Science and Culture: Light-seeking mobile houseplants raise big questions about the future of technology
Amy McDermott
Houseplants on wheels roamed the hallways of Rutgers University in New Jersey, beginning in 2012, sunning themselves in bright windows and asking students for water when their soil was dry. No remote control directed them. No unseen hand guided their movement. The mobile plants, called FloraBorgs, drove themselves.
Indoor plants are popular. By some accounts, millennials have become houseplant addicts (1); a quick search of Instagram, Pinterest, or Etsy turns up hundreds of thousands of images of trendy fiddle-leaf figs and slick-leaved monsteras. Hence, placing a fern on a roving base may seem part and parcel of a passing fad.
But beneath the cute veneer, a mobile, self-sufficient plant raises profound questions about man’s relationship with other species, the role of technology, and the line between organic and machine. A handful of similar projects combining houseplants and robots have cropped up in the past 10 years or so. Most are artistically and philosophically motivated. All explore the intersection of humanity, nature, and technology.
RoboGardens
Sculptor Elizabeth Demaray created the FloraBorg project to empower those houseplants to pursue their own needs. Each sits on a three-wheeled base that seeks light and water autonomously. It’s a comment on mankind’s often neglectful relationship with other species, she says. Demaray collaborated with engineer Qingze Zou, computer scientist Ahmed Elgammal (both of Rutgers University), and biologist Simeon Kotchoni previously at Rutgers University, and now at California Northstate University in Elk Grove, to give plants the freedom to care for themselves; a call for closer attention to the natural world.
“I think there’s a bit of a zeitgeist,” Demaray says. “Since starting this project, so many people have started making their own robotic plants.” Her motivations were purely artistic — to draw attention to nonhuman life. Other projects have different inspirations, their creators say, but also confront questions about nature and technology.
Most varieties of cyborg plants hunt for light, but they each work a little differently. FloraBorgs rattled down the halls of Rutgers at knee height, looking like animals, with plumes of leafy hair protruding from pyramid-shaped carriages on wheels. Solar panels line their three sides, sensing light, charging the battery, and communicating with a small Arduino computer nestled inside the housing. The Arduino moves toward the brightest light in the room, communicates with sonar sensors on the carriage to avoid obstacles, and interfaces with a soil-moisture sensor to find a nearby water cooler when the soil is dry.
A similar body plan graces the Soybots of Purdue University, in West Lafayette, IN. These modified Roomba robots have extra hardware to carry growing soybean plants. Big, leafy hockey pucks on wheels, they carry two photocells on either side, allowing each bot to compare light on its left and right and move in the brighter direction. New media artists Shannon McMullen and Fabian Winkler set out to probe the intersection of life and technology with an eye toward agriculture in particular. They’ve exhibited the work at Purdue and Arizona State University in Tempe.
The roaming plant is a poster child for debates over genetic engineering, which can increase crop yields and improve food security, but is also associated with woes of industrial farming. These are big issues in Indiana, the fifth-largest soybean-growing state in the nation (2), producing 346 million bushels in 2018, according to the US Department of Agriculture (3). Although McMullen and Winkler do not have a singular message for viewers, they hope their Soybots raise questions about the relationship between nature and technology and what desirable, ecologically informed or undesirable, overindustrialized agricultural futures might look like.
“I figure we have about six months before Walmart comes out with their own line of FloraBorgs.”
— Elizabeth Demaray
Chinese roboticist and entrepreneur Tianqi Sun explores “the border between plant, animal, and robot” with his mobile plant, which he first crafted in 2014 after seeing a dead sunflower sitting in a shadow. Could it have survived, he wondered, if only it had moved into a brighter spot? Sun installed a succulent on a mobile base, first handmade with PVC boards, to challenge the innate immobility of plants. A newer iteration sits on a six-legged crab-like robot, called Hexa, which is sold via Sun’s company Vincross. The robot monitors the environment using a camera, Sun explained by email, and is preprogrammed to sun itself matching the light needs of the succulent.
True Hybrids
Plants are natural sensors, detecting sunlight and releasing a wave of chemicals to turn their leaves toward it (4). Assembly is not required, yet most plant–robot projects use solar panels or photocells to sense sunlight rather than harnessing the plant’s natural capabilities. Bioroboticist Harpreet Sareen of Parson’s School of Design in New York, NY, and Massachusetts Institute of Technology in Cambridge sought a different approach, one that uses the plant itself as the photosensor — creating a true hybrid between organic and machine, and pointing out the nonnecessity of reliance on artificial products.
Called Elowan, the project connects a houseplant and a mobile base using fine wire electrodes poking into stems on either side of the plant. The electrodes detect calcium gradients, a kind of chemical signal produced when a plant senses light, Sareen says. The calcium reacts with silver chloride at the electrode tip, producing electricity. Only then does the electrode communicate with a robotic base that moves in the direction of the signal.
Sareen designed Elowan to show that modern production processes could be environmentally friendlier and less artificial. Why build electronics that gobble energy and use synthetic materials, he asks, when biodegradable plants already do the job? “We want to design electronics,” he says, “in conjunction with the natural capabilities that exist in the environment.” Elowan’s robotic base doesn’t have an “on” button. No light sensors or preprogrammed settings care for the plant. The machine doesn’t work unless the plant does.
Sareen attributes the recent explosion of plant–robot combinations to existential dread about humanity’s exploitative relationship with the environment. In the marriage of nature and technology, he sees an urge to fix things. “We are desperate to look for ideas that can propagate that change,” he says. No single project claims to answer all of the grand questions it poses. Questions are the point in most cases.
As it happens, all these creations are also quite likable. Audiences often view them as pets, McMullen says. The emotional attachments are faster and more intense than she expected — one more example of the blurring edge between life and technology. Likable as they are, none of these projects are widely commercially available, although Hexa’s robotic base is sold online.
Commercialization treads narrowly between advancing and undermining the point. Sareen is developing commercial kits that would facilitate responses to environmental signals but is careful to avoid anthropomorphism, he says. He’s interested in design to better understand species, not to domesticate them. “We are not designing a self-caring plant for a home per se,” Sareen notes, adding that they’re instead aiming to design “bionic plants or plants with prosthetics” to reflect how we humans are “augmenting ourselves in this changing environment.”
Demaray thinks it’s just a matter of time before cyborgs hit the shelves of retail stores, and she would welcome them, as long as the technology continues to benefit plants. “I figure we have about six months,” she says, “before Walmart comes out with their own line of FloraBorgs.”
Published under the PNAS license.
