In July 2012, Ahmad Haidar saw a young man die at the hands of a Syrian army sniper on an Aleppo street.
The first shot had hit a leg and onlookers felt it was a deliberate attempt to incapacitate, which Haidar says is a common tactic intended to lure out rescuers. Aware of this, the onlookers, unable to approach the victim, desperately struggled to pull him to safety using ropes and poles.
"He was trying to get behind cover and people tried to help with anything that was there," Haidar recalls. The sniper fired again, a lethal shot to the neck.
Haidar thought there was a way he could help.
Drawing on his expertise in electronics and computer programming, he devised a hi-tech response to Syrian president Bashar al-Assad's snipers in a caterpillar-tracked, remote-controlled robot equipped with large mechanical arms.
It is designed to pick up wounded people and place them on a stretcher inside an armoured compartment and move to safety. Haidar named it "Tena", after a Finnish woman he once sat next to on an airline flight.
Haidar and his childhood friend Belal, an engineer, have spent the past seven months fabricating and assembling Tena in a nondescript workshop on the outskirts of a Turkish border town. Its robotic arms, the most complex and technically demanding components, are now complete. Next, they need a bulldozer chassis to mount them on.
Haidar attempted to crowd- fund the project on robotena.org  but so far it has not generated the money required. As a result, he has exhausted personal savings to meet the costs.
A rebel group said it would provide a vehicle, but the machine was too large and offered only on condition that Haidar create weapons in return. He refused. The project also has been discussed with aid agencies, but without success.