño de un Sistema Integrado de Escaneo 3D y Prototipado Rápido Utilizando Visión Activa y un Manipulador Robótico", In Proceedings of the 15^th Latin American Control Conference, 23-26 October 2012. Lima, Perú, October, 2012.

[BibTeX]

BibTeX:

@inproceedings{Galvez2012,
  author = {Robinson Gálvez-Herrera and Miguel Torres-Torriti},
  title = {Diseño de un Sistema Integrado de Escaneo 3D y Prototipado Rápido Utilizando Visión Activa y un Manipulador Robótico},
  booktitle = {Proceedings of the 15^th Latin American Control Conference, 23-26 October 2012},
  year = {2012}
}

Arredondo T, Castillo P, Benapres P, Quiroz J and Torres M (2011), "A Biologically Inspired Memory in a Multi-agent Based Robotic Architecture", In Proceedings of the 2011 IEEE 23^rd International Conference on Tools with Artificial Intelligence (ICTAI), 7--9 November 2011. Boca Raton, Florida, November, 2011. , pp. 344-351.