An ecosystem of laboratories in hundreds of secret workshops is leveraging innovation to create a robot army that Ukraine hopes will kill Russian troops and save its own wounded soldiers and civilians. Defense startups across Ukraine — about 250 according to industry estimates — are creating the killing machines at secret locations that typically look like rural car repair shops. Employees at a startup run by entrepreneur Andrii Denysenko can put together an unmanned ground vehicle called the Odyssey in four days at a shed used by the company.