Saunders C, Forshaw JL, Lappas VJ, Chiesa A, Parreira B, Biesbroek R (2014) Mission and Systems Design for the Debris Removal of Massive Satellites,
Kornienko A, Rieber J, Ott T, Geshnizjani R, Fichter W, Forshaw JL, Aglietti G (2016) Attitude Control System for Agile Spacecraft: Architecture, Analysis, and Verification,
Forshaw JL, Lappas VJ (2012) Transitional Control Architecture, Methodology, and Robustness for a Twin Helicopter Rotor Tailsitter,
Forshaw JL, Lappas VJ, Briggs P (2013) Indoor Experimentation and Flight Test Results for a Twin Rotor Tailsitter Unmanned Air Vehicle,
Saunders C, Forshaw JL (2013) Service Oriented Active Debris Removal: Business Plan for Future Active Debris Removal Missions, 0218771 Surrey Satellite Technology Limited
Forshaw JL, Aglietti G (2014) The EU Project RemoveDEBRIS,
Forshaw JL, Lappas VJ, Pisseloup A, Salmon T, Chabot T, Retat I, Barraclough S, Bradford A, Rotteveel J, Chaumette F, Pollini A, Steyn WH (2014) RemoveDEBRIS: A Low Cost R&D ADR Demonstration Mission,
Forshaw JL, Bamber DC, Turconi A, Palmer P, Gignac D, Troyas P, Sarris E, Margaronis K (2015) SpacePlan 2020: Identification and Assessment of Key Space Technologies towards 2020,
Inumoh LO, Horri N, Forshaw JL, Pechev A (2014) Bounded Gain-Scheduled LQR Satellite Control using a Tilted Wheel, IEEE Transactions on Aerospace and Electronic Systems50(3)pp. 1726-1738
Satellite attitude control is normally performed with actuators such as CMGs, reaction wheels. This research considers a novel type of 3-DOF actuator that uses a spinning wheel and tilt mechanism, which has less mass, more simplicity and is singularity-free during nominal operation in comparison to existing actuators. A novel high-performance bounded LQR control law is also presented which is capable of gain-scheduling its parameters. High-fidelity 3-DOF simulations demonstrate feasibility for both wheel and control law.
Saunders C, Chiesa A, Forshaw JL, Parreira B, Biesbroek R (2014) Results of a System Feasibility Study on a Heavy Active Debris Removal Mission,
Ghiglino P, Forshaw JL, Lappas VJ (2014) Online Evolutionary Swarm Algorithm for Self-Tuning Unmanned Flight Control Laws, AIAA Journal of Guidance, Control, and Dynamics38(4)pp. 772-782
Saunders C, Forshaw JL (2013) Service Oriented Active Debris Removal: System Concept Definition and Feasibility Assessment, 0206456 Surrey Satellite Technology Limited
Lappas VJ, Forshaw JL, Pisseloup A, Salmon T, Joffre E, Chabot T, Retat I, Axthelm R, Barraclough S, Ratcliffe A, Bradford A, Kadhem H, Navarathinam N, Rotteveel J, Bernal C, Chaumette F, Pollini A, Steyn WH (2014) RemoveDEBRIS: An EU Low Cost Demonstration Mission to Test ADR Technologies,
Forshaw JL, Lappas VJ, Briggs P (2014) Transitional Control Architecture and Methodology for a Twin Rotor Tailsitter, AIAA Journal of Guidance, Control, and Dynamics37(4)pp. 1289-1298
Forshaw JL, Lappas VJ (2012) Architecture and Systems Design of a Reusable Martian Twin Rotor Tailsitter, Acta Astronautica80(0)pp. 166-180
A rapidly developing field is that of tailsitters, aircraft capable of transitioning between horizontal and vertical flight, a premise that supports a diverse range of applications. Tailsitters can effortlessly land and hover at will, yet can also move at high speed between destinations making them ideal in undertaking 'multiple missions to land at multiple destinations far apart'. This paper considers how the concept of twin helicopter rotor tailsitters, such as QinetiQs Eye-On , can be adapted for use in a Martian environment. The mission architecture and system requirements for both reusable and single-use tailsitters are considered and 12 disparate subsystems or fields (including propulsion, power and aerodynamics) are designed using a high-level systems approach. The resulting tailsitter is capable of covering 100km and 450km in reusable and single-use architectures respectively. A docking station is also designed utilising a four stage process for deployment of the tailsitter. © 2012 Elsevier Ltd.
Inumoh LO, Pechev A, Horri N, Forshaw JL (2012) Three-Axis Attitude Control of a Satellite in Zero Momentum Mode Using a Tilted Wheel Methodology,
Forshaw JL, Lappas VJ (2011) High-Fidelity Modeling and Control of a Twin Helicopter Rotor Tailsitter,
Flight and ground segment software in university missions is often developed only after hardware has matured sufficiently towards flight configuration and also as bespoke codebases to address key subsystems in power, communications, attitude, and payload control with little commonality. This bespoke software process is often hardware specific, highly sequential, and costly in staff/monitory resources and, ultimately, development time. Within Surrey Space Centre (SSC), there are a number of satellite missions under development with similar delivery timelines that have overlapping requirements for the common tasks and additional payload handling. To address the needs of multiple missions with limited staff resources in a given delivery schedule, computing commonality for both flight and ground segment software is exploited by implementing a common set of flight tasks (or modules) which can be automatically generated into ground segment databases to deliver advanced debugging support during system end-to-end test (SEET) and operations. This paper focuses on the development, implementation, and testing of SSC?s common software framework on the Stellenbosch ADCS stack and OBC emulators for numerous missions including Alsat-1N, RemoveDebris, SME-SAT, and InflateSail. The framework uses a combination of open-source embedded and enterprise tools such as the FreeRTOS operating system coupled with rapid development templates used to auto-generate C and Python scripts offline from ?message databases?. In the flight software, a ?core? packet router thread forwards messages between threads for inter process communication (IPC). On the ground, this is complemented with an auto-generated PostgreSQL database and web interface to test, log, and display results in the SSC satellite operations centre. Profiling is performed using FreeRTOS primitives to manage module behaviour, context, time and memory ? especially important during integration. This new framework has allowed for flight and ground software to be developed in parallel across SSC?s current and future missions more efficiently, with fewer propagated errors, and increased consistency between the flight software, ground station and project documentation.
Massimiani C, forshaw J, aglietti G (2016) CubeSats as Artificial Debris Targets for Active Debris Removal Missions,
Chabot T, Kervendal E, Despré N, Kanani K, Vidal P, Monchieri E, Rebuffat D, Santandrea S, Forshaw JL, Pollini A, Majewski L (2015) Relative Navigation Challenges and Solutions for Autonomous Orbital Rendezvous,
Ghiglino P, Forshaw JL, Lappas VJ (2013) Online PID Self-Tuning Using an Evolutionary Swarm Algorithm with Experimental Quadrotor Flight Results,
Contracted by the European Commission in the frame of the EU?s Seventh Framework
Programme for Research (FP7), a wide European consortium has been working since 2013
towards the design of a low cost in-orbit demonstration called RemoveDEBRIS. With a targeted
launch date in the second quarter of 2016, the RemoveDEBRIS mission aims at demonstrating
key Active Debris Removal (ADR) technologies, including capture means (net and harpoon
firing on a distant target), relative navigation techniques (vision-based navigation sensors and
associated algorithms), and deorbiting technologies (drag sail deployment after the mission
followed by an uncontrolled reentry). In order to achieve these objectives, a micro satellite testbed
will be launched into a Low Earth Orbit, where it will deploy its own dedicated targets and
CubeSats to complete each demonstration. As part of its System Engineering role, Airbus
Defence and Space has been conducting the Mission Analysis studies for this unprecedented
mission. This paper will present a description of the RemoveDEBRIS demonstration objectives
and scenario and will present in detail some specific mission related analyses and trade-offs that
have driven the mission design.
Forshaw J, Aglietti G, Salmon T, Retat I, Roe M, Burgess C, Chabot T, Pisseloup A, Phipps A, Bernal C, Chaumette F, Pollini A, Steyn W (2016) Review of Final Payload Test Results for the RemoveDebris Active Debris Removal Mission,
Forshaw JL, Turconi A, Aglietti G, Gignac D, Macret J-L, Troyas P, Sarris E, Margaronis K (2016) Roadmapping for Europe: SpacePlan 2020 ? Final Results,
Inumoh LO, Forshaw JL, Lappas VJ, Horri N (2013) Three-Axis Tilted Wheel Experimental Results Using an Air-Bearing Table,
Jaffery MH, Shead L, Forshaw JL, Lappas VJ (2013) Experimental Quadrotor Flight Performance using Computationally Efficient and Recursively Feasible Linear Model Predictive Control, International Journal of Control86(12)pp. 2189-2202
A new linear model predictive control (MPC) algorithm in a state-space framework is presented based on the fusion of two past MPC control laws: steady-state optimal MPC (SSOMPC) and Laguerre optimal MPC (LOMPC). The new controller, SSLOMPC, is demonstrated to have improved feasibility, tracking performance and computation time than its predecessors. This is verified in both simulation and practical experimentation on a quadrotor unmanned air vehicle in an indoor motion-capture testbed. The performance of the control law is experimentally compared with proportional-integral-derivative (PID) and linear quadratic regulator (LQR) controllers in an unconstrained square manoeuvre. The use of soft control output and hard control input constraints is also examined in single and dual constrained manoeuvres. © 2013 Copyright Taylor and Francis Group, LLC.
Ghiglino, P, Forshaw JL, Lappas VJ (2015) OQTAL - Optimal Quaternion Tracking using Attitude Error Linearization, IEEE Transactions on Aerospace and Electronic Systems51(4)pp. 2715-2731
Forshaw JL (2012) Interim Report: Modelling, Control and Autopilot Design of a Twin Rotor Tailsitter Unmanned Air
System, Air Division, QinetiQ, UK
Forshaw JL (2010) Kalman Filtered Augmented GPS Guidance for UAV Development Platform Navigation, MEng Thesis,
Bamber DC, Forshaw JL, Frame TE, Aglietti G, Geshnizjani R, Goerries S, Kornienko A, Levenhagen J, Gao Y, Chanik A (2015) Absolute Attitude Determination System for a Spherical Air Bearing Testbed,
Forshaw JL (2016) The RemoveDebris ADR Mission: Overview of CubeSat ?Artificial Debris? Targets,
Visagie L, Forshaw JL, Frame T, Steyn WH, Lappas VJ (2014) A Miniaturised Attitude Control and Determination System for the QB50 and SME-SAT Missions,
Saunders C, Forshaw JL, Lappas VJ, Wade D, Iron D, Biesbroek R (2014) Business and Economic Considerations for Service Oriented Active Debris Removal Missions,
Forshaw JL, Aglietti G, Navarathinam N, Kadhem H, Salmon T, Joffre E, Chabot T, Retat I, Axthelm R, Barraclough S, Ratcliffe A, Bernal C, Chaumette F, Pollini A, Steyn WH (2015) An In-Orbit Active Debris Removal Mission ? RemoveDEBRIS: Pre-launch Update,
Forshaw JL (2013) Transitioning Flight Guidance and Control for a Twin Rotor Tailsitter Unmanned Air Vehicle, PhD Thesis,
Forshaw J, Aglietti G, Salmon T, Retat I, Roe M, Burgess C, Chabot T, Pisseloup A, Phipps A, Bernal C, Chaumette F, Pollini A, Steyn W (2017) Final Payload Test Results for the RemoveDebris Active Debris Removal Mission,Acta Astronautica138pp. 326-342
Since the beginning of the space era, a significant amount of debris has progressively been generated in space. Active Debris Removal
(ADR) missions have been suggested as a way of limiting and controlling future growth in orbital space debris by actively deploying
vehicles to remove debris. The European Commission FP7-sponsored RemoveDebris mission, which started in 2013, draws on the
expertise of some of Europe?s most prominent space institutions in order to demonstrate key ADR technologies in a cost effective
ambitious manner: net capture, harpoon capture, vision-based navigation, dragsail de-orbiting.
This paper provides an overview of some of the final payload test results before launch. A comprehensive test campaign is
underway on both payloads and platform. The tests aim to demonstrate both functional success of the experiments and that the
experiments can survive the space environment. Space environmental tests (EVT) include vibration, thermal, vacuum or thermalvacuum
(TVAC) and in some cases EMC and shock. The test flow differs for each payload and depends on the heritage of the
constituent payload parts. The paper will also provide an update to the launch, expected in 2017 from the International Space Station
(ISS), and test philosophy that has been influenced from the launch and prerequisite NASA safety review for the mission.
The RemoveDebris mission aims to be one of the world?s first in-orbit demonstrations of key technologies for active debris
removal and is a vital prerequisite to achieving the ultimate goal of a cleaner Earth orbital environment.