GENERAL INFORMATION 
---------------------------
1. Dataset title:
Adding Proximity Sensing Capability to a Tactile Array Based on Off‑the‑Shelf FSR and PSoC (Dataset)

2. Authors:
Castellanos-Ramos, Julián; Trujillo-León, Andrés; Navas-González, Rafael; Barbero-Recio, Francisco; Sánchez-Durán, José Antonio; Oballe-Peinado, Óscar; Vidal-Verdú, Fernando

3. Author contact information: 
Castellanos-Ramos, Julián (jcramos@uma.es)

METHODOLOGICAL INFORMATION 
---------------------------
This dataset contains the data obtained from the experiments described in the article:
J. Castellanos‑Ramos et al., “Adding Proximity Sensing Capability to a Tactile Array Based on Off‑the‑Shelf FSR and PSoC,” IEEE Transactions on Instrumentation and Measurement, vol. 69, no. 7, pp. 4238–4250, July 2020. 
DOI: 10.1109/TIM.2019.2944555
URI: https://hdl.handle.net/10630/32690
URL: https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=8853265&isnumber=9112796

Abstract: Tactile sensors have been incorporated into robots to help in many tasks, such as preventing damage to humans in collaborative works or assistance or in dexterous manipulation. Proximity sensors are also common in robotics and are proposed to implement pretouch in multimodal realizations. Many tactile sensors are based on off-the-shelf force-sensing resistors (FSRs). The parasitic capacitance associated with the electrodes of the FSR can be exploited to measure proximity. Moreover, it is possible to implement both force and proximity signal acquisition with a single chip. This article presents a multimodal proximity and tactile patch based on commercial FSR plus a programmable system on chip (PSoC). The ability to measure proximity is achieved without adding any extra element. Discussions about key design issues as well as results that show the performance of the sensor patch are presented. As proximity sensing array, the range is in the order of the size of the electrodes, and it depends on the properties of the object nearby, as expected. The best performance is observed for conductive objects. Therefore, this approach is especially interesting in human-robot interaction tasks, such as shaping robotic hands or grippers around the human body. Furthermore, dielectric objects are also detected, so it can also be used to implement pretouch in manipulation tasks. 

Keywords: Robot sensing systems;Force;Electrodes;Sensor phenomena and characterization;Optical sensors;Multimodal sensors;pretouch;programmable system on chip (PSoC);proximity sensors;tactile sensors

The dataset consists of two types of information:
1.- Finite element simulation files with the simulation model ready to run and obtain results.
2.- Data files in txt, xlsx, and csv formats, with data obtained from the experiments. 

FILE OVERVIEW 
---------------------------
The experimental data are organized into the following folders:
1.- FEA_Simulations; Finite element analysis model files.
2.- Measurements; Experimental measurements of the system:
2.a.- EMI; Tests evaluating the influence of electromagnetic noise.
2.b.- Force; Tests characterizing the response to applied force.
2.c.- Proximity; Tests evaluating the response to non‑contact approaching objects.
2.d.- Proximity and Force; Combined tests in which objects first approach and then make contact to apply force.
2.e.- Videos; Recordings showing the sensor response to approaching objects.

DATA-SPECIFIC INFORMATION:
---------------------------
1.-Finite Elements Analysis Simulations (FEA):
The simulation files do not contain the results due to file space limitations. To obtain the solutions, you must run the simulation in COMSOL Multiphysics version 6.3 or later.
* Used for creating Figure 3 (10.1109/TIM.2019.2944555):
- FSR-GND2_plano-Air-distance_bar0V-T25V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is grounded.
Terminal T2 is connected to 5 V.
- FSR-GND2_plano-Air-distance_bar0V-T2float.mph 
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is grounded.
Terminal T2 is floating.
- FSR-GND2_plano-Air-distance_bar0V-T20V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is grounded.
Terminal T2 is grounded.
- FSR-GND2_plano-Air-distance_barfloat-T25V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is floating.
Terminal T2 is connected to 5 V.
- FSR-GND2_plano-Air-distance_barfloat-T2float.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is floating.
Terminal T2 is floating.
- FSR-GND2_plano-Air-distance_barfloat-T20V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of the metallic prism (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The metallic prism is floating.
Terminal T2 is grounded.
* Used for creating Figure 4 (10.1109/TIM.2019.2944555):
- Celec-GND2_plano-Air-distance_barDielec80.mph
The sensor electrode is the only circular electrode, with the same diameter as FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The non-conductive object has εr = 80
- Celec-GND2_plano-Air-distance_barDielec3.mph
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The conductive object has εr = 3
- FSR-GND2_plano-Air-distance_barDielec3-T25V.mph 
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The non-conductive object has εr = 3
Terminal T2 is connected to 5 V.
- FSR-GND2_plano-Air-distance_barDielec80-T25V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The non-conductive object has εr = 80
Terminal T2 is connected to 5 V.
* Used for creating Figure 5 (10.1109/TIM.2019.2944555):
- FSR-GND2_plano-Air-distance_barDielec3-T25V.mph 
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The object has εr = 3
Terminal T2 is connected to 5 V.
- FSR-GND2_plano-Air-distance_barDielec12-T25V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The object has εr = 12
Terminal T2 is connected to 5 V.
- FSR-GND2_plano-Air-distance_barDielec80-T25V.mph
The sensor electrode is a Force Sensing Resistor (FSR) from Interlink, model FSR 402.
Parametric simulation with the distance in mm of a non-conductive object (0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, and 10 mm).
The object has εr = 80
Terminal T2 is connected to 5 V.

2.a.- Electromagnetic interference (EMI) dataset:
*Equipment Used:
Rohde & Schwarz Signal Generator, Model SML03
*Antenna Used:
Quarter-wave monopole tuned to 400 MHz, 50 Ω
*Equipment Settings:
Frequency sweep from 1 MHz to 500 MHz, Power: 11 dBm
Frequency sweep from 500 MHz to 3 GHz, Power: 15 dBm
*Test Procedure:
Three measurement cycles without RF interference:
1. Starting at 10 mm, the piece is moved to 0 mm.
2. Wait for 1 minute.
3. The piece is returned to its initial position (10 mm).
Data are collected in the files:
- NoBaseline_sinruido_1.xlsx
- NoBaseline_sinruido_2.xlsx
- NoBaseline_sinruido_3.xlsx
One measurement cycle with fixed interference at 100 kHz and 11 dBm:
1. Starting at 10 mm, the piece is moved to 0 mm.
2. Wait for 1 minute.
3. The piece is returned to its initial position (10 mm).
Data are collected in the file:
- NoBaseline_ruido100K.xlsx
One measurement cycle with an interference signal sweep from 1 MHz to 500 MHz:
1. Starting at 10 mm, the piece is moved to 0 mm.
2. Wait for 1 minute.
3. The piece is returned to its initial position (10 mm).
Data are collected in the file:
- NoBaseline_ruido_sweep1M-500M_1.xlsx
One measurement cycle with interference signal sweep from 500 MHz to 3 GHz:
1. Starting at 10 mm, the piece is moved to 0 mm.
2. Wait for 1 minute.
3. The piece is returned to its initial position (10 mm).
Data are collected in the file:
-NoBaseline_ruido_sweep500M-3G_1.xlsx

In cycles where noise is applied, the antenna tip is positioned approximately 3 cm from the studied taxel. From each cycle, a 50-second window (within the central 1-minute waiting period) is extracted, and the average digital value of the studied taxel (taxel 2) and its standard deviation (std) are calculated. The results are collected and summarized in the file:
- Results_EMI

2.b.-Force dataset:
* Dataset used for figure 11(b) (10.1109/TIM.2019.2944555):
Force measurements exerted by an aluminum prism on the sensor (taxel number 2) with an elastomer (range from 0 to 10N):
- Resultado-SinFiltro-Tactel-ElasRojo2mm_AA_SwSinUmbral_F_F2_1.csv 
  …
- Resultado-SinFiltro-Tactel-ElasRojo2mm_AA_SwSinUmbral_F_F2_30.csv

Data, from taxel number 2, are extracted and analyzed in the file:
- Resultado-SinFiltro-Tactel-ElasRojo2mm_AA_SwSinUmbral_F_F2.xlsx
The range of exerted force is indicated in the file:
- Resultado-SinFiltro-Tactel-ElasRojo2mm_AA_SwSinUmbral_F_F2.txt

2.c.-Proximity dataset:
* Dataset used for figure 11(a) (10.1109/TIM.2019.2944555):
Proximity measurements of an aluminum prism at different heights with respect to the sensor surface (0 mm to 7 mm):
- Resultado_P_F8_mm0.csv
  …
- Resultado_P_F8_mm7.csv
Proximity measurements of an aluminum prism at different heights with respect to the sensor surface and an elastomer on it (0 mm to 7 mm):
- Resultado-Tactel-ElasRojo2mm_AA_P_F8_mm0.csv
  …
- Resultado-Tactel-ElasRojo2mm_AA_P_F8_mm7.csv
Data, from taxel number 8, are extracted and analyzed in the file:
- Resultado_P_F8vsElas_AA_P_F8.xlsx

* Dataset used for figure 12 (10.1109/TIM.2019.2944555):
Proximity measurements of an aluminum prism (conductive object) at different heights with respect to the sensor surface and an elastomer on it (0 mm to 7 mm), for taxels 1, 2, 4, 7, 8, 11 and 13:
- Resultado-Tactel-ElasRojo2mm_P_F1_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F1_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F2_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F2_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F4_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F4_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F7_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F7_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F8_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F8_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F11_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F11_5.csv
- Resultado-Tactel-ElasRojo2mm_P_F13_1.csv
  …
- Resultado-Tactel-ElasRojo2mm_P_F13_5.csv
Data are extracted and analyzed in the files:
- Resultado-Tactel-ElasRojo2mm_P.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F1.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F2.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F4.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F7.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F8.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F11.xlsx
- Resultado-Tactel-ElasRojo2mm_P_F13.xlsx

* Dataset used for figure 13 (10.1109/TIM.2019.2944555):
Proximity measurements of an aluminum prism (conductive object) versus a plastic one (non-conductive object) at different heights with respect to the sensor surface (0 mm to 7 mm):
Conductive object:
- Resultado_NoConduc_P_F1_1.csv
  …
- Resultado_NoConduc_P_F1_10.csv
Non-conductive object:
- Resultado_P_F2_1.csv
  …
- Resultado_P_F2_5.csv
Data are extracted and analyzed in the file:
- Resultado_NoConduc_P_F1vsResultado_P_F2.xlsx

2.d.-Force plus proximity dataset:
* Dataset used for figure 11(c) (10.1109/TIM.2019.2944555):
Recording of data when a metal object approaches the sensor (taxel number 1), comes into contact with it, exerts force on it, and returns to its original position following the reverse sequence:
- Resultado-Tactel-ElasRojo2mm_F&P_F1_2.csv
Data, from taxel number 1, are extracted and analyzed in the file:
- Resultado-Tactel-ElasRojo2mm_F&P_F1_2.xlsx

2.e.- Videos
Recorded videos showing the system's output when an arm dressed in clothing approaches the sensor and when a finger follows a path toward several of the sensor's taxels, Fig_14-arm_clothing.mp4 and Fig_15-finger_route.mp4 respectively.