Joan Canals

Control electronics integration toward endoscopic capsule robot performing legged locomotion and illumination

Miniaturization of sensors and actuators up to the point of active features in endoscopic capsules, such as locomotion or surgery, is a challenge. VECTOR endoscopic capsule has been designed to be the first endoscopic capsule with active locomotion. It is equipped with mini-legs driven by Brushless DC (BLDC) micro motors. In addition it can be also equipped with some other sensors and actuators, like a liquid lens, that permits to enable advanced functions. Those modules are managed by an ASIC specifically designed for the VECTOR capsule. The ASIC is a complete System-On-Chip (SoC) and integrates all the electronics needed to enable the legged locomotion and the sensing and actuating functions of the capsule in an unique chip. The SoC also enables other functions for endoscopic capsules such as drug delivery and a biopsy system. The size of the SoC is 5.1 mm × 5.2 mm in a 0.35 um high voltage CMOS technology.

An ultra low power IC for an autonomous mm 3 -sized microrobot

This paper is focused on the main issues of designing a SoC for a completely autonomous mm3-sized microrobot. It is described how all the electronics are included in a unique chip, the special requirements in the assembly process and how the hard constraints in power consumption are managed. Power in the robot is delivered by solar cells mounted on top and two supercapacitors which act as batteries. The maximum available energy for the SoC is 400 muW for driving the robot actuators and 1 mW for data processing. The special architecture of the SoC and power awareness are required to manage the very low available power.

Enabling multiple robotic functions in an endoscopic capsule for the entire gastrointestinal tract exploration

Commercial endoscopic capsules are passive. Nevertheless, active capabilities such as active locomotion, drug delivery or biopsy, among others, can now be offered with the aid of robotics. New robotic functions require additional electronics for control purposes, as well as for the sensors and actuators. To avoid increasing the capsule size as a consequence, it is useful to incorporate all the electronics into the minimum number of elements, preferably in a single ASIC. This paper describes the ASIC included in a robotised capsule with the abovementioned active functions. The ASIC is a system-on-chip (SoC) integrating all the electronics needed to control the other electronic elements in the capsule. It also enables the movement of two BLDC motors, illuminates the exploration region and focuses a liquid lens used to achieve advanced vision capabilities. Details of the complete system integration are also given.

An optically programmable SoC for an autonomous mm 3 -sized microrobot

A microrobot is a robot under a few cubic millimeters in size. Miniaturizing its components, power source, sensors and actuators, has proven challenging. As a consequence, few autonomous microrobots have been reported until recently [1–3]. These are simple mobile platforms, without sensors on board. Their electronics are basically focused on motion. I-SWARM is the first autonomous microrobot, 23mm3 and 70mg, designed to move, sense, take decisions, communicate and work in cooperation with other I-SWARM microrobots [4]. The area and weight of a microrobot are critical and limits the use of off-the-shelf components. So, it is required to integrate in a unique chip all the electronics, including the clock source, the POR and the voltage regulators.

A low cost fluorescence lifetime measurement system based on SPAD detectors and FPGA processing

This work presents a low cost fluorescence life time measurement system, aimed at carrying out fast diagnostic tests through label detection in a portable system so it can be used in a medical consultation, within a short time span. The system uses Time Correlated Single Photon Counting (TCSPC), measuring the arrival time of individual photons and building a histogram of those times, showing the fluorescence decay of the label which is characteristic of each fluorescent substance. The system is implemented using a Xilinx FPGA which controls the experiment and includes a Time to Digital Converter (TDC) to perform measurements with a resolution in the order of tenths of picoseconds. Also included are a laser diode and the driving electronics to generate short pulses as well as a HV-CMOS implemented Single Photon Avalanche Diode (SPAD) as a high gain sensor. The system is entirely configurable so it can easily be adapted to the target label molecule and measurement needs. The histogram is constructed within the FPGA and can then be read as convenient. Various performance parameters are also shown, as well as experimental measurements of a quantum dot fluorescence decay as a proof of concept.

Enabling swarm behavior in mm 3 -sized robots with specific designed integrated electronics

This paper presents a system on chip (SoC) designed specifically to control a mm3-sized microrobot called I-SWARM. The robot is intended to be part of a colony of 1000 members for studying swarm behavior in real time with real robots. The SoC offers a well-suited hardware platform to run multi-agent systems software. The SoC enables control of movement, communications and sensing. It is a platform where run multi-agent system software. With these capabilities, the robot is able for example to avoiding collisions, perform cooperative tasks, share information and, of course, solve different swarm scenarios and more complex tasks. The SoC has been fabricated with a 0.13 mum ultra low power CMOS process of STMicroelectronics and consumes less than 1.5 mW.

A SoC for studying multi-agent software/algorithms on a real swarm of mm3-sized microrobots

This paper presents a System On Chip (SoC) designed specifically to control a mm3- sized microrobot called I-SWARM. The robot is intended to be part of a colony of 1000 I-SWARM robots for studying swarm behavior in real time and in a real swarm. The SoC offers a well-suited hardware platform to run multi-agent systems software. It is composed of an 8051 microcontroller with 2 kB of data memory and 8 kB of program memory. The processor is provided with specific hardware modules for controlling the locomotion unit, the communications and the vibrating contact sensor of the robot. These modules perform basic tasks as movements or communications so the 8051 can focus on processing data and taking decisions. With these capabilities, the robot is able to avoiding collisions with other members of the swarm, performing cooperative tasks, sharing information and executing specialized tasks. The SoC has been fabricated with a 0.13 &mgr;m ultra low power CMOS process of STMicroelectronics and consumes less than 1 mW.

A low power IC to enable optical communications in a robotic swarm

In this paper a low power transceiver for short-range IR-communications between robots is described. The mm3- sized robots will be deployed in an arena of A4 sheet size with controlled illumination conditions. The transceiver can manage variations of background light from point to point in the arena, interferences induced by other robots and deals with the inter-robot distance, i.e., the amplitude of the signal to be detected.

A Portable Fluorescence Lifetime Spectroscopy Detector for Molecular Diagnosis

Fluorescence-based techniques are amongst the most widely used methods in molecular analysis in life science with multiple applications in clinical analysis and biomedical diagnosis. Considerable efforts have been directed toward the miniaturization of the fluorescence-based instruments, in an effort to reduce both cost and form factor for point of care (PoC) applications, but at the expense of increasing the complexity of the system or losing sensitivity. A new technology is being developed to build a PoC device based on fluorescence lifetime detection for molecular diagnosis with a sensitivity comparable to the bulky optical instruments and with a diagnosis time of a few seconds. Our PoC is a low-cost, simple, fast and easy to use general purpose platform, aimed at carrying out a fast diagnostics test through label detection of a variety of biomarkers. The system is designed to eliminate the optical requirements associated with traditional fluorescence lifetime instruments. With an array of ultra-sensitive detectors based on CMOS SAPD (single photo avalanche diode) technology along a custom microfluidic polydimethyl-siloxane (PDMS) cartridge on top of the sensor to insert the sample. The proximity of the sample and the SPAD sensor conjointly with the gate mode operation of the sensors, makes the use of lenses and optical filters unnecessary. The device is operated in Time Correlated Single Photon Counting (TCSPC), measuring the time of arrival of the photons after excitation of the fluorescence with a nanosecond laser diode. The sensor, which is extremely sensitive to light in the rage from 400 nm to 1000 nm, and of ultra-high speed, works in gated mode, which makes it practically unaffected by the intrinsic noise. The system has been characterized with several concentrations of fluorescent quantum dots (Qdot®605 streptavidin conjugate from Life Technologies) as proof-of-concept for lifetimes of several nanoseconds. The lifetime of the quantum dots is 35 ns, and is measured in only 15 s.

A 1 mW low power SoC for a mm 3 -sized microrobot

This paper is focused on the power features of a ultra-low power SoC for 3 times 3 times 3 mm3 microrobot. The SoC is based on the 8051 microcontroller and fabricated with a 0.13 mum ultra-low leakage CMOS process of STMicroelectronics. Because of the very restrictively power constraints, less than 1 mW, we have added a Power Management Unit (PMU) and a programmable clock generator to allow Dynamic Frequency Scaling (DFS). Leakage and analog static currents consume 700 muW leaving only 300 muW for robot driving and data processing. The static power has been improved by adding switch off transistors so the SoC can obtain more dynamic power by switching on/off different modules as a function of the task to execute.