Read Online Pyramid Lake by Paul Draker - Free Book Online Page A

of its wrists to the ground and straightened its legs behind. Its chest dipped and rose jerkily in a series of pushups.
    “Why the anthropomorphic shape?” Cassie asked.
    “The earliest prototypes were wheeled autonomous vehicles,” Blake said. “But the modern battlefield is often in urban terrain—moving over broken rubble, fighting house-to-house, even. Wheeled platforms could not always follow the warfighter to where he or she needed to be.”
    He led us deeper into the lab, which resembled a machine shop. Prototypes and parts lay among the CNC-controlled lathes, milling and cutting machines, and drill presses. We passed variant PETMAN torsos, arms, and legs lying on worktables, and older models that did not resemble human anatomy at all.
    “The second-generation platforms—BIGDOG, ALPHADOG, and CHEETAH—were modeled after rescue canines.” Blake pointed at a group of waist-high quadrupedal robots with horizontal bodies. “ALPHADOG was optimized for carrying capacity, BIGDOG for stable movement over broken terrain, and CHEETAH for speed.”
    The spindly, multijointed legs of ALPHADOG and BIGDOG looked like they belonged on a metal gazelle rather than a dog. CHEETAH’s longer legs were different, tucked under its body in exaggerated Z-shaped folds. They tapered to end in sharp metal points.
    Cassie looked at them and shuddered. “ Ugh. Like the arms of a giant steel praying mantis.”
    “And they move as fast as a mantis can strike,” Blake said. “CHEETAH can run thirty-five miles an hour. But PETMAN is a far superior platform for the mission. We needed a solution that could accompany the warfighter anywhere, in and out of vehicles and buildings—”
    “—as long as the elevators still work,” I said, and snickered.
    Blake’s pouchy face soured.
    “Stairs are still a problem for PETMAN,” he said. “But we’re making progress.”
    He led us back to where the robot was still banging out pushup after relentless pushup.
    “Every time it tries the stairs, it falls,” I told Cassie. “Like some wobbly old drunk.”
    “I still don’t understand why,” Blake said. “He’s got great dynamic balance.” He tapped his iPad. PETMAN rose to stand upright, red light flashing, and began to walk again. Then it accelerated to a lurching run on the custom treadmill. The soles of its Nikes struck the treadmill’s steel mesh with loud hammering sounds.
    “Watch.” Blake reached out and gave PETMAN’s shoulder a hard push. The robot took a sideways step but maintained its balance, never breaking stride. He shoved it again, causing it to stumble slightly, but once again PETMAN recovered.
    Blake grinned at us and raised a foot high, planting it against PETMAN’s hip. He thrust his leg violently, sending it staggering.
    My stomach tensed.
    This time the robot’s arms came up as it stabilized itself, but it maintained its forward run.
    The blank equanimity with which PETMAN took the abuse was disturbing to watch—like it was holding itself back, biding its time. I half-expected it to take a swing at Blake any moment now.
    Cassie turned away, but I caught the troubled look on her face. “How much can PETMAN carry?” she asked.
    Blake dragged a thick ceiling-tethered power cord over and plugged it into the running robot’s back. “He weighs four hundred seventy-five pounds, and can carry eleven hundred additional pounds of payload,” he said, sounding like a proud father.
    Cassie asked about PETMAN’s battery life. While Blake answered her, I turned away and slipped out my phone. I tapped a few commands, then put the phone back in my pocket.
    “…three hundred fifty watt-hours per kilogram.” Blake held out a flat, silvery battery module the size of a DVD case. Cassie inspected it and handed it back, then he slid it into a rectangular array that held dozens of similar modules. “PETMAN’s fifty-pound battery pack allows twelve hours of strenuous untethered operation,” he said.
    Behind them, the