"Previous studies showed that this phenomenon affects images of people's faces and body postures, but not objects," said Mr Zlotowski, a PhD student at the university's human interface technology laboratory.
While it was not harder to recognise objects whether they were presented upright or upside down, it was more difficult to recognise human body postures presented upside down than when they were upright.
The images featured robots ranging from "humanoid" robots with hands to the more machine-like.
"Interestingly, we found that despite using images of various robots they were perceived cognitively more like humans than objects."
Dr Bartneck said the finding would probably mean humans would treat robots like themselves to a degree.
"We've been looking at how to improve interaction between robots and normal people, and the main motivation behind that is right now, we are at a point in history where consumer market robots are entering the market," Dr Bartneck said.
The first commercially available service robots had been designed to mow lawns and mop or vacuum floors, and now robots could be found as shopping assistants in malls or as tour guides in museums.
There were even cases of robots taking on the role of pets, forming emotional bonds with their users.
"We are going to get more and more of these, and we think it's important to investigate how they can be compatible with humans."
Robots were eventually expected to have everyday roles in our homes, making it important that we could feel "happy and satisfied" interacting with them, he said.
It was also likely robots would take on human traits to perform the tasks people did.
"In the environments ... these robots have to operate in, the home, everything is made to human scale."
Mr Zlotowski said it was highly likely robots would be adapted to more roles as technology developed.
"However, it will still take several decades before robots will be capable of behaving as depicted in sci-fi movies and books, such as Blade Runner or Wall-E."
Robots and us
The Uncanny Valley
A hypothesis dubbed the "uncanny valley" more than four decades ago claims that when robots or replicas act and look almost like humans, we react with disgust.
Japanese scientists even found babies responded badly and said it was a reason we should not create robots in human form.
But the University of Canterbury's Dr Christoph Bartneck said the results of several studies had challenged the theory.
Robots, leave those kids alone
A survey published last month by the European Commission found on average 86 per cent of respondents weren't comfortable with the idea of having robots mind their children.
Of those, 66 per cent were "totally uncomfortable" with this. A further 69 per cent didn't like the idea of having their dog walked by a robot, and 57 per cent weren't comfortable with having a robot perform a medical operation on them.
Cyber-sex in Amsterdam
A recent paper by Victoria University researchers theorised how robots could make for a cleaner sex trade in Amsterdam's red-light district by 2050, with councils controlling android sex workers clear of STIs, and an end to prostitutes being smuggled from Eastern Europe and forced into slavery. Picturing a futuristic sex club called Yub Yum, the paper theorised that "having sex with a robot is the future of sex tourism in Amsterdam".
