This protocol describes the process of constructing an insect-machine hybrid system and carrying out wireless electrical stimulation of the flight muscles required to control the turning motion of a flying insect.
A ascensão de aparelhos eletrônicos digitais habilitados para rádio fez com que o uso de pequenos gravadores neuromusculares sem fio e estimuladores para estudar o comportamento de insetos em voo. Esta tecnologia permite o desenvolvimento de um sistema híbrido de inseto-máquina, utilizando uma plataforma de insetos vivendo descrito neste protocolo. Além disso, este protocolo apresenta a configuração do sistema e procedimentos experimentais de vôo livre para avaliar a função dos músculos do vôo em um inseto untethered. Para demonstração, alvo do músculo terceira axilar sclerite (3AX) para controlar e conseguir virar à esquerda ou à direita de um besouro voando. Um eléctrodo de fio de prata fina foi implantado no músculo 3ax em cada lado do besouro. Estes foram ligados às saídas de uma mochila sem fio (isto é, um estimulador eléctrico neuromuscular) montado no pronotum do besouro. O músculo foi estimulado em vôo livre, alternando o lado estimulação (esquerda ou direita) ou variando a stimulatiofrequência n. O besouro virado para o lado ipsilateral quando o músculo foi estimulado e exibiu uma resposta gradual para uma frequência cada vez maior. O processo de implantação e calibragem do volume do movimento sistema de câmera captura 3 dimensional precisa ser realizada com cuidado para evitar danos ao músculo e perder de vista o marcador, respectivamente. Este método é altamente benéfico para estudar vôo de insetos, uma vez que ajuda a revelar as funções do músculo do vôo de interesse em vôo livre.
An insect-machine hybrid system, often referred to as a cyborg insect or biobot, is the fusion of a living insect platform with a miniature mounted electronic device. The electronic device, which is wirelessly commanded by a remote user, outputs an electrical signal to electrically stimulate neuromuscular sites in the insect via implanted wire electrodes to induce user desired motor actions and behaviors. In the early stages of this research field, researchers were limited to conducting wireless recording of the muscular action of an insect, using simple analog circuits comprised of surface-mounted components1-3. The development of system-on-a-chip technology with radio frequency functionality enabled not only the wireless recording of neuromuscular signals but also the electrical stimulation of the neuromuscular sites in living insects. At present, a built-in radio microcontroller is small enough to be mounted on living insects without causing any obstructions to their locomotion4-13.
The development of the built-in radio microcontroller allows researchers to determine electrical stimulation protocols to induce desired motor actions to control the locomotion of the insect of interest. On the ground, researchers have demonstrated walking control by stimulating the neuromuscular sites of cockroaches4,12,14, spiders15, and beetles16,17. In the air, the initiation and cessation of flight were achieved using different methods such as the stimulation of the optic lobes (the massive neural cluster of a compound eye) in beetles7,9 and brain sub-regions in bees18, whereas turning control has been demonstrated by stimulating the antennae muscles and nervous system of the abdomens in moths11,19 and the flight muscles of beetles7,9,13. In most cases, a built-in radio microcontroller was integrated on a custom-designed printed circuit board to produce a miniature wireless stimulator (backpack), which was mounted on the insect of interest. This allows wireless electrical stimulation to be applied to a freely walking or flying insect. Such a microcontroller-mounted insect is what is referred to as an insect-machine hybrid system.
This study describes the experimental protocols for building an insect-machine hybrid system, wherein a living beetle is employed as the insect platform, and instructs on how to operate the robot and test its flight control systems. The third axillary sclerite (3Ax) muscle was chosen as the muscle of interest for electrical stimulation and demonstration of left or right turning control13. A pair of thin silver wire electrodes was implanted in both the left and right 3Ax muscles. Moreover, a backpack was mounted on the living beetle. The other ends of the wire electrode were connected to the output pins of the microcontroller. The backpack was small enough for the beetle to carry in flight. Thus, this allows an experimentalist to remotely stimulate the muscle of interest of an insect in free flight and investigate its reactions to the stimulations.
O processo de implantação é importante, pois afeta a confiabilidade do experimento. Os eléctrodos deve ser inserido dentro do músculo a uma profundidade de 3 mm ou menos, dependendo do tamanho do besouro (evitando o contacto com os músculos próximas). Se os eletrodos tocar os músculos próximos, ações motoras indesejáveis e comportamentos podem ocorrer devido à contração dos músculos próximos. Os dois eléctrodos deve ser bem alinhados para assegurar que não há curto-circuito ocorrer. Quando a fu…
The authors have nothing to disclose.
This material is based on the works supported by Nanyang Assistant Professorship (NAP, M4080740), Agency for Science, Technology and Research (A*STAR) Public Sector Research Funding (PSF, M4070190), A*STAR-JST (The Japan Science and Technology Agency) joint grant (M4070198), and Singapore Ministry of Education (MOE2013-T2-2-049). The authors would like to thank Mr. Roger Tan Kay Chia, Prof. Low Kin Huat, Mr. Poon Kee Chun, Mr. Chew Hock See, Mr. Lam Kim Kheong and Dr. Mao Shixin at School of MAE for their support in setting up and maintaining the research facilities. The authors thank Prof. Michel Maharbiz (U.C. Berkeley) his advice and discussion, Prof. Kris Pister and his group (U.C. Berkeley) for their support in providing the GINA used in this study.
Mecynorrhina torquata beetle | Kingdom of Beetle Taiwan | 10 g, 8 cm, pay load capacity is 30% of the body mass Aproval of importing and using by Agri-Food and Veterinary Authority of Singapore (AVA; HS code: 01069000, product code: ALV002). |
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Wireless backpack stimulator | Custom | TI CC2431 micocontroler The board is custom made based on the GINA board from Prof. Kris Pister’s lab. The layout of GINA board can be found at https://openwsn.atlassian.net/wiki/display/OW/GINA |
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Wii Remote control | Nintendo | Bluetooth remote control to send the command to the operator laptop | |
BeetleCommander v1.8 | Custom. Maharbiz group at UC Berkeley and Sato group at NTU | Establish the wireless communication of the backpack and the operator laptop. Configure the stimulus parameters and log the positional data. Visualize the flight data. | |
GINA base station | Kris Pister group at UC Berkeley | TI MSP430F2618 and AT86RF231 | |
Motion capture system | VICON | T160 | 8 cameras for a flight arena of 12.5 x 8 x 4 m |
Motion capture system | VICON | T40s | 12 cameras for a flight arena of 12.5 x 8 x 4 m |
Micro battery | Fullriver | 201013HS10C | 3.7V, 10 mAh |
Retro reflective tape | Reflexite | V92-1549-010150 | V92 reflective tape, silver color |
PFA-Insulated Silver Wire | A-M systems | 786000 | 127 µm bare, 177.8 µm coated, 3 mm bare silver flame exposed at tips |
SMT Micro Header | SAMTEC | FTSH-110-01-L-DV | 0.3 x 6 mm, bend to make a 3 mm long slider to secure the electrode into the PCB header. |
Beeswax | Secure the electrodes | ||
Dental Wax | Vertex | Immobilize the beetle | |
Insect pin | ROBOZ | RS-6082-30 | Size 00; 0.3mm Rod diameter; 0.03 mm tip width; 38 mm Length Make electrode guiding holes on cuticle |
Tweezers | DUMONT | RS-5015 | Pattern #5; .05 X .01mm Tip Size; 110mm Length Dissecting and implantation |
Scissors | ROBOZ | RS-5620 | Vannas Micro Dissecting Spring Scissors; Straight; 3mm Cutting Edge; 0.1mm Tip Width; 3" Overall Length Dissecting and implantation |
Potable soldering iron | DAIYO | DS241 | Reflow beeswax |
Hotplate | CORNING | PC-400D | Melting beeswax and dental wax |
Flourescent lamp | Philips | TL5 14W | Light the entire flight arena with 30 panels (60 x 60 cm2). Each panel has 3 lamps. 14 W, 549 mm x 17 mm |