Robots were first cast as characters in drama in the twentieth century with Karel Čapek’s R.U.R. (first published in 1920; first performed in 1921); notably, this was the play that coined the word ‘robot’.
It was not until much later in the century that robot characters started reappearing on Western stages with any frequency, in plays including Alan Ayckbourn’s Henceforward (1987), Comic Potential (1999), and Surprises (2012), as well as some tongue-in-cheek science fiction plays and musicals, such as Return to the Forbidden Planet (which won the Olivier award in 1989 and 1990 for Best New Musical, and enjoyed a revival in the UK in 2015).
However, in all these works, crucially, human actors performed the robot characters; robots never performed themselves. The practice of robots performing versions of themselves on stage is a markedly recent one.
The twenty-first century has seen playwrights and theatre-makers starting to respond to the socio-historical technological proposition of robots.
In 2006, Elizabeth Meriwether’s play, Heddatron, was performed by Les Freres Corbusier in New York. As far as I can ascertain, Heddatron was the first play to feature robots on stage performing robot characters. (Richard Maxwell’s Joe  precedes Heddatron but its life-size robot functions metaphorically in the piece ‘as the representative of the final stage of the [human] character Joe’s life’ [Parker-Starbuck, Cyborg Theatre, p. 54], as opposed to being an android character in its own right.)
Since its first production off-off Broadway, Heddatron has enjoyed multiple further productions in North America (including by Sideshow Theatre Company) and in its wake a raft of other plays featuring robots performing robot characters has followed. A sample of these are listed below.
The Uncanny Valley by Francesca Talenti was performed in October 2013 at Swain Hall, UNC, and again in July and October 2014 at The Brick Theater, New York. Both productions cast a real robot performer called RoboThespian™ (made by Engineered Arts in Cornwall, UK) amongst the play’s dramatis personae, the same model of robot that continues to perform at the Copernicus Science Centre in Warsaw in a number of short plays, which are based on work by such writers as Hans Christian Anderson and the Polish science fiction author, Stanislaw Lem.
Meanwhile, the theatre academic and philosopher David Z. Saltz has experimented with the performative potential of Robotis’s DARwin-OP robot by employing the five hundred year old theatre tradition of Commedia dell’Arte to devise a play, Commedia Robotica (December 2012).
In 2012, Free Theatre Christchurch, in collaboration with the HIT Lab NZ (University of Canterbury), performed I Sing the Body Electric, based on the Don Juan legend, and cast two NAO robots on stage in a play that foregrounds gender and its performance, as well as the insatiable human desire for advancing technology.
In the autumn of 2013, Calgary’s Swallow-a-Bicycle Theatre company performed their play, I-ROBOT Theatre, based on the poetry of Jason Christie (I-ROBOT Poetry).
Les Voyages Extraordinaire staged their wordless play, Robots, which was written and directed by Christian Denisart, at the Théâtre Barnabé in Switzerland in 2009. The play featured two human actors and three robots, including a humanoid robot whose grace and fluidity of movement in her upper body, produces some really uncanny effects.
There are many more plays featuring robot characters that are performed by human actors. My favourite is The Uncanny Valley (2013) by Superbolt Theatre Company. This play is a love story between a female robot and a human male. It continues to have revivals, most recently being performed to school children in Norway (January 2016).
In June and July 2015, My Square Lady was performed at the Komische Oper Berlin. Starring in this piece (which was inspired by the musical, My Fair Lady, and George Bernard Shaw’s play, Pygmalion), was Myon, an autonomous learning robot whose education to become more human and to understand theatre comprised the subjects of the performance.
Most remarkable of all about this surprising ‘opera’ by Gob Squad (in collaboration with the Komische Oper Berlin) is the fact that Myon’s performance was ‘his’ own. As far as I know, Myon is the first of his kind: an ‘improvising’, autonomous robot (as opposed to a mechanical puppet).