a, Two-bladder actuator design in which traces (i) are printed in contact with the hyperelastic layer (ii) inside the body matrix material (iii) and differences in modulus result in bending upon inflation. The thickness, h, of the hyperelastic layer is modified to change the characteristics of the actuator. In this example, the body matrix material (iii) has a height of 800 μm. b, Top, the actuator tip angle, θ, changes upon inflation. Scale bar, 10 mm. Bottom, mean displacement angle, θ, taken from three representative actuators during five inflation cycles as a function of inflation pressure, for varying hyperelastic layer heights, h (in μm). Error bars, denoted by the shaded regions, indicate the 95% confidence interval. c, The oscillator of the soft controller causes an octobot to alternate between blue and red actuation states. The monopropellant fuel is dyed to show states. Scale bar, 5 mm. d, Stills from top-down (top; Supplementary Video 5) and face-on (bottom; Supplementary Video 6) operation videos show an octobot autonomously alternating between blue (‘1’) and red (‘2’) actuation states. Scale bars, 10 mm.