Temperature and Humidity PID Controller for a Bioprinter Atmospheric Enclosure System

Abstract

Bioprinting is a complex process, highly dependent on bioink properties (materials and cells) and environmental conditions (mainly temperature, humidity and CO2 concentration) during the bioprinting process. To guarantee proper cellular viability and an accurate geometry, it is mandatory to control all these factors. Despite internal factors, such as printing pressures, temperatures or speeds, being well-controlled in actual bioprinters, there is a lack in the controlling of external parameters, such as room temperature or humidity. In this sense, the objective of this work is to control the temperature and humidity of a new, atmospheric enclosure system for bioprinting. The control has been carried out with a decoupled proportional integral derivative (PID) controller that was designed, simulated and experimentally tested in order to ensure the proper operation of all its components. Finally, the PID controller can stabilize the atmospheric enclosure system temperature in 311 s and the humidity in 65 s, with an average error of 1.89% and 1.30%, respectively. In this sense, the proposed atmospheric enclosure system can reach and maintain the proper temperature and humidity values during post-printing and provide a pre-incubation environment that promotes stability, integrity and cell viability of the 3D bioprinted structures.

Improving Cell Viability and Velocity in μ-Extrusion Bioprinting with a Novel Pre-Incubator Bioprinter and a Standard FDM 3D Printing Nozzle

“…The differences between this Atom Proton and the Prusa type 3D printer ( Figure 1 ) made the Atom Proton be the best choice to adapt a new extruder design and install it inside the pre-incubator. The design, components, construction and PID controller of the pre-incubator were detailed in a previous work [ 18 ] and shown in Figure 1 a,b.…”

“…Independently of the affordability of the bioprinter, some of them have enclosure systems capable of controlling the air flow through High Efficiency Particle Arresting (HEPA) filters, such as Cellink BioX ® (Cellink; Boston, MA, USA), Poietis ® (Poietis; Pessac, France) or 3D-Discovery BioFactory ® (REGENHU; Villaz-Saint-Pierre, Switzerland) [ 15 , 16 , 17 ]. As far as authors know, only Matamoros et al [ 18 ] have developed and tested an atmospheric enclosure (pre-incubator) capable of controlling the air flow as well as the inner temperature and humidity. Their system can be considered as a pre-incubator, preventing bioink to dry and cells to have better environment to increase their viability.…”

A low-cost and highly efficient method of reducing coolant leakage for direct metal printed injection mold with cooling channels using optimum heat treatment process procedures

“…The low-pressure injection molding process parameters involve injection pressure of 0.06 MPa and wax melting temperature of 99 °C. To evaluate the cooling performance of the injection mold with and without CCC, a system composed of a temperature controller [12] (JCM-33A, Shinko Inc.) and a thermo-electric cooler (TEC12706AJ, Caijia Inc.) and a temperature controller (JCM-33A, Shinko Inc.), and three k-type thermocouples [13] (C071009-079, Cheng Tay Inc.) was developed. Figure 9 shows the experimental setup for investigating the cooling performance of the injection mold with and without CCC.…”

Evaluation of the Reproducibility and Robustness of Extrusion-Based Bioprinting Processes Applying a Flow Sensor

“…When working with materials from natural sources, the batch-to-batch variance must be taken into account and also the filling level within the cartridge might require an extrusion pressure adaptation. In order to counteract these challenges, bioprinters are developed within an atmospheric enclosure system for controlling the environmental conditions such as temperature, humidity, and carbon dioxide concentration ( Matamoros et al, 2020 ). Such systems are certainly expensive and cannot react to material changes.…”