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Here you'll find information about the project status and building instructions.
Have fun, and donate to a children charity (see license)
Marco Venturini - mv4wd
RC Hourglass is a project to develop a DIY automatic timing system that can be used in RC racing and other sporting events. The focus of the project is hardware design of the pieces of the system. The hardware is compatible with existing lap timing software.The project idea comes from two threads in RCTech.net forums about lap timing devices design by Howard Cano.The scope of the project is to simplify the design, document the building process and add new features.
The system is made of
- an active transponder, installed in every car. The circuit is usally battery powered by the ESC or battery in the model. Every transponder sends out a radio signale that contains a unique number.
- a detection loop, on the track. This is simply a loop of wire fixed on the finish line of the circuit, either on the ground or above the track.
- a loop amplifier. It's a small circuit located at the loop, that connects to the decoder with a coax cable (like sat TV cable).
- a decoder. It's a USB interface between the loop amplifier and the computer. The purpose is to decode the radio signal and identify the passing transponders. This information feeds the timing software. The decoder can be also used as a PIC programmer for the transponder chips.
- a computer with a timing software. The computer reads passing timestamps and transponder numbers from the decoder. The timing software records lap times and decides who wins the race.
Transponder and decoder build instructions are published in the wiki.
The project is in beta testing status as features are added/tested. Several prototypes of the decoder have been tested succesfully. Many transponder prototypes have been tested successfully.
RCHourglass Manager software is available for decoder configuration and RC4 transponder detection
Beta 3 firmware has RC4 detection, AMBRc protocol emulation and beeper/led notification.
Beta 5 firmware has a better AMBRc protocol emulation, TranX emulation, a second serial port management useful for Arduino (and others) integration, PIC programming with no additional hardware.
Beta 6 firmware correction on serial protocol mode selection.
Beta 7 firmware corrects transponder number decoding causing numbers above 9.999.999. AmbRc protocol parsing relaxed for broader compatibility.
Beta 8 firmware corrects passage record format on serial port
Beta 9 Corrects SET TIME parsing, AMBRC passage time format for milliseconds < 100 and avoids LEARN feedback on both serial interfaces
Beta 10 Corrects interface reverting to CANO mode after LEARN (regression in beta 9)
The RCHourglass transponder should work with CANO decoder and AMB/Mylaps decoders unless they're updated to the latest firmware.
Check the Compatibility chart for more details.
The decoder can detect RCHourlass, AMB, MRT, CANO and RC3 transponders. RC4 transponders can be detected after registration in the decoder memory.
The decoder is compatible with lap timing software using the CANO protocol (Z-Round and Flipside racing) A serial AmbRc emulation mode is available, making the decoder compatible with most of the timing software.
See the detailed licensing terms in the GitHUB repository main page. Basically no commercial use license is granted, and you are kindly requested to donate in charity a small sum if you find the project useful. Any derivative work source code/design must be public and use this licensing terms.
RCHourglass Project - Marco Venturini - mv4wd