Daktronics RTOP

The Daktronics RTOP (relay take-off platform) is a family of starting-block platforms made by Daktronics, Inc., of Brookings, South Dakota, that sense the instant a relay swimmer’s feet leave the block. The platform reports the departure to the OmniSport 2000 timing console, which compares it with the incoming swimmer’s touchpad finish: a positive difference is a legal exchange and a negative difference an early one.¹ Unlike the mechanical platforms of other makers, the RTOP detects the swimmer capacitively, sensing human contact rather than pressure or force, an approach Daktronics patented in the 2000s.²³ Shared background on how relay exchanges are judged and ruled on is in the relay take-off platforms overview.

Daktronics lists the RTOP both on an active support page and among its discontinued product resources, so a facility may encounter it described either way.³⁴

Design and construction¶

The platform is built around a capacitive sensor mat: electrodes in the mat hold an electric field that the swimmer’s body influences, and the electronics detect the change in capacitance when the body leaves. Daktronics’ patent (US 7,403,135, by Kurt R. Kaski, Allen J. VanBemmel, and Jason C. Warne; priority December 2003, granted July 2008) describes automatic recalibration that separates the swimmer’s presence from environmental drift, and its background section states that earlier force-measurement approaches were limited to an accuracy of about plus or minus 0.03 seconds.² Because the reading is capacitive rather than mechanical, Daktronics states the platform is not affected by loose or vibrating blocks, the weight of the swimmer, or hop starts; on a hop start the platform reports every departure and the console judges the exchange from the last one.¹ The same principle is why Daktronics advises against a towel on the block: material between the swimmer’s skin and the platform can make it trigger early.¹ The Colorado Time Systems RJP, the other United States platform, instead registers the mechanical unloading of its top and leading edge.⁵

The platform itself is lightweight plastic, with a bend that faces the pool and a gray electronics box on the underside carrying a red status LED and two AA batteries. The LED flashes when the platform is working; a solid or dark LED means the batteries need replacing, which Daktronics schedules before each meet and roughly every two days of competition or 20 hours of use.¹ The console also reports on the platform: the letter R appears on the lane’s LCD when the platform’s batteries are weak, and disappears entirely when they are dead.¹

Exchange judging and the zero point¶

Every manufacturer defines its own zero point for the exchange differential. Daktronics states that there is no manufacturer’s tolerance to set on its RTOPs: its FAQ gives an exchange of 0.0 seconds or higher as safe and minus 0.01 or lower as a disqualification.¹ This differs from the fixed 0.01 second that Colorado Time Systems adds in favor of a safe take-off and the minus 0.03 second tolerance reported for Omega equipment; the relay take-off platforms overview covers how governing bodies defer to the manufacturer on this point. Daktronics states the RTOP meets and exceeds the requirements of the NCAA, USA Swimming, FINA, and NFHS, while noting that such bodies write rules rather than approve equipment; these are the company’s claims.¹ Its brochure likewise describes the RTOP as the most accurate in the industry, which is a marketing claim.⁶

Connection and use with the OmniSport 2000¶

The platform’s dual banana cord plugs into a button jack on the lane’s deck cabling, typically button 3 on the lane module (on-deck) or deck plate (in-deck); the connectors stack, so where a lane uses all three backup buttons the RTOP piggy-backs onto a button plug. Daktronics recommends dedicating button 3 to the platform so the console setting can stay fixed.¹ On the console, the relay take-off menu sets the platform type (button or Daktronics), the button input used, and an arm time, the window between the touchpad time and the platform time within which a departure is treated as the exchange; Daktronics suggests 0.8 seconds.¹ The console needs firmware version 8.3.27 or newer to operate the RTOP, and the Pro Swimming software (version 1.1.18 or newer) exposes the same settings from its configuration dialog.¹

During relay events the console times the exchanges and prints each one with the race data: the race log marks platform departures with an R by length and lane, start-reaction times with an S, and the results printout lists the exchange differential for each leg.¹ In individual events the console ignores the platforms for everything except the start reaction time, and events with in-water starts produce no reaction times.¹ The pre-session test is built into the platform: with the RTOP connected its red LED flashes, and placing a hand flat on the surface for two seconds and pulling it away turns the LED solid for about a second before it flashes again, while the times appear on the console printouts.¹⁷

Daktronics platforms work only with Daktronics equipment, but the console reads more than one vendor’s platforms. Daktronics states the OmniSport 2000 can read Swiss Timing Omega platforms and starting blocks through an Omega platform setting, while a Daktronics RTOP does not work with a Swiss Timing Quantum or Colorado Time Systems console, and a CTS platform does not work with the OmniSport.⁸¹

Mounting¶

The platform straps to the starting block with a cam-buckle strap on each side, pulled snug with no twists, the electronics box flat against the bottom of the block and the excess strap tied up out of the splash. Before each session the operator inspects the platform for cracks, verifies the sticker covering the LED and the cable strain reliefs are intact, checks inside the electronics box for water and a sound gasket, and cleans any corrosion off the banana plug with the console’s maintenance kit.¹

Training use¶

With a Daktronics pace clock the platform doubles as a training tool. Connected to the pace clock’s platform jack (program 11) together with a touchpad, the clock displays each relay exchange time; connected with the HS-200 Horn Start, it displays the reaction time from the start tone to the swimmer leaving the platform.¹⁶

Care and maintenance¶

The platforms are stored dry, with cables unpinched, surfaces free of debris, and not resting on the platform lip; Daktronics recommends its optional storage cart, which the brochure lists as carrying up to 12 platforms.¹⁶ If a platform stops working, the manual’s checklist runs: replace the batteries, inspect the cable, inspect and clean the banana jack, try another lane module or deck plate, and then contact Daktronics.¹

Models¶

Daktronics catalogs six sizes to fit different starting blocks; all are 0.5 in (13 mm) thick.⁶

Model	Dimensions	Weight
RTOP-2020	19.7 × 20 in (500 × 508 mm)	8 lb (3.6 kg)
RTOP-2220	22 × 20 in (550 × 508 mm)	8.5 lb (3.8 kg)
RTOP-2420	24 × 20 in (600 × 508 mm)	9.1 lb (4.1 kg)
RTOP-2023	20 × 23 in (508 × 584 mm)	9 lb (4.1 kg)
RTOP-2723	27 × 23 in (686 × 584 mm)	11 lb (5 kg)
RTOP-3223	32 × 23 in (813 × 584 mm)	12.5 lb (5.7 kg)

Specifications¶

Sensing	Capacitive sensor mat with automatic recalibration
Timing accuracy	1/100 second
Exchange zero point	No manufacturer tolerance; 0.00 s or higher legal, minus 0.01 or lower early
Construction	Plastic platform; gray underside electronics box with red status LED
Power	Two AA batteries; about 20 hours or two competition days
Thickness	0.5 in (13 mm)
Mounting	Cam-buckle straps, one per side
Connection	Dual banana plug, stackable, into a lane button jack (button 3 typical)
Console requirement	OmniSport 2000 firmware 8.3.27+; Pro Swimming 1.1.18+
Training controller	Daktronics pace clock, platform jack, program 11
Cross-compatibility	Not usable with CTS or Swiss Timing Quantum consoles

See also¶

• Relay take-off platforms: the shared overview, including how exchanges are judged and the governing-body rules
• Colorado Time Systems RJP: the mechanical platform from the other United States manufacturer
• T-7000 Series Touchpad: the finish input the exchange is judged against
• Daktronics Pushbutton: the backup button that shares the lane’s button jacks
• OmniSport 2000: the console that computes the exchange differential
• HS-200 Horn Start: the start system used for reaction-time training
• Equipment: the equipment reference

References¶

Footnotes¶

1. Daktronics, OmniSport 2000 Timing Console Operation Manual (ED-13312, Rev 16, 23 May 2019), section 9, Relay Take-Off Platform. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸

2. Google Patents, US 7,403,135: Capacitive relay takeoff swimming platform sensor system (Daktronics; Kaski, VanBemmel, and Warne; priority 22 December 2003, granted 22 July 2008; sensor-mat capacitance, automatic recalibration, and the prior force-based accuracy limit). ↩ ↩²

3. Daktronics, Relay Take-Off Platform support (senses human contact rather than force; not dependent on the athlete’s weight). ↩ ↩²

4. Daktronics, Aquatics RTOP discontinued-product resources. ↩

5. Colorado Time Systems, Relay Judging Platforms for Competition (the mechanical top-and-leading-edge sensing of the competing platform). ↩

6. Daktronics, Aquatics Solutions brochure (DD1565872, Rev 07, June 2018), pp. 7 and 13 (model table, storage cart, training use, and the accuracy claim). Print document, not hosted online. ↩ ↩² ↩³ ↩⁴

7. Daktronics, How do I test Relay Take Off Platforms (KB DD2199844) (hand-flat test and LED behavior). ↩

8. Daktronics, Which RTOPs, starting blocks, and third-party timing systems are compatible (KB DD2090313) (OmniSport 2000 reads Omega platforms; Daktronics RTOPs incompatible with Quantum and CTS consoles). ↩