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Computer-Controlled Swarm of Bacteria Builds Tiny Pyramid

Researchers are putting swarms of bacteria to work, using them to perform micro-manipulations, propel microrobots, and act as biosensors

2 min read
Computer-Controlled Swarm of Bacteria Builds Tiny Pyramid

Researchers at the NanoRobotics Laboratory of the École Polytechnique de Montréal, in Canada, are putting swarms of bacteria to work, using them to perform micro-manipulations and even propel microrobots.

Led by Professor Sylvain Martel, the researchers want to use flagellated bacteria to carry drugs into tumors, act as sensing agents for detecting pathogens, and operate micro-factories that could perform pharmacological and genetic tests.

They also want to use the bacteria as micro-workers for building things. Things like a tiny step pyramid.

The video below shows some 5,000 bacteria moving like a swarm of little fish, working together to transport tiny epoxy bricks and assemble a pyramidal structure -- all in 15 minutes.

The video was presented at the IEEE International Conference on Intelligent Robots and Systems last year, along with a wonderfully titled paper, "A Robotic Micro-Assembly Process Inspired By the Construction of the Ancient Pyramids and Relying on Several Thousands of Flagellated Bacteria Acting as Workers."

[youtube //www.youtube.com/v/fCSOdQK5PIY&hl=en_US&fs=1&color1=0x3a3a3a&color2=0x999999&hd=1 expand=1]

The bacteria, of a type known as magnetotactic, contain structures called magnetosomes, which function as a compass. In the presence of a magnetic field, the magnetosomes induce a torque on the bacteria, making them swim according to the direction of the field. Place a magnetic field pointing right and the bacteria will move right. Switch the field to point left and the bacteria will follow suit.

Each bacterium has flagella capable of generating about 4 piconewtons. It's a very small amount of thrust force, but put thousands of bacteria to work together and they can move mountains. Well, micro mountains.

Several research groups are trying to develop MEMS devices that emulate the propulsion mechanisms of bacteria. Martel asks, Why mimic the bacteria when you can use the little things themselves?

Martel and his colleagues developed an electronic microcircuit that contains both the bacteria and an array of conductors that produce magnetic fields. By carefully controlling which conductors are active, the microcircuit can make the bacteria move in specific directions. A computer and an optical microscope provide a feedback loop, tracking the motion of the bacteria and adjusting the conductors to achieve the desired behavior.

In addition to pyramid building, Martel's bacteria has done some other neattricks, such as traveling through the bloodstreams of rats, steered by an MRI system, a la "Fantastic Voyage."

One of their current projects is developing an autonomous bacterial microrobot. They plan to use standard CMOS processes to create a chip containing both electronics and bacteria. The bacteria would reside in micro-reservoirs designed to generate thrust. For control, small conductors inside each reservoir would produce magnetic fields.

Several of these microrobots could then be used to perform tasks collectively, perhaps one day swimming inside our bodies, delivering drugs, detecting disease, and fixing an organ here, a blood vessel there. Who knew bacteria could be good robots?

UPDATE:If you're wondering which ancient pyramid inspired the researchers -- and is shown in the video on the left bottom corner -- it's the Djoser step pyramid, in Egypt, which the researcher note was "an important,  initial milestone in the history of man-made structures."

Images and video: NanoRobotics Laboratory, École Polytechnique de Montréal

The Conversation (0)

How Robots Can Help Us Act and Feel Younger

Toyota’s Gill Pratt on enhancing independence in old age

10 min read
An illustration of a woman making a salad with robotic arms around her holding vegetables and other salad ingredients.
Dan Page
Blue

By 2050, the global population aged 65 or more will be nearly double what it is today. The number of people over the age of 80 will triple, approaching half a billion. Supporting an aging population is a worldwide concern, but this demographic shift is especially pronounced in Japan, where more than a third of Japanese will be 65 or older by midcentury.

Toyota Research Institute (TRI), which was established by Toyota Motor Corp. in 2015 to explore autonomous cars, robotics, and “human amplification technologies,” has also been focusing a significant portion of its research on ways to help older people maintain their health, happiness, and independence as long as possible. While an important goal in itself, improving self-sufficiency for the elderly also reduces the amount of support they need from society more broadly. And without technological help, sustaining this population in an effective and dignified manner will grow increasingly difficult—first in Japan, but globally soon after.

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