Speed Climbing Timing - Part 1 Sensors
02/19/2009 13:34 Filed in: IR Sensors | Speed timing
Most of my kids climb competitively and do an event called speed climbing. The name pretty much says what it’s about, but in general, 2 climbers go head-to-head on 2 25-50’ routes. After a climb is finished, they switch routes and climb again. The addition of the times of the two routes is the total time for the climber.
A problem that has plagued the event is the speed timing systems used are very unreliable. Most of these systems rely on some type of mechanical switch for the foot pedal and the top hand sensor to stop the clock at the finish, the top of the climber’s “lane”. Because the systems malfunction so frequently and can ruin the flow of the event and drastically extend the time it takes to execute the event due to re-climbing or fixing the system, I set out to design a system that did not use mechanical components. The goal is higher reliability, ease of installation, and also safety for the climber because sometimes mechanical switches have injured speed climbers hands.
Below is a video of a sensor concept I’m working on which will apply to the hand sensors at the top of the lane and the foot sensor at the bottom that’s used to detect a false start. These use an IR technology that’s relatively cheap (about $10 per sensor, 2 sensors per “pad.&rdquo
and immune to most IR emitted in ambient lighting situations.
The video demonstrates the concepts behind IR and how it might work for a non-mechanical speed timing switch. [Update: after several climbing events testing we decided to go with laser-based hand sensors which worked very well. IR was pretty good but not good enough for a timing system like this.]
The IR sensors I’m using are commonly used in robotics applications for obstacle avoidance and use the ubiquitous technique of modulating at a 38 kHz frequency to allow filtering of other IR sources from ambient conditions. The device is a GP2Y0A21YK from Sharp electronics and you can purchase these from Sparkfun in Boulder, CO.
The GP2Y0A21YK sensors have this voltage v distance profile (from the data sheet from Sharp Electronics):
There are other Sharp sensors in this same family that have different detection characteristics - ie: longer outer range and a sweet spot inflection that’s further away, but for a speed timing touch pad, and the empirical data, this sensor looks like it will do the job.
Speed Climbing Timing Part 1 - Sensors
Speed Climbing Timing Part 2 - Controller
Speed Climbing Timing Part 3 - Integration
Speed Climbing Timing Part 4 - Touch Pad Construction
Speed Climbing Timing Part 5 - Schematics
Speed Climbing Timing Part 6 - Perf Board
Speed Climbing Timing Part 7 - Display
Speed Climbing Timing Part 8 - Hand and Foot Sensors
Speed Climbing Timing Part 9 - Demonstration
Speed Climbing Timing Beta Test Boulder Rock Club
Speed Climbing Timing - Sensor Improvements
Speed Climbing Timing SHIPPED!
Speed Climbing Timing Schematics (shipped v1)
Speed Climbing Timing Installation
Speed Climbing Timing - Laser-based Hand Sensor Design
A problem that has plagued the event is the speed timing systems used are very unreliable. Most of these systems rely on some type of mechanical switch for the foot pedal and the top hand sensor to stop the clock at the finish, the top of the climber’s “lane”. Because the systems malfunction so frequently and can ruin the flow of the event and drastically extend the time it takes to execute the event due to re-climbing or fixing the system, I set out to design a system that did not use mechanical components. The goal is higher reliability, ease of installation, and also safety for the climber because sometimes mechanical switches have injured speed climbers hands.
Below is a video of a sensor concept I’m working on which will apply to the hand sensors at the top of the lane and the foot sensor at the bottom that’s used to detect a false start. These use an IR technology that’s relatively cheap (about $10 per sensor, 2 sensors per “pad.&rdquo
and immune to most IR emitted in ambient lighting situations. The video demonstrates the concepts behind IR and how it might work for a non-mechanical speed timing switch. [Update: after several climbing events testing we decided to go with laser-based hand sensors which worked very well. IR was pretty good but not good enough for a timing system like this.]
The IR sensors I’m using are commonly used in robotics applications for obstacle avoidance and use the ubiquitous technique of modulating at a 38 kHz frequency to allow filtering of other IR sources from ambient conditions. The device is a GP2Y0A21YK from Sharp electronics and you can purchase these from Sparkfun in Boulder, CO.
The GP2Y0A21YK sensors have this voltage v distance profile (from the data sheet from Sharp Electronics):
There are other Sharp sensors in this same family that have different detection characteristics - ie: longer outer range and a sweet spot inflection that’s further away, but for a speed timing touch pad, and the empirical data, this sensor looks like it will do the job.
Speed Climbing Timing Part 1 - Sensors
Speed Climbing Timing Part 2 - Controller
Speed Climbing Timing Part 3 - Integration
Speed Climbing Timing Part 4 - Touch Pad Construction
Speed Climbing Timing Part 5 - Schematics
Speed Climbing Timing Part 6 - Perf Board
Speed Climbing Timing Part 7 - Display
Speed Climbing Timing Part 8 - Hand and Foot Sensors
Speed Climbing Timing Part 9 - Demonstration
Speed Climbing Timing Beta Test Boulder Rock Club
Speed Climbing Timing - Sensor Improvements
Speed Climbing Timing SHIPPED!
Speed Climbing Timing Schematics (shipped v1)
Speed Climbing Timing Installation
Speed Climbing Timing - Laser-based Hand Sensor Design
asdfasdf
