Alejandro Ramirez-Serrano

The University of Calgary | HBI · Department of Mechanical and Manufacturing Engineering

In tilt-rotor UAVs, both the fuselage and tilting rotors contribute to the vehicle’s rotational motion. Consequently, the system’s dynamics rise to a highly-nonlinear system, making it challenging to find feasible and desired control solutions. The common control practices devise a logic-based controller to switch between different flight modes or...

This paper presents an optimized robust trajectory control system for an autonomous tiltrotor bi-copter based on an incremental nonlinear dynamic inversion (INDI) strategy combined with a set of PID/PD controllers. The methodology includes a lower level, fast attitude control action using an incremental nonlinear dynamic inversion (INDI) strategy,...

In tilt-rotor UAVs, both the fuselage and tilting rotors contribute to the vehicle's rotational motion. Consequently, the system's dynamics rise to a highly-nonlinear system, making it challenging to find feasible and desired control solutions. The common control practices devise a logic-based controller to switch between different flight modes or...

View Video Presentation: https://doi.org/10.2514/6.2022-3792.vid A project aimed at developing and flight-testing a small-scale supersonic uncrewed aerial vehicle (SSUAV) at the University of Calgary is introduced and current progress described. The project's goals, design trade-offs, and future plans are explained. A six degree-of-freedom mathemat...

The National Aeronautics and Space Administration’s (NASA’s) Robotics Operations branch at the Johnson Space Center is entrusted with the planning and execution of operations on-board the International Space Station (ISS) using the Canadarm2, Dextre, and Mobile Transporter robots. While the most exciting part of the team’s work (the aspect most oft...

Human-robot collaborative systems have emerged as a solution that aims to satisfy the current demand of highly personalized products by combining the skills of humans and robots within a shared workspace. However, the safety of human operators is of major concern when located next to a robotic companion. The objective of this article is to present...

Visual Simultaneous Localization and Mapping (SLAM) technologies based on point features achieve high positioning accuracy and complete map construction. However, despite their time efficiency and accuracy, such SLAM systems are prone to instability and even failure in poor texture environments. In this paper, line features are integrated with poin...

The implementation of human-robot collaborative systems in industrial environments have widely extended during the last five years, from manufacturing applications reproduced in laboratory facilities or digital simulations to real automotive shop floors. Commonly, one way to guide their design has been through the adoption of international standard...

View Video Presentation: https://doi.org/10.2514/6.2021-2415.vid A verification and validation assessment of an open-source framework, the Stanford University Aerospace Vehicle Environment (SUAVE), and its individual modules, for the multidisciplinary design and optimization of small-scale, supersonic, unmanned aerial vehicles (UAVs) was performed....

The National Aeronautics and Space Administration’s (NASA’s) Robotics Operations branch at the Johnson Space Center is entrusted with the planning and execution of operations on-board the International Space Station (ISS) using the Canadarm2 and Dextre robots. While the most exciting part of the team’s work (the aspect most often shown on televisio...

Robot perception in dynamic confined unstructured environments is a challenging task due to unanticipated changes that take place in the surroundings. Although 3D perception sensors are able to capture terrain topology with high precision, the interim variations between collected sensor data that are caused due to the motion of moving entities with...

The limited dexterity that existing hand prostheses provide to users contrasts with the manipulation abilities exhibited by state-of-the-art robot hands. This paper presents an underactuated robot hand with in-hand manipulation capabilities to demonstrate the use of underactuation in the development of effective hand replacements. The paper describ...

Object extraction is an important tool in many applications within the image processing and computer vision communities. You Only Look Once version 3 (YOLOv3) has been extensively applied to many fields as a state-of-the-art technique for object semantic detection. Despite its numerous characteristics, YOLOv3 has to be combined with appropriate ima...

Aircraft concept development is the process of generating feasible concepts/configurations and selecting the one that best fulfills the requirements. It is a decisive step as it significantly affects the entire design process and ultimately the aircraft performance. Ideally, all possible configurations are considered during the concept development...

Hybrid aircraft are systems capable of flying as either fixed-wing aircraft or rotorcraft, as well as transition between these modes. Nowadays, hybrid aircraft have many potential applications as they consolidate some of the advantages of fixed-wing aircraft and rotorcraft. Despite the abundant knowledge on designing fixed-wing aircraft, designing...

Multi-modal locomotion (e.g. terrestrial, aerial, and aquatic) is gaining increasing interest in robotics research as it improves the robots environmental adaptability, locomotion versatility, and operational flexibility. Within the terrestrial multiple locomotion robots, the advantage of hybrid robots stems from their multiple (two or more) locomo...

Selecting a baseline aircraft configuration during the aircraft conceptual design phase is crucial as it significantly affects different aspects of the aircraft such as its performance, design and development process. Generally, making a decision about the baseline configuration in the aerospace industry is a very difficult process. Ideally, based...

The evolution in the missions’ complexity of both military aircraft and Unmanned Aerial Vehicles (UAVs) and the increase in civilian air-traffic, with limited runways, have led to the development of a new category of aircraft called Transitional Aircraft (TA). The goal of TA is to take advantages of both the characteristics of fixed-wing aircraft,...

Advanced empirical, and physical-based tyre models have proven to be accurate for simulating tyre dynamics; however, these tyre models typically require expensive and intensive tyre parameterisation. Recent research into wheeled unmanned ground vehicles requiring vertical force analysis has shown good results using a simple linear spring model for...

This paper proposes a criterion based method to make possible the autonomous locomotion mode transition of ground hybrid robots. The criterion is developed based on both the internal states of robots (energy) and the external environmental information (obstacle height), which has been verified via the energy consumption comparison of two simplified...

This paper proposes an energy consumption criterion to realize the locomotion mode transition of hybrid ground robots, which particularly focuses on gait and energy analysis of a leg-tracked quadruped robot. The proposed criterion uses both the internal states of the robot and the external environmental information to determine the most energy effi...

This work describes a modified Nonlinear Model Predictive Control (NMPC) to address control performance issues that arise when NMPC is applied on unmanned aerial vehicles. The proposed NMPC typically identifies lower cost control options within a set optimization time frame thus producing more stable and robust control. We also introduce an alterna...

The use of robotics in Urban Search and Rescue (USAR) is growing steadily from their initial inception during the 2001 World Trade Centre incident. Despite years of progress, the core design of robots currently in use for USAR purposes has deviated little, favoring software and control development and optimization of the basic robot template to imp...

This work describes an extension to traditional Model Predictive Control (MPC) in order to address control performance issues that arise when MPC is applied on Unmanned Aerial Vehicles (UAVs). The Enhanced MPC typically identifies lower cost control options within a given time frame thus producing more stable control. We also introduce an alternati...

With quadrotor use seeing extensive growth in recent years, the autonomous control of these Unmanned Aerial Vehicles (UAVs) is an increasing relevant and intersting field. In this paper a linear state-space approach at designing a stable hover controller in the presence of disturbances is presented along with simulation of control system performanc...

High-speed navigation of autonomous Unmanned Ground Vehicles (UGVs) in rough unknown terrains requires the detection and identification of the terrain in order to make effective navigation decisions. This paper investigates a geometrical approach to identifying terrain based on its roughness using the terrain elevations from a point cloud generated...

In human relationships, responsiveness---behaving in a sensitive manner that is supportive of another person's needs---plays a major role in any interaction that involves effective communication, caregiving, and social support. Perceiving one's partner ...

In this paper, we investigate the multiple attribute decision making problems in which the attribute weights are usually correlative, attribute values take the form of linguistic variables, some new methods are developed. Then a new aggregation operator called induced generalized 2-tuple linguistic choquet ordered averaging ( IG-2TCOA) operator is...

An adaptive nonlinear robust controller for a novel highly maneuverable dual-ducted UAV is considered in this paper. The dynamics of the system is highly nonlinear and not originally in the control-affine form. At first the equations governing the dynamics of the system are extracted. Then a change of variables is proposed to transform the dynamic...

A new non-pharmacological method of distraction was tested with 57 children during their annual flu vaccination. Given children's growing enthusiasm for technological devices, a humanoid robot was programmed to interact with them while a nurse administered the vaccination. Children smiled more often with the robot, as compared to the control condit...

In this paper, a dynamic model of vertical take-off and landing (VTOL) aerial vehicles, having lateral and longitudinal rotor tilting mechanism, is first developed using a Newton–Euler formulation. Then an integral backstepping (IB) control technique is proposed to improve the pitch, yaw, and roll stability of the vehicle. Such control mechanisms e...

Objective: Millions of children in North America receive an annual flu vaccination, many of whom are at risk of experiencing severe distress. Millions of children also use technologically advanced devices such as computers and cell phones. Based on this familiarity, we introduced another sophisticated device - a humanoid robot - to interact with c...

This paper addresses the problem of determining the maximum allowable speed (V max ) of Unmanned Ground Vehicles (UGVs) traversing off-road heterogeneous rough/complex terrain. The maximum speed is calculated based on online terrain assessment and the vehicle’s characteristics; this speed achieves the high speed navigation without exceeding a prede...

Consider the problem of control selection in complex dynamical and environmental scenarios where model predictive control (MPC) proves particularly effective. As the performance of MPC is highly dependent on the efficiency of its incorporated search algorithm, this work examined hill climbing as an alternative to traditional systematic or random se...

Enabling high speed navigation of Unmanned Ground Vehicles (UGVs) in unknown rough terrain where limited or no information is available in advance requires the assessment of terrain in front of the UGV. Attempts have been made to predict the forces the terrain exerts on the UGV for the purpose of determining the maximum allowable velocity for a giv...

This paper investigates a new method of modeling and simulation of a two wheeled Mobile Manipulators (MMs) system each equipped with a 6 DOF arm. Such system modeled in Matlab/Simulink (Simmechanic) environment is used to transport objects without explicit communication between the MMs. MMs cooperation control has received big interest in the last...

To predict changes in the shape of the breast in different imaging devices, a Coupled Eulerian-Lagrangian (CEL) mechanical model is developed. The CEL method allows for a more adequate representation of the very large deformations experienced by the soft and incompressible tissues of the breast. The mechanical response of the tissues is based on ad...

Consumer preferences and information on product choice behavior can be of significant value in the development processes of innovative products. In this paper, product customization evaluation and selection model is introduced to support imprecision inherent of qualitative inputs from customers and designers in the decision making process. Focusing...

The unmanned aerial vehicle (UAV) under investigation (Evader) has two rotors with the capability of independent lateral and longitudinal rotor tilting. The dynamic model of this vehicle is derived based on the Newton-Euler equations. The parametric uncertainties are considered in the model and an adaptive control law based on feedback linearizatio...

Cooperation control between human's and mobile manipulators has received big interest in the last few years. Mobile manipulators (MMs) have been suggested for various applications such as tasks involving hazardous environments, explosive handling, waste management, outdoor exploration and space operations. This paper describes a novel control algor...

Current Unmanned Vehicle (UV) navigation systems are capable of autonomous navigation among disperse obstacles. However, these systems may fail to guide vehicles through highly confined environments because they do not explicitly consider the geometry of the vehicle in the navigation task. This paper presents a methodology that enables the navigati...

Product concept generation and evaluation in a product development environment has been identified as the two major activities needed for obtaining an optimal design scheme. Product conceptual design is of critical importance in design through customer involvement for the systematic and simultaneous consideration on the impact of design decisions o...

Just as human-human behavior and interactions are important to study, human-robot interactions will take more prominence in the near future. These interactions will not only be in one direction, robots helping humans, but they will also be bidirectional with humans helping robots. This study examined the interactions between children and robots by...

This work presents a direct approximate-adaptive control, using CMAC nonlinear approximators, for an experimental prototype quadrotor helicopter. The method updates adaptive parameters, the CMAC weights, as to achieve both adaptation to unknown payloads and robustness to disturbances. Previously proposed weight-update methods, such as e-modificatio...

Mini-vertical take-off and landing aircraft have a wide range of potential applications in urban areas. In flights in confined spaces, however, the aerodynamics of the lifting devices (e.g., tilted ducted fans) change which significantly affects the flight performance. Therefore, for a successful flight, a model is required to provide the control s...

Centuries ago, the existence of life was explained by the presence of a soul (Tylor, 1871). Known as animism, this term was re-defined in the 1970s by Piaget as young children's beliefs that inanimate objects are capable of actions and have life-like qualities. With the development of robots in the 21st century, researchers have begun examining whe...

The researcher then exited and observed the child’s behaviors on the laptop. A similar number of children, who did not hear this introduction, formed the comparison group. As soon as children in each group were alone with the robot arm, it began stacking blocks. A significantly larger number of children in the introduction group (n = 17, 53.1%), th...

The nonlinear and open-loop unstable dynamics of a quadrotor helicopter makes a control system design non-trivial. However, even more difficulty lies in adapting to an uncertain dynamic model and unknown payloads while remaining robust to significant buffeting wind disturbances. Fuzzy-adaptive or neural-adaptive control offer possible solutions, ex...

Human and mobile manipulators cooperation control has received big interest in the last few years. Mobile manipulators (MMs) have been suggested for various applications such as tasks involving hazardous environments, explosive handling, waste management, outdoor exploration and space operations; however most research in Human-MMs cooperation has c...

As the development of autonomous robots has moved towards creating social robots, children’s interactions with robots will soon become a central focus in research. The purpose of this study was to examine how children think about and attribute features of friendship to a robot after a brief interaction with one. Children visiting a science centre l...

Mecanum wheels give vehicles/robots omni-directional capabilities, while regular wheels don't. The omni-directionality that such wheels provide makes the vehicle extremely maneuverable, which could be helpful in different indoor and outdoor applications. However, current Mecanum wheels designs can only operate on flat hard surfaces, and perform ver...

As the development of autonomous robots has moved towards creating social robots, children’s interactions with robots will soon need to be investigated. This paper examines how children think about and attribute features of friendship to a robot. A total of 184 children between ages 5 to 16 years visiting a science centre were randomly selected to...

This paper addresses the problem of determining the maximum allowable speed (V) of a vehicle traversing unknown off-road terrains. The calculated maximum speed achieves the fastest navigation without exceeding an allowable range of transmitted force (Fall) to the vehicle's frame. The proposed system enables the vehicle to transit between different...

Mecanum wheels give vehicles and robots autonomous omni-directional capabilities, while regular wheels don’t. The omni-directionality that such wheels provide makes the vehicle extremely maneuverable, which could be very helpful in different indoor and outdoor applications. However, current Mecanum wheel designs can only operate on flat hard surfac...

Centuries ago, the existence of life was explained by the presence of a soul [1]. Known as animism, this term was re-defined in the 1970s by Piaget as young children's beliefs that inanimate objects are capable of actions and have lifelike qualities. With the development of robots in the 21st century, researchers have yet to examine whether animism...

This study examined the interactions between children and robots by observing whether children help a robot complete a task under five conditions to determine which elicited the most help. Each condition had an experimental and control group, with 20-32 children (even number of boys and girls) in each group. Visitors to a science centre located in...

This paper presents a new, computationally inexpensive, terrain roughness assessment technique. The technique, targeted for high speed unmanned ground vehicles (UGVs), considers no previous knowledge about the terrain but a priori knowledge about the vehicle's characteristics such as damping ratio, natural frequency and wheel configuration. The app...

This paper examines ground/wall effects on a ducted fan, with the aim to improve the handling quality of an unmanned aerial vehicle targeted for operations in confined spaces. In order to do this, flow field at different configurations of the fan-ground-wall is visualized computationally in Fluent. Herein the standard k-ε model and the non-equilibr...

This study examined the interactions between children and robots by observing whether children help a robot complete a task under five conditions to determine which elicited the most help. Each condition had an experimental and control group, with 20-32 children (even number of boys and girls) in each group. Visitors to a science centre located in...

Mecanum wheels give vehicles/robots omni-directional capabilities, while regular wheels don't. The omni-directionality that such wheels provide makes the vehicle extremely maneuverable, which could be helpful in different indoor and outdoor applications. However, current Mecanum wheels designs can only operate on flat hard surfaces, and perform ver...

This paper presents a Modular Architecture for Robotic Control (MARC) for unconventional Unmanned Vehicle Systems (UVS) with search and rescue applications. The MARC architecture is able to produce complex UVS behaviors with the interaction of multiple independent modular controllers, which are extremely difficult or impossible to execute via tradi...

We present a novel perception system for mapping of indoor/outdoor environments with an unmanned ground vehicle (UGV). The system uses image classification techniques to determine the operational environment of theUGV (indoor or outdoor). Based on the classification results, the appropriate mapping system is then deployed.Image features are extract...

The use of robotics in Urban Search and Rescue (USAR) is growing steadily from their initial inception during the 2001 World Trade Centre incident. Despite years of progress, the core design of robots currently in use for USAR purposes has deviated little, favoring software/control development and optimization of the basic robot template to improve...

In many applications, localization systems are important to enable unmanned vehicles (UV) operate autonomously. An example of such applications is the exploration of unknown terrains, such as the zone of an earthquake or a similar disaster. In any such scenarios errors in the UV's sensors or systems used for localization may be present. Due to the...

This paper presents a modular architecture for robotic control (MARC) for unconventional unmanned aerial vehicles (UAV). MARC was developed for a double-ducted vertical take-off and landing (VTOL) vehicle, capable of maneuvering within densely obstructed environments. The focus of this paper is to present the characteristics of the MARC architectur...

This paper proposes a new adaptive neural network control to stabilize a quadrotor helicopter against modeling error and considerable wind disturbance. The new method is compared to both deadzone and e-modification adaptive techniques and through simulation demonstrates a clear improvement in terms of achieving a desired attitude and reducing weigh...

Purpose The purpose of this paper is to address the online localization of mobile (service) robots in real world dynamic environments. Most of the techniques developed so far have been designed for static environments. What is presented here is a novel technique for mobile robot localization in quasi‐dynamic environments. Design/methodology/approa...

This paper discusses the use of resource-bounded intelligent agents acting in (complex) manufacturing environments. Agents operate for the coordination of multitasks performed within the plant. In particular, we discuss the agents' operation selection problem. The agent's required capabilities requires effective design and implementation approaches...

Swarm robotics is a rising paradigm which aims at designing new robot artifacts by extracting engineering guidelines from Nature. The work presented here shows the use of a particular swarm of robots called swarm-bot for carrying out distributed missions of fetching and retrieval of objects. To solve this task, a high level description plan defined...

In this paper, we describe our experience using a Java-based platform to implement an emerging real-time distributed control model (IEC 61499). We provide a simple example of a control application that is distributed across two devices (Dallas Semiconductor TINI boards) and also investigate how this distributed implementation can be exploi