Testing Electroadhesion Forces

Description

The laboratory activity was carried out over a one-year period, from September 2022 to July 2023, at the RoboPhysics Laboratory of the Politecnico di Bari in collaboration with Ph.D. Massimiliano Mastrangelo, under the supervision of Prof. Vito Cacucciolo.

The goals of the work were to experimentally validate a contact analyitical model for electroadhesives (EA) on curved substrates (M. Mastrangelo et al., 2022, doi: 10.1109/RoboSoft54090.2022.9762116) and to realize, based on the model, a new innovative EA clutch using curved substrates. The advantages are amplifying curved clutch holding forces with respect to flat clutches with the same adhesion area and obtaining the same holding forces with lower voltages.

We tested electroadhesive tapes and clutches and mesaured the electroadhesion force when they adhere on curved or flat substrates.

We designed and realized a demonstration of a curved clutch: a longer EA tape was wrapped around a 3D printed support containing 6 cylinders coated with a substrate. Keeping the same applied voltage and same contact area of the clutch, we demonstrated that the curved clutch was able to hold more than 10 times the load held by a flat clutch. The curved clutch held a maximum load of more than 5 kg.

We mounted the clutch on a mannequin arm to show that it was able to hold loads hanging on the arm when the voltage is applied to the clutch. The arm held a maximum load of 1.25 kg.

My contribution

My contribution was:

• Improving the initial already-built setup solving some initial problems (live data aquisition using MATLAB, electromagnetic noise and vibration reduction, linear actuator control using Arduino).
• Validation of the setup with friction tests (linear actuator, load cell).
• Support to the experimental tests with EA tapes and EA clutches (linear actuator, load cell, high voltage power supply).
• Data analysis and plotting of the tests results with Matlab.
• Manufacture of the EA clutches: a layer of aluminum or conductive acrylic between two layers of polyimide.
• Support to the curved clutch demo tests.

Lego 390 - 1913 Cadillac

Description

This project was conducted with other two colleagues during the master's degree course of Virtual Prototyping in 2022 at the Polytechnic University of Bari. The goal of the work was to 3D model, using Autodesk Inventor, a real existing object. The model had to:

• Contain at least 5 different parts per each group member.
• Contain a mechanism inside (1 DOF).
• Contain at least one free form part.
• Improved with some modifications or new parts implementation.

It was chosen to model a LEGO 390 - 1913 Cadillac, that includes 210 modeled parts assembled all together with a bottom-up strategy. At the design stage, it was decided to implement the lego product with two side mirrors, modeling them as free form parts.

Common Lego bricks were modeled by creating an iPart of the 1x1 brick and parameterizing its dimensions in order to obtain all possible configurations of bricks useful for the project. All the remaining parts were modeled independently.

My contribution

My contribution was:

• Modeling the Lego bricks as iParts.
• Modeling the free form parts (side mirrors).
• Assembly of all the parts.
• Rendering pictures and videos using Inventor Studio.

Winding Machine

Description

This project was carried out at the RoboPhysics Laboratory of the Politecnico di Bari, under the supervision of Prof. Vito Cacucciolo.

A custom monofilament winding machine to manufacture fiber pumps was built in the RoboPhysics Laboratory of the Polytechnic University of Bari. The machine involves a linear actuator and 3D printed gears driven by a stepper motor. Both motors were controlled and synchronized using the Duet 3 Mini 5+ board. Other parts were 3D printed and anchored on the linear actuator to hange the filaments before starting the winding process. The machine is a replica of the one built in Smith et al., “Fiber pumps for wearable fluidic systems”, Science, vol. 379, no. 6639, pp. 1327–1332, Mar. 2023, doi: 10.1126/science.ade8654.

My contribution

My contribution was:

• Design and 3D print (FDM) of gears to allow the rotary motion of the winding guide.
• 3D print (FDM) of all the additional components.
• Machine assembly.
• Control and synchronization of the two stepper motors (Duet 3D, GCode)
• Winding process to fabricate fiber pumps.