Crossfire

Crossfire with its team

**Crossfire** (Chinese: **封锁火线**, romanized as **Fēngsuǒ huǒxiàn**, directly translating to **Block Fire**) was a robot from Scotland which competed in the first season of *King of Bots*. Built and entered by Team Far North – captained by former *Robot Wars* UK champion Gary Cairns – it lost its first-round battle to The Grubs after getting thrown by a floor flipper, damaged and being left stranded on its own weapon assembly. Through the wildcard, it was reinstated and rejoined the competition during the third round, but was defeated by the American Spin Doctor.

Team Far North entered Season 1.5 of *This is Fighting Robots* with 008, thus retiring Crossfire.

## Design

Crossfire was a large, invertible robot propelled by two outward-facing wheels and supported by four spring-cushioned ‘legs’ with castors forming an ‘X’-shape. Its weapons were a face-mounted horizontal bar spinner with a diameter of 1 meter – which spun at 2,000rpm – and a flamethrower mounted beneath the spinner mount. Crossfire’s symmetrical design gave it 360 degrees of offense and defence, while the weapon assembly was mounted on a pivot, allowing it to swivel whenever the robot lifted itself up vertically or onto one side. It took some design inspiration from the fairyweight competitor **No Fly Zone**.

"*I knew from the start, it was unlikely to be a successful machine. There was a hope that it would somehow turn out to be a champ but I knew the legs were fragile and the drive was unlikely to be quick. Because of the location of the wheels relative to the front of the robot along with the huge gyro forces I was going to be fighting, I had to angle them to give it bias towards turning. This would also hopefully keep the bar pointing in the right direction. The downside being that it made it a pig to go in a straight line with any kind of speed as the wheels were fighting each other.*"
— Gary Cairns

## Qualification

The Far North team were not initially selected to compete in Season 1, as *King of Bots* placed a greater emphasis on collecting established roboteers before looking at individual designs. As a result, the team were instead placed on the waiting list for potential reserves. Following further correspondence with Cairns, the *King of Bots* producers ultimately selected Crossfire for the show after responding favourably to an early CAD model of the robot.

"*Back when applications were being taken for King of Bots I was relaxing in a French Villa with my new wife drinking some lovely local wine. I took a quick glance at the application and decided, yeah why not. The application itself was exceptionally short and only asked what you had built previously. It never asked what you intended to build for the show. Over another glass or two of wine I finished the application and thought nothing more of it. I’d mentioned bits and pieces with Robot Wars and just assumed that they would get in touch for more info as to what you intended to enter.I got an email a month or so later that said essentially thanks but no thanks. You’re on the waiting list. I understood this to mean that there was sod all chance of us taking part. I decided to be a little bit cheeky. I emailed back and said that the design I had in mind was so different that nothing similar had ever been seen in the heavyweight fighting category (bit more to it but that’s the jist). I got a message back asking me for a CAD model. Bugger, right I need to show a design so crazy that they will fall in love with it instantly and want it on the show no matter what. Crossfire was born. Hints of no fly zone in there, along with a few other machines. The first CAD I sent was incredibly basic and only gave a hint of the robot’s shape. They loved it. We were on the show.*"
— Gary Cairns

## Robot History

### King of Bots (Season 1)

Crossfire appeared in Episode 3, where it fought fellow UK entry The Grubs in the first round. Slowly, it manoeuvred out of the blue square, driving towards and past one of the floor flippers before proceeding to turn around in circles over the floor rods. As it tried to turn and attack Chop, Crossfire repeatedly lifted its bottom castors off the floor, causing its entire weapon assembly to swivel in the process. It continued to pursue Chop, only to lift and hold its weapon assembly off the floor as it spun round on the spot. The weight of Crossfire’s weapon caused the whole robot to overbalance and manoeuvre towards the nearest floor flipper, while simultaneously exposing it to a side-on attack from Chop.

The flipper threw both robots simultaneously, with Crossfire tipping onto one side before landing upright onto the flipper. Immediately, the floor flipper threw Crossfire again, this time across the arena and into Mince, albeit not without its bar spinner tearing a chunk out of the flipper’s edge. The collisions with the floor and Mince broke the suspension of two of Crossfire’s ‘legs’, leaving it resting on its weapon assembly. With its rear wheels lifted off the floor, it was unable to drive any further; as a result, Crossfire was counted out and lost the battle by knockout.

"*Aye, it was wonderful! We were dancing about in the arena, and… I guess we forgot that were meant to be fighting!*"
— Gary Cairns on Crossfire's impromptu pirouette

However, Crossfire's campaign had not yet ended, as Team Far North's innovative design was rewarded by the producers, who awarded one of four wildcard positions to Crossfire, which allowed it to skip straight to the third round. There, it faced a fellow wildcard which had lost in the first round, Spin Doctor from the United States of America.

"*When we got the wildcard, I think we were surprised, shocked. Spin Doctor is a very strong robot. I think, really, the only thing we can do is to spin up our bar as fast as possible, and do our best to try and get around the side of the robot.*"
— Gary Cairns on the wildcard, and the battle with Spin Doctor

Crossfire immediately spun up its blade, and kept its weapon facing Spin Doctor while also activating the smokescreen in front of the American team. This tactic was returned, with no effect on the battle. Still circling in place to protect its back end, Crossfire taunted Spin Doctor using its flamethrower, but the drum spinner finally drove under Crossfire, and then drove into its back end while using its own flamethrower. The weaponry of both robots collided near the arena wall, throwing sparks while also disabling the weapon of Crossfire. While Spin Doctor pushed Crossfire away from this area, a piece of Crossfire's back end was ripped away, and it became clear that Crossfire had been immobilized. It was counted out, and eliminated from the competition for a second time.

"*You know, we were the underdog to a certain extent, and we might've gotten lucky. We didn't in this instance, but it was a good, fun fight. I enjoyed it, I had a good bit of fun with it.*"
— Gary Cairns

Crossfire also fought in a nine-robot Rumble held at the end of Season 1. There, it fought alongside Blue, Dark Knight, Griffin, Ink Thorns, Nuclear Bomb, Steel Dragon, The Grubs and Violent Dragon. Initially, Crossfire twitched in its starting position, getting its bar spinner up to speed before turning towards Blue and lifting its weapon assembly into the air. Sparks flew as Crossfire’s spinner made contact with Blue’s axe head, the impact also resulting in the suspension for one of its legs breaking off. Spinning madly in the center of the arena, Crossfire ejected one of its own castor wheels, before being pushed sideways by Griffin. Eventually, Crossfire’s bar spinner stopped rotating by the time it and Griffin lingered near the wall spikes; Crossfire itself was then pushed into the wall and an immobile Ink Thorns by Dark Knight. At that moment, it sustained an axe blow from Blue which forced the bar spinner down; as a result, the electronics for the spinner short-circuited, leaving Crossfire without a working weapon. Moments later, Crossfire was lifted by the floor rods along with Dark Knight, which proceeded to push it and Ink Thorns across the arena simultaneously.

Crossfire escaped, but not without sustaining damage to another of its legs from Chop – the orange segment of The Grubs. It drove away, only to sustain another attack from Chop, and after occasionally bumping into its remaining opponents was eventually pushed around by Nuclear Bomb. Crossfire spun round and slowly drove towards Nuclear Bomb, only to drive away from the latter and attempt to push Dark Knight. Eventually, it crawled towards Violent Dragon and stopped moving altogether, ultimately losing the Rumble to Nuclear Bomb.

## Results

### Wins/Losses

* Wins: 0
* Losses: 3

## Outside King of Bots

Prior to entering *King of Bots*, Gary Cairns earned several years of robot combat experience through competing in the UK TV shows *Robot Wars* and *Techno Games*. He initially competed in the latter shows as part of **Team Typhoon**, a team consisting of cadets from the Air Training Corps, where he served as one of their drivers. Among the team’s most famous and successful robots were the **Typhoon** series of full-body spinners, which were built to compete in different weight classes and featured cone-shaped bodies painted to resemble the roundel of the British Royal Air Force (RAF). Cairns drove the original version of Typhoon, which won three consecutive Middleweight Championships during the original run of *Robot Wars*, as well as a heavyweight derivative, **Typhoon 2**, which won the seventh series outright before making a one-off appearance at RoboGames in 2005.

Following *Robot Wars*’ initial cancellation, Cairns built an invertible horizontal spinner, **Swarm**, with the intention of competing with it in the 2006 UK Championships. However, Swarm was forced to withdraw from the championship due to technical issues, and did not appear at any live events thereafter.

Although Team Typhoon did not return for *Robot Wars*’ revival in 2016, Cairns formed his own team, **PP3D Robotics**, to compete in Series 8-9 of the rebooted show. Their entry for these series, **PP3D**, was an invertible robot utilising an undercutting flywheel and 3D-printed parts. It reached the second round in both of its appearances, but ultimately progressed no further.

## References

1. ↑ https://www.reddit.com/r/battlebots/comments/7s6c9f/crossfire\_a\_builders\_perspective\_no\_spoilers/
2. ↑ https://www.reddit.com/r/battlebots/comments/7s6c9f/crossfire\_a\_builders\_perspective\_no\_spoilers/
3. ↑ https://www.reddit.com/r/battlebots/comments/7s6c9f/crossfire\_a\_builders\_perspective\_no\_spoilers/

## External Links

* Team Far North - King of Bots Facebook page
* Official PP3D Robotics (Far North) team website
* Crossfire on the official *King of Bots* website (Chinese, archived)
* Team Typhoon and PP3D Robotics on *Robot Wars Wiki*