An Ultrasound ASIC With Universal Energy Recycling for >7-m All-Weather Metamorphic Robotic Vision

Abstract

An ultrasound ASIC that enables compact, 3-D nonvisual robotic navigation for >7-m is presented. The proposed ultrasound ASIC mitigates the limitations of camera vision navigation systems in all-weather, low-power, low-cost aspects. The ASIC integrates TX and RX paths for 64 channels, enabling four-directional navigation using 4 × 4 ultrasound arrays. The proposed universal energy recycling transmitter (UERTX) driver circuit, which can drive both single-ended and differential transducers, reduces energy consumption by 44% compared with non-overlap switching-assisted conventional class-D ultrasonic drivers, addressing large TX power consumption. In addition, the on- chip programmable power management unit (PMU) eliminates off-chip supplies and reduces off-chip passive components for compact system miniaturization. Furthermore, PMU enables the tuning of TX driving amplitude for the range of 6-14 Vpp allowing wide detection range adaptability. Fabricated in 0.18 μm 1P6M standard CMOS, the ASIC system measures 25 mm2 and has >7-m obstacle detection capability while consuming 4.3 mW/channel. The proposed ultrasound ASIC system is demonstrated with a four fps, 3-D navigating metamorphic robot, which consumes 0.28 W, occupies 125 cm3, and weighs ≤100 g.