Sex robots have the potential to provide a valuable service for people who are elderly, disabled or who find intercourse traumatic, but they also carry ethical risks, experts say.

Sex robots that look like humans can already be bought or leased for parties in the US, and plans for a cafe staffed by “erotic cyborgs” in Paddington, London, have been mooted.

The authors behind the Foundation for Responsible Robotics’ (FRR) report, published on Wednesday, believe they could herald a “revolution” in sex, helping people who would otherwise find it hard to have intimate relationships.

But they also raise concerns that sex robots could increase the objectification of women, alter perceptions of consent and be used to satisfy desires that would otherwise be illegal.

Dr Aimee van Wynsberghe, assistant professor in ethics and technology at the Technical University of Delft and FRR co-director, said: “If we are talking about individuals who are not only disabled but have been traumatised, in some ways this could be a beneficial instrument, if you will, to help them in their [sexual] healing process.

“There are absolutely some benefits to the technology but, like everything else, there is a balance. You have to strike a balance between lack of regulation – so we have all different uses and personifications of children and women as sexual objects – or you have overregulation and you stifle the technology. You have to find the way to balance so you really can harness the good.”

Among the people it is proposed could benefit from interaction with sex robots are elderly people in care homes, people of both sexes who have had a traumatic sexual experience and men who suffer from erectile dysfunction or premature ejaculation.

Report co-author Noel Sharkey, professor of artificial intelligence and robotics at Sheffield University, said their popularity will ultimately be determined by how realistic they are and their social acceptability. While robots look similar to humans, their movements and speech are still crude, said Sharkey, making them a far cry from the robotic bordello hosts in the HBO series Westworld.

“It might be a little niche thing or it might be something that stag nights go to,” said Sharkey. He also raised the prospect of it being a “safe way” for couples to experience a ménage à trois.

Four manufacturers are currently making sex robots, ranging in price from $5,000 (£3,870) to $15,000, but the intention is to eventually make them more affordable.

Among those available is the RoxxxyGold, about which there has been some disquiet because of a selectable mode – Frigid Farah – in which its personality is described as “reserved and shy”. A paper published earlier this year said the manufacturer claimed that if “you touched her in a private area, more than likely, she will not be to[o] appreciative of your advance”, leading some to claim that it is indulging rape fantasies.

Sharkey said: “Some people say: ‘Well, it’s better they rape robots than rape real people.’ That’s one of the arguments … you can have enjoyable [sex] with your wife - all nice - but when it comes to rape, you have a rape fantasy, you go off and rape a robot. But there’s other people saying this will just encourage rapists more.”

There are also fears that child sex robots could be created. There are already child sex dolls made by a Japanese company owned by a self-confessed paedophile, who claims they prevent him and other paedophiles abusing real children. However, Sharkey is sceptical of the argument that robots can help people get over rape or child sex fantasies, suggesting it is more likely to “encourage paedophilia and make it acceptable to assault children”.

The report quotes Patrick Lin, director of the ethics and emerging sciences group, at California Polytechnic State University, who says: “Treating paedophiles with robot sex-children is both a dubious and repulsive idea. Imagine treating racism by letting a bigot abuse a brown robot. Would that work? Probably not.”

Both male and female robots are available, but there are particular concerns they could amplify objectification of women, with complaints that female versions are based on representations garnered from pornography. They could affect human interactions in other ways, suggests van Wynsberghe.

“Sex robots are an interesting case study, if you will, to look at the main issues we face with robotics, writ large,” she said. “So this idea of moral de-skilling ... we’re interacting with the robots in these companionship, personalised ways and what kind of consequences does that have on the human users? Does that mean we won’t want to interact with humans any more because it’s just easier to talk to the robot or easier to engage in sexual gratification with the robot?”