As I was drafting the previous post, this popped into my mailbox. It resolves a few questions, more so than the previous RTA email, in fact
Subject: RE: Bike lanes, traffic lights, police operations and RTA guidelines
Hi Jason
The Lord Mayor has asked me to reply to you directly on this issue. I'm also available to speak to you in person if you'd like to discuss in detail
You've raised quite a few issues, and I know John at RMS has replied to you though you feel not all questions are fully answered. So I'll try here, and you can let me know if you want more detail on any of these, or if I've missed anything.
1. Induction loops, carbon fibre and aluminium bikes, and drainage grate lids
The induction loop electical field detects overhead conductive (not just ferrous) material. It will detect a bike with a carbon frame if it has aluminium rims. The detector "learns" about nearby static metal such as the pit lid, and will ignore it.
2. Passing over versus staying put on the loop
Just before each phase change, it checks to see whether the loop detects the presence of a bicycle (at that actual time) and if so, will allocate a green light in the phase. So you do need to stay on the loop until it does the check. We have recently double checked all the loops on Union Street, and all work if there is a bicycle in the loop at the phase check time.
3. Location of the loop
As you point out, many riders pull over to the left kerb to rest their foot on the kerb, putting them outside the loop area. To better match the infrastructure to the behaviour, we are doing three things:
(a) RMS have increased the sensitivity of the loops to the maximum setting, so that detection should now extend to slightly outside the loop itself;
(b) some of the loops have already been recut to put them as close to the kerb as possible and made wider to provide a wider area of detection, and more will be extended;
(c) RMS will investigate using a new overlapping loop system to extend coverage, though this hasn't yet been tested fully.
Let me know if you want more information, and thanks for spreading the word on the diamonds and how things work - it's helpful.
Regards
Fiona
Fiona Campbell
Manager Cycling Strategy
City Of Sydney
posted @ Wednesday, March 21, 2012 12:51 PM