Thumper

Thumper
Participation Information
US 1994-1997 Events	1997
Team Information
Team Members	Bob Gross
From	Thousand Oaks, California
Robot Statistics
Power	2x 12V gel cell batteries running in series 24V; computer "brain" system with 9V battery
Drive	2x 12V DC motors
Weapons	Lifter
Statistics correct as of its most recent show/competition appearance, or if not applicable, qualification attempt.

Thumper was an autonomous robot built by Bob Gross for the 1997 US Robot Wars competition. Participating in demonstration battles, it defeated the then-incumbent Autonomous class champion Gladiator Rodney II in a one-off head-to-head, and fought conventional RC-operated heavyweight Hercules in an informal 'grudge match'.

Design

Built for the middleweight subclass, Thumper was a tall two-wheel drive robot with a mostly polypropylene construction. As further defense, it utilized scrap steel and aluminum panels on the exterior, chosen by Bob Gross to prevent it from being cut easily by circular saws. Internally, it was driven by two 12V DC motors running on two similarly-rated gel cell batteries running in series, for a total output of 24V. Resisters (rated at 1 ohm, 50 watts) were installed in the central relay control box to 'dissipate excess current', in case Thumper's motors exceeded their maximum load.

Thumper's main weapon was a front electric lifter, powered by two motors generating 1hp in total. A large spring was incorporated into the tall rear-hinged mechanism, which had the capability to adjust the lifter's power output depending on its intended function. While the lifter was programmed to lower at only 1/4hp, Thumper was designed to lift and potentially throw opponents at the motors' full 1hp output.

In terms of autonomous technology, the robot was operated by a compact, top-mounted computer system, itself programmed using a variation of BASIC software. Gross, emphasizing the need for the robot to be as simple and easy to program as possible, used the smallest processors available and created a custom 'division system' for the machine to operate on. Much of Thumper's systems were located inside its 'head', including a 9V battery and five IR receivers for front, sideways, rear and 'upward' processing. The 'upward' sensor was placed immediately beneath the standard beacon, enhancing Thumper's ability to distinguish between its own beacon and those fitted to other robots.

On either side of Thumper, a set of rotating arms with six-inch stainless steel spikes constantly revolved whenever the robot was in motion. According to Joseph W. Partlow, these were to both impale opponents and act as a secondary set of lifters. In combat, these arms proved effective as an unconventional self-righting mechanism, making Thumper one of the early pioneers of these devices in any Robot Wars competition.

Robot History

1997 US Championship

Thumper's 1997 campaign began with a one-off Autonomous-class battle, against defending champion Gladiator Rodney II.

During the opening moments, it took advantage of its opponent's slow bootup time, approaching, pushing and tipping it onto its back end before Gladiator Rodney II could prepare a counterattack. Thumper held Gladiator Rodney II in place as the latter rocked back, then spun it around. After a few more seconds, it tried to lift Camp Peavy's machine, but missed with its first two attempts. Another push and a third lift allowed Thumper to turn Gladiator Rodney II onto its side. Thumper spun jubilantly in circles as Michael Meehan immediately declared it the winner and the 1997 Autonomous Champion.

"... I was asked/challenged by one of the autonomous robot creators- "Thumper" if I would like to do battle against him (he had alredy beaten the tar out of the only other autonomous robots). By then, I was feeling a little more confident with my makeshift control system (we even got the mixing feature working again on my Radio transmitter, so steering wasn't nearly so hard as before), so I said sure!"

— Jim Smentowski, on the Thumper/Hercules battle

Following Thumper's victory, Bob Gross contacted Jim Smentowski - builder of Hercules - to arrange an exhibition 'grudge match' between the two machines. The demonstration enabled a comparison between the fully-autonomous competitors of the day, and a conventional remote-controlled heavyweight. To allow Thumper to track its opponent's movements, a standard IR beacon was attached to Hercules ahead of this fight.

Thumper was the first robot to move, as the opening moments were used to demonstrate its autonomous functions. It approached, gently nudged and lifted Hercules' flail arm, before following the latter around as the official start countdown was initiated. Once the battle began, both robots exchanged collisions with each other, before Thumper pinned Hercules against the wall for a few seconds. After this, it kept following Hercules back across the center, exchanging weapon attacks with it before pinning Hercules against the upper-left corner. The pin resulted in Thumper's lifter being clamped down by Hercules' own arm, as Michael Meehan proceeded to explain the process of separating competitors to audience members.

Thumper is caught and carried by Hercules

On cue, a separation was called and carried out. After the two competitors were dragged out of the corner by a Robot Wars crewmember, Thumper twitched around in place as Hercules turned and drove towards the center. It became clear that Bob Gross' machine was no longer able to move translationally across the arena. Thumper was rendered helpless as Hercules approached, nudged, then started tipping it onto its side. Smoke began pouring from beneath Thumper as it was hooked, lifted and carried across the arena in Hercules' arm. A rubber strap mounted to the front of Thumper got entangled, preventing Hercules from being able to shake itself free. Regardless, Thumper was pushed towards the upper-right corner, before the fight was again stopped to allow a separation.

Thumper topples

Following the second restart, Thumper was driven against the wall and tipped onto its right-hand side by Hercules. A few seconds later, it levered itself back onto its wheels with one of its rotating arms. At that point, Hercules lifted Thumper a second time, leaving it balancing on its other side arm. Thumper was soon toppled over and propped up against the side wall, its self-righting capability now nullified. Hercules was declared the winner, marking the end of Thumper's only US Robot Wars appearance.

Results

Wins/Losses

• Wins: 1
• Losses: 1

Series Record

Events	Thumper Event Record
1994	Did not enter
1995	Did not enter
1996	Did not enter
1997	Autonomous Champion (Middleweight)

External Links

• Thumper on Joseph W. Partlow's website (archived)