Enabling Unmanned Aerial Vehicles (Drones) to use Tools in Complex Dynamic Environments
This project is led by the University of Canterbury, funded by the New Zealand Ministry of Business, Innovation and Employment
Karl Stol, Bruce MacDonald, Shahab Kazemi, Nicholas Kay, Salim Al-zubaidi, Angus Lynch
Unmanned aerial vehicles (UAVs/drones) are revolutionising surveying and inspection tasks which once required manned aircraft, and are becoming a standard tool for a wide range of applications. However, one glaring omission is the ability to accurately use tools to perform precision tasks in high and hard-to-reach locations.
This research will design, build and demonstrate a compact UAV with precise six degrees-of-freedom positioning capability enabled by new control methods, airframe designs, aerodynamic models, and position estimation (visual odometry) in dynamically changing (windy) environments.
Rotor Configuration and Control of High Precision Drones
PhD Research
Salim Al-zubaidi. Supervisors: Karl Stol & Peter Xu
With the rise of the UAV use in interaction, the ability of the UAV to change the contact force instantaneously and the control of all axes independently became important aspect of the UAV performance.
This research aims to present a new UAV configuration with the potential for improved horizontal agility. An optimisation process is developed to maximise the horizontal bandwidth. A control algorithm will be developed to make use of the improved capabilities of the UAV.
Related:
- Enabling Unmanned Aerial Vehicles (Drones) to use Tools in Complex Dynamic Environments
- Experimental Validation of a UAV Configuration Optimisation Algorithm
- Drone Airframe Optimization
- Variable-Pitch Propellers for Highly Agile Drones
Read:
- Al-Zubaidi, S., Stol, K. “Analysis of the Transient Response of UAV Rotors”, 14th Annual International Micro Air Vehicle Conference and Competition, Aachen, Germany, 2023
- Al-Zubaidi, S., Stol, K. “Preliminary design optimisation of a novel fixed-tilt heterogeneous UAV for horizontal agility”, 2022 International Conference on Unmanned Aircraft Systems (ICUAS), 2022
- Al-zubaidi, S., Stol, K. “Design Optimisation of Fully Actuated UAVs Using Hybrid Optimisation”, Journal of Intelligent & Robotic Systems, vol. 111, no. 1, pp. 1–21, 2025.
Dexterity assessment of over-actuated drones
Masters Research
Chantelle Singh. Supervisor: Karl Stol
Aerial manipulation is the ability to interact with the environment using a UAV. This is typically achieved using a tool or an aerial manipulator. An important characteristic in whether manipulation is successful is dexterity. There is yet to be a standardized way to assess the dexterity of UAVs.
This project will focus on developing a standardized dexterity assessment consisting of several tests to determine how dexterous an over-actuated UAV is. It will be such that it is easily replicated and can be used on a range of UAVs.
Related:
Fully-Actuated Pen-Drone
BE(Hons) Research Project
Elise Oxenham & Henry Guo. Supervisor: Karl Stol
One challenge with UAVs is the ability to precisely maintain a steady contact with a surface while it is in flight. Having this capability would prove to be immensely useful in numerous applications, such as infrastructure inspection of towers or bridges, which are not easily accessible by humans.
This project aims to experiment with UAV interaction with a stationary surface, through design and use of an aerial manipulator and control of the drone system. The desired result of this research is to demonstrate the functionality of this system by having the UAV draw on a whiteboard.
Incorporation of a Force sensor in Fully Actuated UAV and Control Design
BE(Hons) Research Project
Agustin Soto & Oliver Vannoort. Supervisor: Shahab Kazemi
Measuring forces is essential for a multi-rotor UAV to interact with the environment. Various methods exist for force measurement, including using springs to gauge deflection, employing an Inertial Measurement Unit (IMU) for force estimation, or direct use of a force sensor. Force measurement is particularly crucial for applications requiring controlled force exertion.
This project focuses on integrating a force sensor into a rigid attachment a fully-actuated UAV. The aim is provide online force feedback to be incorporated into the flight controller in order to achieve consistent flight and stable contact with the environment.
Related:
Variable Arm Angle and Control Modification for Multirotor UAVs
BE(Hons) Research Project
James Blackhurst & Oliver Reedy. Supervisor: Shahab Kazemi
Recent innovations in drone research has involved adding fixed arms for physical interaction. The introduction of rotating arms may play a pivotal role in potential physical interaction applications.
This project aims to develop and build a rotating arm attached to a fully actuated UAV. The
drones controller and its gain will be modified to maintain stability and accuracy when the arm rotated around the drones axis. The drone control will also be designed to maintain performance when in physical contact with an object. The real-time angle of the arm will affect the control gains to maintain stability during free flight and contact.
Related:
Fully-Actuated Screwdriving Unmanned Aerial Vehicle
BE(Hons) Research Project
Louis Lee & Dulina Senevirathna. Supervisor: Karl Stol
Advancements in Aerial Manipulation research are continuously expanding the potential of drones to assist humans in the remote execution of dangerous tasks, thereby minimising risk to human life. Researchers have directed particular focus towards aerial manipulation tasks such as grasping, fetching, writing, peg-in-hole insertion, and vertical drilling into the ground. However, manipulation tasks involving horizontal screwdriving onto vertical surfaces remain relatively unexplored, yet are critical and prevalent in the engineering and construction sectors. We will be investigating the feasibility and implementation of such an operation on a fully-actuated UAV. We will also be developing a novel screwdriving actuator attachment for such a UAV to overcome challenges and achieve requirements associated with performing a screwdriving operation in the air, and perform tests to analyse and quantify its performance.
This research delves into the design of a novel lightweight screwdriving actuator for performing remote horizontal screwdriving operations using a fully-actuated UAV.
Related:
Cooperative Aerial Manipulation
BE(Hons) Research Project
Jaap Skinner & Connor Williams. Supervisor: Karl Stol
Payload control and precise positioning have become increasingly essential in various industries. Industries such as construction, agriculture, and many more often require the ability to position and orient payloads with unique geometries. Utilising a swarm of drones to perform these tasks presents a ground-breaking solution by allowing the payload-carrying capacity to be scaled using multiple drones while achieving high precision and control.
Traditional methods, such as cranes or helicopters, are often impractical due to their cost, lack of precision, excessive resource use (e.g., crane setup and pack down, helicopter flight from and to landing pad) and limited suitability for carrying payloads with unique geometries. The versatility and flexibility of a multi-drone system could provide a cost-effective and efficient alternative. This project explores the potential use of multi-drone systems to position and accurately orient objects with various geometries.
Performance of Variable Pitch Propellers in Wind
BE(Hons) Research Project
Ruby Chen & Alex Zhao. Supervisor: Nicholas Kay
Multirotor drones usually employ fixed-pitch propellers as their main means of flying. Simple, lightweight and reliable, these propellers suffer aerodynamically when used outside of their expected operational point. Furthermore, the system response is limited by the inertia of the motor-propeller combination, as force changes can only be made through changing the motor speed.
Variable Pitch offers a solution to this problem, being able to adapt to the incident wind and desired loading, while providing a faster change in force output. Used on helicopters and conventional aircraft, the aerodynamic loads of variable-pitch propellers and their transient response has not yet been studied for drone-sized aircraft.
This project will experimentally assess the steady and transient forces produced by a variable-pitch propeller in the presence of wind. This work will be conducted in the Boundary Layer Wind Tunnel, building on from prior research in the Drone Technology Research Group.
Related:
Transient Loads on a UAV in Turbulent Cross Flows
BE(Hons) Research Project
Hugh Holroyd & Doug Russ. Supervisor: Nicholas Kay
If you have flown into Wellington, you know about crossflows and windshear: that sudden gust catching the side of the aircraft, causing a discomforting jump for passengers. Now imagine that the aircraft is much, much smaller, and the gusts more frequent. This is the scenario facing small Uninhabited Aerial Vehicles (UAVs), which often operate low to the ground and are envisaged as a future means of urban delivery or traffic monitoring. It is critical that we understand the operational limits of these aircraft, to ensure safe and successful operations. Traditional wind tunnel tests are taken with the aircraft facing into the flow, with steady wind conditions. However, this is not representative of the environment experienced by small UAVs.
One such UAV is Kahu, a fixed-wing aircraft with a wingspan of 2.3 m. Using the Boundary Layer Wind Tunnel, you will conduct tests to record the forces and moments acting on the aircraft with various crosswinds, replicating the conditions expected in urban flight. This will be used to determine the sensitivity of the aircraft to crosswinds, and define operational limitations for safe flight in urban conditions.