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Design, implement and verify in vitro the control firmware of a neurostimulator that elicits localized neuronal responses for a thalamic visual prosthesis.
Posted on by Pablo Sarabia Ortiz
Design, implement and verify in vitro the control firmware of a neurostimulator that elicits localized neuronal responses for a thalamic visual prosthesis

Introduction

Achieving precise and localized neuronal stimulation is one of the main challenges in neurotechnology. Current approaches often suffer from low spatial specificity, which can lead to unintended activation of surrounding tissue and reduced therapeutic efficiency. A method capable of eliciting spatially localized responses would represent a significant advancement, allowing more targeted interventions, minimizing side effects, and enabling the development of high-resolution neuroprosthetic systems.

Keywords

Brain-Computer Interface (BCI), Visual prosthesis, Lateral geniculate nucleus (LGN),
Neurostimulator, Beamforming, Temporal Interference Stimulation (TIS), Deep brain stimulation
(DBS), Firmware, Neurotechnology, In vitro.

Objective

The objective of this master’s thesis is to design, implement, and verify in vitro the control firmware for a neurostimulator capable of producing localized neuronal responses. This work is framed within the VISNE project, which seeks to advance thalamic visual prostheses. The strategy explored combines two advanced stimulation techniques: beamforming and temporal interference stimulation (TIS), both aimed at improving spatial precision and overcoming the low specificity of conventional neurostimulation.

Electrode Setup for In Vitro Measurement

Testing Electrode Setup

Solution

Experimental Setup for electrode stimulation tests
The experimental setup for in vitro verification

To achieve this, a programmable four-channel neurostimulator was used. The device can generate multiple synchronized waveforms, including biphasic and sinusoidal signals, enabling the shaping of the electric field inside neural tissue. First, computational simulations of beamforming and TIS were performed to predict how stimulation patterns could be steered toward specific regions. Then, in vitro experiments were conducted using the neurostimulator and a custom experimental setup to validate these methods.

Results

The results showed strong spatial correlations between simulations and experimental measurements, confirming that both beamforming and TIS can focus electrical stimulation effectively. However, challenges were found in reproducing field amplitudes with high accuracy, as statistical analyses (MAE, RMSE) revealed residual errors in the measurements. Among the two techniques, TIS proved particularly promising, successfully generating low-frequency interference envelopes with strong spatial selectivity.

Temporal Interference results comparison with simulation

Design and Implementation of a Device for Capturing Biological Signals Applied to the Treatment of Ischemic Stroke.
Posted on by rookie
Ikki PCB design

Introduction

This work is part of the STRIKE project, a multidisciplinary initiative aimed at developing new therapeutic strategies for the treatment of ischemic stroke, one of the leading causes of death and disability in Spain and worldwide. STRIKE integrates three techniques: transcranial magnetic stimulation (TMS), implantation of mesenchymal stem cells encapsulated in silk fibroin, and electrical stimulation of the auricular branch of the vagus nerve (aVNS).

In this context, the Ikki device has been designed and implemented a portable system for acquiring biological signals, specifically electrocardiogram (ECG) in rodents and electroencephalogram (EEG) in humans. This work primarily focuses on the electrical stimulation of the auricular branch of the vagus nerve, although it is partially related to transcranial magnetic stimulation. The main goal is to enable real-time monitoring of physiological responses to the applied therapies, thereby facilitating personalized treatment and experimental validation of the proposed techniques. The device has been validated in a real-world setting through human trials.

Keywords

Electrocardiogram, electroencephalogram, biological signals, electrophysiology, biomedical
device, portable, low power consumption, vagus nerve, ischemic stroke, treatment, embedded
system.

The problem

Clinical Context

Ischemic stroke accounts for more than 80% of stroke cases. Conventional treatment is based on early reperfusion and physical rehabilitation, but neurological recovery remains limited. Therefore, new strategies are needed to complement current treatments and improve neuroprotection and brain regeneration. The STRIKE project was born from the development of these new strategies.

Technological Need

To experimentally validate the techniques proposed in the STRIKE project, it is essential to have a device capable of accurately acquiring physiological signals in a portable, non-invasive, and user-friendly manner for researchers. ECG and EEG signals allow for the evaluation of the impact of therapies on the nervous and cardiovascular systems and are fundamental for establishing a personalized treatment approach.

CTB ADC and stimulator

Acquisition system for ECG and stimulation used in the CTB.

Currently, experiments conducted at the Center for Biomedical Technology (CTB) use very large devices that hinder researchers due to their size. Therefore, the long-term goal is to develop a device with a “closed-loop approach.” To achieve this, the signal acquisition device is developed first, and later stimulation will be integrated into the same device.

Proposed Solution

The Ikki device has been developed as a comprehensive solution for acquiring and transmitting biological signals in the context of ischemic stroke treatment. Its design meets criteria of portability, low energy consumption, data capture precision, and ease of use in experimental and clinical environments. The system has been divided into hardware and software components.

Hardware Development (HW)

Ikki PCB design
Ikki V1.3

The complete hardware system has been built around a custom board integrating the following modules:

  • MSP430FG479 Microcontroller: Responsible for acquiring signals from the acquisition circuits. It includes built-in SD16-type ADCs. This is the main microcontroller of the entire system.
  • Signal Acquisition Circuits: Composed of several modules that allow analog processing of the signals to be captured, with filtering and amplification adapted to each signal type.
  • Power Supply System: Composed of a PMIC, a linear regulator, and an inverter that enable symmetrical power supply to the entire system.
  • Communications: Includes test points that allow data collection through the main microcontroller.
  • Connectors and Electrodes: Adapted for use in humans and rodents, ensuring secure and stable connections during acquisition.

The design has gone through several iterations, from initial prototypes to the final version Ikki V1.3, optimized for real-world testing. The quality of the acquired signals has been validated through comparisons with commercial systems.

Software Development(SW)

The software is divided into four layers:

  1. Acquisition Layer:
    • Developed in C using Code Composer Studio.
    • Programs the main microcontroller MSP430FG479.
    • Acquires data via the microcontroller’s built-in ADCs, processed through the acquisition circuits.
    • These data are then sent in a predefined format via SPI or UART to the bridge layer.
  2. Communication layer:
    • Defines a state machine to differentiate data acquired from various channels by the main microcontroller.
  3. Bridge layer:
    • Programs an ESP32 using ArduinoIDE.
    • Receives data from the acquisition layer via SPI/UART and forwards them via BLE.
    • Enables wireless functionality of the device.
  4. Visualization layer:
    • Programmed in Python.
    • Establishes a connection with the bridge layer and displays the data received via BLE on a device screen, such as a laptop.

Oferta de becas Cátedra Verisure 2025-2026
Posted on by araujo

Empezamos el curso con fuerza! Un curso más, dentro de las actividades de la Cátedra Verisure se contempla el establecimiento de un programa de becas en áreas de interés para la empresa y que complementen el proceso formativo de l@s estudiantes.

Por lo tanto, se lanza esta convocatoria de becas para el presente curso académico hasta completar las plazas.

Duración: 9 meses

Dedicación: 4 horas/día

Remuneración: 500 € / mes

Posibilidad de realizar el Trabajo Fin de Máster, Trabajo Fin de Grado y prácticas en empresas.

Interesad@s enviar un correo electrónico con el Curriculum Vitae y los temas de las becas a los que quiere optar (por orden de prioridad) indicando en el asunto [Becas Cátedra Verisure] a la siguiente dirección:

araujo@b105.upm.es

Estaremos recibiendo vuestras solicitudes hasta el 30 de Septiembre y empezaremos el 6 de Octubre. Toda la información sobre la temática de las becas aquí:

orferta_becas_CV_2526

TFG: development of a data model for the detection of presence of people in domestic enviroments
Posted on by rookie

This project aims to develop a presence detection model for domestic environments equipped
with IoT-based security systems. The model is based on the integration and analysis of data
provided by various Securitas Direct – Verisure devices, such as magnetic door and window
sensors, infrared-equipped cameras, and emerging technologies like WiFi Sensing.


Currently, the company has devices that collect real-time information, but it lacks a system
that combines this data to accurately detect human presence. The proposed model aggregates
all available data and determines whether there is presence in the environment based on
logical rules.


The work includes a preliminary study of Verisure’s technology and the state of the art, the
design, development, and deployment of the model, the preparation of a simulation
environment, the collection and processing of real data, and the analysis of results. Finally,
potential future developments, applications, and uses of the model are evaluated, along with
the ethical, social, economic, and environmental impacts of the project.
The project has been carried out within the Securitas Direct – Verisure research chair,
following a SCRUM methodology for its development.

The system integrated the following components:

Central Unit (CU)

Magnetic door and window sensors

Photodetector cameras equipped with PIR sensors and WiFi Sensing

Keypad

Remote keyfob

The final method consisted of a lightweight rule-based model developed in Python, embedded directly in the Central Unit. This model integrates data from the different sensors and WiFi Sensing, applying weighted logic and a sigmoid output function to generate a real-time confidence percentage of human presence.

Several visual interfaces were created to controll the model parameters, create simulated scenarios, or visualize the output of the model. The most relevant of these was developed to visualize the recorded data and model predictions. This interface displays the data collected from all sensors and the acumulated weight over time, which is reset whenever the front door is opened, as well as the correspondence between the model predictions and the actual presence of people.

The solution was validated both in simulation and with real data collected at the Cátedra Securitas Direct. The results demonstrated that the model accurately distinguished between presence and absence across different usage scenarios, such as entering, leaving, or moving inside the home. After refining corner cases, the system achieved an accuracy of approximately 86%, while maintaining very low resource usage (<3% RAM and <1% CPU).

This work provides a reliable presence detection model that strengthens the Verisure security ecosystem without additional hardware costs, preserves user privacy, and ensures efficient performance.

This project was carried out by Jorge Alejandro Estefanía Hidalgo and supervised by Belén Vega Castrillo.

Mesa redonda – Modificación de conductas como apoyo a las operaciones
Posted on by Octavio Nieto-Taladriz

Academia de las Ciencias y las Artes Militares – Sección de Prospectiva Tecnológica

El pasado 7 de mayo tuvo lugar una mesa redonda en la Academia de las Ciencias y las Artes Militares (ACAMI) organizada por nuestro compañero Octavio Nieto-Taladriz, de la que es Académico. Además de tener un formato presencial, la mesa redonda se retransmitió y el vídeo puede verse en el siguiente link.

Resumen

En la actualidad las operaciones multidominio están teniendo un fuerte auge, un gran impacto en las nuevas operaciones y hay una gran preocupación sobre cómo abordarlas, tanto bajo el punto de vista ofensivo como defensivo. Por otra parte, la sección de Prospectiva Tecnológica de la ACAMI pretende con esta mesa redonda sembrar la semilla de cual podría ser un aspecto futuro de especial relevancia como es el poder modelar el comportamiento humano y con ese conocimiento ser capaces de crear estrategias tanto de ataque como de defensa.

Con la amplia extensión de las redes sociales y su capacidad de influencias en los individuos se abre un nuevo mundo de modificación de conductas, como todos podemos ver está ocurriendo en los últimos años. Por otra parte, la existencia de herramientas de procesado de datos a gran escala y la realización de operaciones de inteligencia y control sobre ellos pueden permitir la elaboración de estrategias complejas de modificación de conductas individuales dentro de un colectivo. Un paso relevante es el paso desde la influencia sobre masas a la influencia dirigida y personalizada de elementos clave previamente definidos como críticos para una estrategia de acción.

Finalmente, hay un campo en el mundo de la psicología que tiene puntos en común con la radicalización de un individuo de especial interés para la creación de los diferentes relatos e informaciones a inyectar. Asimismo, y para la parte defensiva, el mundo de la psicología tiene mucho que aplicar para que puedan identificarse ataques como el planteado y poder tomar medidas preventivas. El concepto de “Guardaespaldas Virtual” toma sentido en un entorno como el que se plantea como forma de protección de los individuos frente a este tipo de ataques.

En esta mesa redonda se plantearán conceptos sobre este tema como punto de discusión para el posible desarrollo de estrategias y herramientas tanto ofensivas como defensivas en este campo de influencia sobre individuos.

Datos de la mesa redonda

Fecha: 7 de mayo – Hora: de 18:00 a 20:00 horas – Lugar: Sede de ACAMI

18:00 Palabras de bienvenida

GE R. D. Jaime Domínguez Buj – Presidente de la Academia de las Ciencias y las Artes Militares

18:10  Ponencia “La desinformación un instrumento clave en los conflictos actuales”

GB R. Dr. Miguel Ángel Ballesteros Martín – ACAMI

18:30   Ponencia “Así somos, así nos influyen”

Comandante Psicólogo Dña. Lucía Pery Pardo De Donlebún – EMAD

18:50 Ponencia “Caso práctico: Poniendo los huevos en la cesta”

Prof. Dr. Octavio Nieto-Taladriz García – Catedrático de Universidad en el Departamento de Ingeniería Electrónica de la E.T.S.I. de Telecomunicación – Universidad Politécnica de Madrid 

Prof. Dr. María Paz García Vera – Catedrática de Psicología Clínica en el Departamento de Personalidad, Evaluación y Psicología Clínica – Universidad Complutense de Madrid

19:30 PREGUNTAS

20:00 CLAUSURA