DrJB

This could not be farther from the truth. Some worm drives ARE reversible (such as those operating the tray of DC/DVD/BD drive. However, MOST worm drives are NOT reversible. The simplest driving factor is the relationship between the friction angle (tan mu) and the angle of the helix making the worm gear. For the gear drive to be 'reversible, you need: Helix angle > mu If the above relationship is NOT satisfied, then you'll enter a 'lock-up' and no matter how much lubrication you add.

The date on my computer says 16-May ... Thanks to Jim, the coming two weeks will be the longest ever . Here is an idea, why don't you put a count-down on the front-page?

In principle there should be two options to 'synchronize' motions of two mechanisms driven by gears. 1. Make sure the gear ratio is fixed and there is no 'drift'. 2. Have one mechanism 'trigger' the other. Option 1 is rather simple. For option 2, it should be feasible to trigger the arm (up motion) when the cart for example is at 75% of its travel down the slope. I think in this case, where synchronization needs not be very precise, the second option is viable. Of course, the devil is in the details as they say, and I can't think (for now) of a mechanism that does that.

Interesting. I thought caster angle increases self-aligning torque and thus steering stability. I need to revisit my vehicle/tire dynamics books.

I found the LDD file I was working on a while back. It's not final, and not tested. Also, the bucket part is not available in LDD so I used close substitutes. I have yet to build this and try it ... as I already have all the parts. http://www.brickshelf.com/gallery/djamil/GBC/bucket_wheel_excavator3.lxf

I recall reading somewhere that they came up with close to 300 new sets for 2016 so, ... not sure the 'number of themes' metric is very valid.

True, but those balls are now as expensive as anywhere else. Close to $1.00 a piece.

Sometimes silicone grease does wonders ... I've learned that from an old hobby of mine: saltwater fish tanks.

If I recall, it works when you suddenly brake, as if the momentum of the whole assembly gets transferred o the battery box only. I need to rebuild mine and re-visit the dynamics (Newton's 2nd law).

It might be easier if you used the DB gears. The problem with cardans is that the speeds will vary. Do you need ALL axles to be rotating in the same direction or is it ok if they alternate? If so, how about the example below? INcidentally, I started a thread few days ago about using gears in other angles than 0/90 degrees. This is one such example.

I was secretely hoping the upcoming Porsche to have the suspension I showed in the first post. Regrettably, it won't

Yet another manifestation of ... reliability and complexity do no go hand in hand.

+1 I was really hoping for a multilink ... need to give them few more years, as the current parts have way too mch slack in them and a multi-link with such parts would be rather wobbly.

This sounds like what they did on a GM Truck few years ago ... Silverado I think, but could be wrong.

The wheels are spinning, but the Porsche logo in the middle is NOT ... hmmm, I wonder how they can do that.

Get the two below ... Fun builds that'll last hours. Of course, if you like the 42009, you should get it ASAP as it's nearing the end its production cycle, and prices WILL go up. The two below will give you a taste of all modern Technic has to offer: Power functions, pneumatics, tracked vehicles, neat suspension ...

I think it's the one in yellow, below

You need to add the modules from philo (www.philohome.com). Philo started the GBC craze long before Akiyuki.

Didn't the 8880 use 8 springs total, 2 per tire? Then there is the Unimog, which was heavy, so they used STIFFER (fewer coils) springs instead.

Take a look at Nico's Citroen 2CV suspension. Springs are positioned horizontally! http://www.eurobricks.com/forum/index.php?showtopic=59250&st=200 I did an LXF some time back, try it out: http://www.brickshel...ry.cgi?f=537067

That is exactly my thinking. Doing a current/torque curve might be a bit difficult (especially due to damping/friction), but doing 2 key measurements (stall vs. no load) should be sufficient.

1. My apologies, did not intend to be 'lecturing' ... 2. Thank you for sharing, very interesting. I also have interest in Arduino and Raspberry PI ... working on building an IMU (Inertial Measurement Unit) now. 3. Agree, not sure why values are so small. Hopefully Philo can see this and give his opinion.

Not to digress but the numbers seem low. To measure current, you need to 'break' the circuit and connect the motor 'in series' with the multi-meter. This is not an easy thing to do with the PF connectors. Have you tried comparing your numbers against philo's ?

Agreed, I usually try to avoid that but, forgot this time. Cheers

Correct, it is a double wishbone, but in contrast with the 'classical' WB, this one has the spring and damper in very 'unique orientations, most likely because of limited vertical space (I know there are other reasons). This is very interesting, I may have to build it to understand how it fully works.