Thesis Projects Proposals

Dual-Arm Force Control for Peg-in-Hole Assembly

The project’s aim is to employ a dual-arm setup for the accomplishment of a peg-in-hole task. Peg-in-hole is a type of assembly task in which a convex object (peg) has to be plugged into its concave counterpart (hole) of the same shape. The main idea is to deal with two serial robots, each one of them assigned with a precise job: while the first robot holds the hole in position, the second robot, which is force-controlled, has to insert the peg. The feedback received from the sensor attached to the second-robot end-effector is used to adjust the motion in order to facilitate the insertion of the peg.

In collaboration with: DIN

Time-Optimal Trajectory Planning for Manipulation of Loosely-Placed Objects: the Waiter Motion

The project aims at solving the so-called general waiter problem. The waiter problem consists of moving a tray (which is attached to the robot end-effector), on which some cups are placed. The motion must be executed by the robot in the fastest way possible, from one pose to another, such that the cups do not slide at any time. The geometric path of the tray is prescribed, whereas its orientation represents a variable of the problem.

In collaboration with: DIN

Study of rectilinear motion-to-motion anti-sloshing trajectories

The term sloshing refers to the stirring of a liquid inside a container during its motion. Anti-sloshing motion laws are studied in the literature to avoid liquid spillage and, in general, control the motion of the liquid free-surface. Classical anti-sloshing methods are applied to execute rest-to-rest movements. This project aims to develop rectilinear anti-sloshing trajectories for an utterly general situation: from a motion condition (velocity and acceleration different from zero) to a motion condition.

In collaboration with: DIN

Development of anti-sloshing paths for 2D planar motions

The term sloshing refers to the stirring of a liquid inside a container during its motion. Anti-sloshing motion laws are studied in the literature to avoid liquid spillage and, in general, control the motion of the liquid free-surface. This project aims to develop a general method for the fast computation of 2D planar anti-sloshing motions by controlling only the geometrical path of the container without optimizing the timing law.

In collaboration with: DIN

Modeling and design of dynamic balancing systems for serial robots

Robots are commonly used in many industrial applications, especially in the packaging industry, where repetitive operations must be performed in the shortest time to saturate the required productivity. It is essential to reduce the weights and inertia of the moving parts of the manipulators to perform this task. With this in mind, the first aim of this work is to analyse the existing robot architectures developed by Marchesini Group S.p.a. and to evaluate the possibility of not mounting dynamic balancing systems (springs, pneumatic cylinders, …) on these robots (that is beneficial in the execution of highly dynamic tasks). The second objective is to develop an instrument to guide the mechanical designer in choosing the balancing systems (where necessary) by taking into account the inertia of the mobile parts, the motor power consumption, and cost analysis.

In collaboration with: Marchesini Group S.p.a.

IMU-based shape sensing of planar continuum parallel robots

Continuum robots (CRs) are manipulators usually made of slender flexible components, developed to respond to the increasing necessity of safe interactions between robots and the environment. CRs are well suited for applications where the stiffness of rigid-link robots is considered a disadvantage.  Continuum parallel robots (CPRs) have been proposed to mitigate the disadvantages typical of serial continuum robots such as their reduced payload capability. CPRs are commonly made by flexible beams disposed in a parallel arrangement, and connected to a rigid end effector. Despite the great effort dedicated to CRs accurate modelling, shape sensing techniques are at an early stage. Moreover, while IMUs are currently employed in serial CRs (mounted at the end effector, or in several intermediate sections) this topic remains unexplored in CPRs. In this project, we propose the application of IMUs for the reconstruction of the shape of a continuum parallel robot. IMUs will be placed on the beams, and, thanks to the obtained data, their shape could be reconstructed.

In collaboration with: DIN

Development of an industrial robot operating system

The project aims at the complete porting of a well-consolidated operating system for robot operation and control, developed in C++ and running on Linux, on industrial hardware and software. The software needs to be developed in Structured Text on a Beckhoff IPC, through Twincat software. Other than logic control, algebra libraries will have to be optimized for robot control. Experiments will be carried out to compare the performances of the previous operating system and the newly developed one.

In collaboration with: DIN

Study of an optimal design for large-scale additive manufacturing with a cable-driven parallel robot

Cable-driven parallel robots use cables instead of rigid links to move an operating tool in space. They are naturally well-suited for large-scale operations but are limited by cables only exerting unidirectional forces. Therefore, their architecture needs to be optimized depending on the desired operational space, and the expected loads that the tool exerts on the robot end-effector. This project aims at investigating optimal architectures for the operation of an extruder mounted on the robot platform. Depending on the project outcome and available founding, a prototype may be designed, manufactured, and tested on.

In collaboration with: DIN

Manipulation of large plates with Underactuated cable-driven parallel robots and electro-adhesive grippers

Cable-driven parallel robots use cables instead of rigid links to move an operating tool in space. They are underactuated when fewer cables than the end-effector degrees of freedom are used. On one hand, their workspace is highly accessible, on the other only the position of the end-effector can be precisely controlled. This project aims at developing a manipulation strategy leveraging underactuated robots’ intrinsic flexibility so that large plates can be grasped with an electro-adhesive gripper. To achieve this, the robot tool needs to be placed in contact with the object to be manipulated through a hybrid position-force control.

In collaboration with: DIN

Dynamic stability of rest-to-rest trajectory planners for underconstrained cable robot

Cable-driven parallel robots use cables instead of rigid links to move an operating tool in space. They are underactuated when fewer cables than the end-effector degrees of freedom are used. On one hand, their workspace is highly accessible, on the other, they maintain freedom even when actuators are locked. This means that trajectory planning must be carefully planned to reduce unwanted end-effector oscillations during and at the end of a trajectory. This project aims at investigating how fast the end-effector of the robot can move without incurring in dynamic instabilities (platform flip) if the operations are interrupted by an emergency stop. Project results will be validated through experiments.

In collaboration with: DIN

Integrazione hardware e software di un joystick per il telecontrollo di un robot collaborativo UR5e tramite socket TCP/IP

Hardware and software integration of a joystick for remote control of a UR5e collaborative robot via TCP/IP socket

Connecting a joystick to a PC is already possible to control a collaborative robot (or cobot) such as the model UR5e by Universal Robots at the disposal of IRMA L@B. However, previous work was developed and demonstrated how it is possible to connect a joystick directly to the cobot control box by bridging the two devices with a simple Arduino microprocessor. Nonetheless, the limited amount of digital and analog input exposed by the cobot controller does not allow the robotic arm to control all six axes at once. This project aims at solving this issue by adding an ethernet shield to the Arduino board so that the connection can migrate to the socket port of the controller. In this way, the Arduino+joystick system can act as a standard MODBUS module or a generic TCP/IP client to a suitable server run on the cobot controller.

In collaboration with: DIN

Studio di traiettorie anti-sloshing rettilinee basate su leggi di moto segmentate

Study of rectilinear anti-sloshing trajectories based on segmented motion laws

The term sloshing refers to the stirring of a liquid inside a container during its motion. Anti-sloshing motion laws are studied in the literature to avoid liquid spillage and, in general, control the motion of the liquid free-surface. This project aims to develop rectilinear anti-sloshing trajectories by simply choosing the duration of the segments in common segmented motion law (e.g. constant acceleration, trapezoid acceleration, …), instead of applying techniques based on a modification of a predefined trajectory (input shaping, IIR filtering, FIR filtering, …).

In collaboration with: DIN