Scientists kill spiders and turn them into clawed ‘necrobots’

Researchers have used deceased spiders’ legs as mechanical grippers in a macabre experiment.

Rice University mechanical engineers have been developing “necrobots” based on existing research of using non-traditional materials like hydrogels and elastomers that can reach to chemicals or light – in this instance using a spider that they killed and experimented on.

“This area of soft robotics is a lot of fun because we get to use previously untapped types of actuation and materials,” said Daniel Preston of Rice University’s George R. Brown School of Engineering.

“The spider falls into this line of inquiry. It’s something that hasn’t been used before but has a lot of potential.”

Spiders use hydraulics to move their limbs, rather than muscles. A chamber near their head contracts to send blood to the limbs, and when it expands the legs extend and release.

“We were moving stuff around in the lab and we noticed a curled up spider at the edge of the hallway,” Rice graduate student Faye Yap said. “We were really curious as to why spiders curl up after they die.”

The reason is that spiders do not have antagonistic muscle pairs, like biceps and triceps in humans, but rather have flexor muscles that curl and extend. This is why, when spiders die, they curl up – because they have lost the ability to actively pressurize their bodies.

The researchers tapped into the prosoma chamber – which controls the legs – with a needle and superglue. The other end of the needle is connected to a syringe that delivers air to the legs.

This lets the researchers control the legs for various projects. “There are a lot of pick-and-place tasks we could look into, repetitive tasks like sorting or moving objects around at these small scales, and maybe even things like assembly of microelectronics,” Mr Preston said. It could also be used to capture smaller insects, because of its inherent camoflague.

“The spiders themselves are biodegradable,” Mr Preston said. “So we’re not introducing a big waste stream, which can be a problem with more traditional components.”

The research has been published in an open-access study in Advanced Science.