Eye on the Hog
Electronic sensor handles for detecting hog line violations in curling.
The Eye on the Hog is a curling officiating tool that uses electronics to catch hog line violations. Often called "sensor handles," the system stems from a University of Saskatchewan patent, later refined by Startco Engineering, which was eventually bought by Littelfuse.
The hog line violation rule itself dates to 1955. Ken Watson had popularized the "long slide" delivery at a time when most curlers barely left the hack. The slide became a gimmick for young players like Matt Baldwin and Stan Austman in the 1950s. To rein it in, the rule was changed in 1955, first limiting the slide to the tee line, then to the hog line in 1961, and finally requiring a clear release before the stone reaches the hog line in 1974. The penalty is removal of the stone. Both the 1974 Air Canada Silver Broom and the 1974 Macdonald Brier used the same rule requiring clear release before the hog line.
Enforcement originally relied on the honour system, similar to golf. Eventually, officials were used, like line judges in other sports. This raised concerns because visual calls are error-prone, and the rule puts the burden on the curler to remove all doubt. Canadian hog line officials were originally at ice level, then moved above ice level, and returned to ice level in 1985. Colleen Jones, penalized many times, argued the elevated position wasn't the best viewpoint. At the 1986 Labatt Brier, an out-of-town "enforcer" helped officials pull nine rocks in the first draw, including three by Mel Bernard. Controversy also surrounded Lyle Muyres, with films from an amateur filmmaker and a TV technician examined but not admitted as evidence. Other incidents involved Paul Savage and Russ Howard at the 1987 Ontario Tankard semifinal, Randy Ferbey at the 2001 World Men's Championship, and Colleen Jones at the 2002 World Women's Championship.
Neil Houston was key to the sensor technology's early development at the University of Saskatchewan. The Canadian Curling Association was the first to adopt it. After testing at Sutherland Curling Club, the sensor handle debuted at the 2003 Continental Cup, and the CCA quickly committed to using it in future events. Early on, curlers wearing gloves were still judged by officials, but rules later banned gloves to prevent circumventing the sensors. Rumours circulated that some M
- field
- Sport officiating technology
- known_for
- Electronic detection of hog line violations in curling
- developer
- University of Saskatchewan and Startco Engineering
- first_major_event
- 2003 Continental Cup of Curling
- adopted_by
- Canadian Curling Association (CCA)
Lore & Background
The rule governing hog line violations traces back to 1955, when Ken Watson's 'long slide' delivery prompted a revision to limit sliding. The rule evolved from curtailing at the tee line to limiting the slide to the hog line (1961), and finally requiring clear release by the time the stone reaches the hog line (1974). Both the Air Canada Silver Broom and the 1974 Macdonald Brier used the same 1974 rule. Human enforcement initially relied on the honour system, but officials were eventually introduced. Visual enforcement proved error-prone, with the onus on curlers to remove all doubts. Canadian hog line officials were originally at ice level, later moved above ice level, and returned to ice level in 1985.
Reader's Guide
The Eye on the Hog represents a technological solution to a long-standing officiating challenge in curling. Neil Houston played a key role in the initial development at the University of Saskatchewan. After testing at Sutherland Curling Club, the sensor handle made its high-profile debut at the 2003 Continental Cup of Curling, and the CCA quickly committed to using them for future events. Early on, curlers who insisted on wearing gloves during delivery were still judged by hog line officials, but eventually rules prohibited gloves to circumvent the sensor handles. There were rumours that some Manitoba tuckers had to adjust their deliveries. Notable incidents involving the technology include events at the 2011 World Men's Curling Championship (Sebastian Kraupp and Pete Fenson), 2015 Tim Hortons Brier (Carter Rycroft), 2016 World Women's Curling Championship (Amy Nixon), 2018 Olympics (Eve Muirhead and Ma Jingyi), 2020 Scotties Tournament of Hearts (Emma Miskew), and the 2021 Calgary bubble events. The technology's significance lies in reducing human error and controversy in enforcing the hog line rule, though it has not eliminated all disputes.
Did You Know?
- The Eye on the Hog is based on a patent filed by the University of Saskatchewan and developed by Startco Engineering, later acquired by Littelfuse.
- The first event using the 1974 hog line rule was the Air Canada Silver Broom; the 1974 Macdonald Brier still used the 1961 rule.
- At the 1986 Labatt Brier, hog line officials pulled 9 rocks in the first draw, including 3 by Mel Bernard.
- The sensor handle made its high-profile debut at the 2003 Continental Cup of Curling.
Frequently Asked Questions
What is Eye on the Hog?
Eye on the Hog is an electronic sensor-handle system used in curling to automatically detect when a player's stone crosses the hog line. It replaced the need for a human hog-line judge by embedding sensors directly in the handle of the curling stone.
Who developed Eye on the Hog?
The technology originated from a patent held by the University of Saskatchewan and was subsequently refined by Startco Engineering. Startco was later acquired by Littelfuse, which continued to support the product line.
Why was Eye on the Hog invented?
The hog line rule was introduced in 1955 to curb the increasingly popular 'long slide' delivery that Ken Watson had made famous and that younger curlers like Matt Baldwin and Stan Austman used as a showmanship trick. Electronic detection was needed to enforce the rule consistently without relying on a visible line judge.
When did Eye on the Hog first appear at a major curling event?
The system made its competitive debut at the 2003 Continental Cup of Curling, where it was used to monitor hog line violations in real time.
Is Eye on the Hog officially recognized in Canadian curling?
Yes. The Canadian Curling Association (CCA) adopted the sensor-handle technology as part of its officiating standards, making electronic hog line detection a standard feature in sanctioned competitions.
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