Mike Allenspach

Bio: Mike Allenspach is an academic researcher from ETH Zurich. The author has contributed to research in topics: Computer science & Control theory. The author has an hindex of 2, co-authored 7 publications receiving 19 citations. Previous affiliations of Mike Allenspach include Institute of Robotics and Intelligent Systems.

Design and optimal control of a tiltrotor micro aerial vehicle for efficient omnidirectional flight

Abstract: Omnidirectional micro aerial vehicles are a growing field of research, with demonstrated advantages for aerial interaction and uninhibited observation. While systems with complete pose omnidirectionality and high hover efficiency have been developed independently, a robust system that combines the two has not been demonstrated to date. This paper presents the design and optimal control of a novel omnidirectional vehicle that can exert a wrench in any orientation while maintaining efficient flight configurations. The system design is motivated by the result of a morphology design optimization. A six degrees of freedom optimal controller is derived, with an actuator allocation approach that implements task prioritization, and is robust to singularities. Flight experiments demonstrate and verify the system's capabilities.

Design and optimal control of a tiltrotor micro-aerial vehicle for efficient omnidirectional flight:

Abstract: Omnidirectional micro-aerial vehicles (MAVs) are a growing field of research, with demonstrated advantages for aerial interaction and uninhibited observation. While systems with complete pose omnid...

Model Predictive Control of a Convertible Tiltrotor Unmanned Aerial Vehicle

Abstract: This paper presents a Model Predictive Control (MPC) based control structure for a convertible Unmanned Aerial Vehicle (UAV) with fixed wings and tiltrotor thrust vectoring. The controller encompasses full flight envelope trajectory tracking, thereby optimally exploiting the aircraft's Vertical Take Off and Landing (VTOL) and cruising-forward flight capabilities. An adaptive control allocation is designed to handle the changing control authorities of the actuators and efficiently distribute the required control actions between propellers, tilt servos and control surfaces. Preliminary simulation results show the feasibility of the proposed control approach.

Human-State-Aware Controller for a Tethered Aerial Robot Guiding a Human by Physical Interaction

Abstract: With the rapid development of Aerial Physical Interaction, the possibility to have aerial robots physically interacting with humans is attracting a growing interest. In one of our previous works [1], we considered one of the first systems in which a human is physically connected to an aerial vehicle by a cable. There, we developed a compliant controller that allows the robot to pull the human toward a desired position using forces only as an indirect communication-channel. However, this controller is based on the robot-state only, which makes the system not adaptable to the human behavior, and in particular to their walking speed. This reduces the effectiveness and comfort of the guidance when the human is still far from the desired point. In this paper, we formally analyze the problem and propose a human-state-aware controller that includes a human’s velocity feedback. We theoretically prove and experimentally show that this method provides a more consistent guiding force which enhances the guiding experience.

Design of multirotor aerial vehicles: A taxonomy based on input allocation:

Abstract: This paper reviews the effect of multirotor aerial vehicle designs on their abilities in terms of tasks and system properties. We propose a general taxonomy to characterize and describe multirotor ...

Active Interaction Force Control for Contact-Based Inspection With a Fully Actuated Aerial Vehicle

Abstract: This article presents and validates active interaction force control and planning for fully actuated and omnidirectional aerial manipulation platforms, with the goal of aerial contact inspection in unstructured environments. We present a variable axis-selective impedance control which integrates direct force control for intentional interaction, using feedback from an on-board force sensor. The control approach aims to reject disturbances in free flight, while handling unintentional interaction and actively controlling desired interaction forces. A fully actuated and omnidirectional tilt-rotor aerial system is used to show capabilities of the control and planning methods. Experiments demonstrate disturbance rejection, push-and-slide interaction, and force-controlled interaction in different flight orientations. The system is validated as a tool for nondestructive testing of concrete infrastructure, and statistical results of interaction control performance are presented and discussed.

Active Interaction Force Control for Contact-Based Inspection with a Fully Actuated Aerial Vehicle.

Abstract: This paper presents and validates active interaction force control and planning for fully actuated and omnidirectional aerial manipulation platforms, with the goal of aerial contact inspection in unstructured environments. We present a variable axis-selective impedance control which integrates direct force control for intentional interaction, using feedback from an on-board force sensor. The control approach aims to reject disturbances in free flight, while handling unintentional interaction, and actively controlling desired interaction forces. A fully actuated and omnidirectional tilt-rotor aerial system is used to show capabilities of the control and planning methods. Experiments demonstrate disturbance rejection, push-and-slide interaction, and force controlled interaction in different flight orientations. The system is validated as a tool for non-destructive testing of concrete infrastructure, and statistical results of

MPC Flight Control for a Tilt-Rotor VTOL Aircraft

Abstract: This article presents a model predictive control (MPC) controller and its novel application to a hybrid tilt-quadrotor fixed-wing aircraft, which combines vertical takeoff and landing (VTOL) capabilities with high-speed forward flight. The developed MPC controller takes a velocity command from the pilot and then computes optimal attitude setpoints and propeller-tilt angles that are supplied to a fast inner attitude controller. A control allocation algorithm then maps the output of the inner attitude loop to actuator commands. The proposed MPC and control allocation of this article constitute a unified nonlinear control approach for tilt-rotor VTOL aircraft, valid in all flight modes and transitions in between. The whole approach is verified both in simulations and in real-world outdoor experiments with a remote controlled VTOL aircraft transitioning from hover to high speed and vice versa in a stable and controlled manner. Results show superior performance compared to the common binary-switch transition strategy between multicopter flight mode and the fixed-wing flight mode. The MPC controller also consistently performs better than a previously developed fused-PID control architecture in our tests.