Fig. 4: Untethered ankle exoskeleton.
From: Personalizing exoskeleton assistance while walking in the real world
a, A participant walking in a community setting wearing the exoskeleton. b, The exoskeleton consists of (1) a battery pack worn on the waist, (2) a motor, drum and rope transmission to produce assistive torques, (3) electronics to receive sensor data, command the motor and perform optimization, (4) a carbon fibre and aluminium frame to transmit forces, and (5) a shoe and (6) a calf strap to transfer forces to the body. c, The motor can apply a peak torque of 54 Nm when walking at 1.5 m s−1, sufficient to match the optimized assistance parameters identified in emulator experiments. Torques were tracked accurately; the shaded region represents the mean ± one standard deviation. d, The motor temperature during 30 min of walking with maximum assistance remained well below the 75 °C thermal limit. An exponential fit indicated a steady-state temperature of 35.4 °C.
