DIY Seatbelt tensioner with simtools

[HoiHman]

A lot guys that have build the SFX100 are thinking about adding a seat belt tensioner to their rig.

Even though i would have prefered to use one the SFX100 servos doing the work, i have decided to order the parts servo seatbelt tensioner and will start building as soon as the parts arrive.

Parts needed:
Servos
https://hobbyking.com/de_de/turnigy...-servo-33kg-0-21sec-154g.html?___store=de_de1

Turnigy 5A (8-40v) SBEC für Lipo :
https://hobbyking.com/de_de/turnigy-5a-8-40v-sbec-for-lipo.html

Aduino uno
https://nl.aliexpress.com/premium/a...SB_20190116083039&origin=y&catId=0&isViewCP=y

Power supply:
Still need to order one, or if the specs of the servos allow it, i will use the 6v power supply of my GS-4

I will be copying the build from @Ringorian and @saxxon66 who have already a topic with complete instruction on the german forum.

https://forum.virtualracing.org/sho...ffer-100-Euro-(auch-Ohne-Motion-realisierbar)

Jochen en Micha, feel free to jump in and educate us

 

[wajdi]

Took about 5 different methods to get it down there, too.

Try it, you'll never go high again.....

Ok, but is one bracket per side enough strong to anchor the actuator to the rig?

 

[Mascot]

Ok, but is one bracket per side enough strong to anchor the actuator to the rig?

One bracket per side is DEFINITELY not enough. Anton has hidden brackets on the top of the chassis side-rails too, I believe.

 

[anton_Chez]

There are as Mascot says. I had 2 per side, but ran out of room to keep the 4 side mounted, so I have 2 mounted sideways and 2 more on the inside of the actuators connected to the top of the main rail.

If I couldn't have done this, I probably would have tried to knock up some plates to still give the surface area contact but be able to raise the bottom of the actuators independently of the available slots. It's super good being like right in between the tyres.

Had my first race with the Sparco Rev and the anchored lap straps, this time with a proper mount.

You can feel A LOT with this. Still need to do some more testing to see whether I actually like it or not, but I tell you, you flax the whole race when the belts tighten on you. I'll have to try the shoulder ones now.

Once again, I've talked myself into, out of, into and out of again an active tensioner! This guy needs to take my money before I change my mind again!

 

[Steve D]

There are as Mascot says. I had 2 per side, but ran out of room to keep the 4 side mounted, so I have 2 mounted sideways and 2 more on the inside of the actuators connected to the top of the main rail.

If I couldn't have done this, I probably would have tried to knock up some plates to still give the surface area contact but be able to raise the bottom of the actuators independently of the available slots. It's super good being like right in between the tyres.

Had my first race with the Sparco Rev and the anchored lap straps, this time with a proper mount.

View attachment 294015

You can feel A LOT with this. Still need to do some more testing to see whether I actually like it or not, but I tell you, you flax the whole race when the belts tighten on you. I'll have to try the shoulder ones now.

Once again, I've talked myself into, out of, into and out of again an active tensioner! This guy needs to take my money before I change my mind again!

Very neat and minimalist floor mounted solution there mate! I like a lot! Have you attached that angle to those ex-triple monitor mounts you placed under the feet? (One thing I've quickly learnt with this hobby is never never throw anything away!!)

 

[anton_Chez]

Took those mounts away completely once I put the angle there. No need for them. I've got the harness anchors bolted directly to the angle. I tried to route the belt and angle the anchor as best I could but the path through to the seat is not completely perfect. It's still OK though. I've just put the shoulder straps into that center hole. I'm going for a test drive now....

 

[Mascot]

OK. 4-point harnesses.
What's considered 'best', easiest, most comfortable?
The 'all-four-straps-into-one-camlock' version thus:

...or the single seat belt-type closure?

I imagine the second type is quicker to get into/out of and maybe more comfortable as the shoulder straps stay parallel instead of converging on your toilet parts... but the cam lock version looks undeniably cooler.

Much difference between the two re ease and comfort?

 

[Steve D]

OK. 4-point harnesses.
What's considered 'best', easiest, most comfortable?
The 'all-four-straps-into-one-camlock' version thus:

...or the single seat belt-type closure?

I imagine the second type is quicker to get into/out of and maybe more comfortable as the shoulder straps stay parallel instead of converging on your toilet parts... but the cam lock version looks undeniably cooler.

Much difference between the two re ease and comfort?

Despite the extra cost, go for the 'aircraft style' (first option) Steve and ensure 3" straps all round. The other design will typically be 2" (possibly with 3" spreaders included) and whilst they definitely do a job and the 'buckle set up' is quick and simple, (I used them for years in a Westfield), the wider straps can offer you a little more comfort and spread the load better when tightened.

Also the clip on fittings are probably easier to work with than the bolt-thru version in terms of using eye bolts and being able to remove each strap quickly, should you need to.

Also make sure you get a saloon / rally car version and not one suited for a Caterham / Westfield etc as the straps are shorter due to the considerable lack of cockpit space and the very close proximity of the mounting points.

Plus and most importantly, you really do want to look 'the nuts' and if you are going to be laughed at by onlookers, you may as well be ridiculed at least looking the part!

 

[Mascot]

Thanks @Steve D, sage advice sir.

 

[o Tiger Feet o]

View attachment 293852

Hi, Just wondering why the alu profile with the springs doesnt lift from the floor? Surely its not 'bolted' into the carpet?
Or is that black 'matting' actually solid too? (It looks like rubber to me?)

Thanks

 

[o Tiger Feet o]

Just to add, I made a passive type for my V3 using bungee cords... It didnt look great in its prototype state but it worked pretty damn well imo. Im sure once you have the correct spring it would be a better solution all round.

 

[anton_Chez]

Funnily enough the harness has a very purposeful job especially on a motion platform, despite how silly it might look to someone who probably can't drive anyway.

I always feel more connected to the car / sim with the harness on. I feel like I should have it on when I can't be bothered to strap myself in. I've ordered some shoulder strap pads for mine, too. I think they will certainly make it more comfortable when wearing only a t-shirt in the warmer months. The buckles and edges of the straps can dig into you. It will probably help more now too with adding a bit of padding when the harness is tensioned through out newly fixed mounting points.

 

[anton_Chez]

The piece of profile that the springs are connected to is bolted to the sheet from the underneath. That's a metal sheet spanning the width of the chassis that the actuators sit on. Not sure if aluminium or steel but it's metal. Above the carpet.

 

[o Tiger Feet o]

That's a metal sheet

Thanks, I guess it had to be really To my eyes it just looks rubbery

 

[anton_Chez]

I think it's checker plate.

However you spell it.......

 

[Steve D]

Thanks, I guess it had to be really To my eyes it just looks rubbery

PMSL!! Brilliant!!.

As Anton says it's a metal sheet. (4.5mm aluminium kicker plate)

I wanted to use kicker plate because apart from looking pretty neat and tidy, it offers really good resistance to the anti-vibration material that form the base of the feet I made. No movement or slip at all when I'm running the actuators at higher intensity levels.

 

[sjb266]

How are so many people ordering / receiving the GS-5? I can't find it on their website??

You need to email them and they enable your account to place an order.

 

[sberns]

I’ve been following the sfx100 thread and this one for a while. I’ve got a SimX stage series seat mover, Diy Simwind, Seattime’s active tensioner (which is fantastic BTW) and a DIY G-seat insert. For those of you looking for an alternative to a GS-5, the G-seat insert that I built is a cheap alternative (those not as robust) but easy to build, uses Simtools and definitely gives fantastic feedback for sustained Gforces in the corners. Thread is here (shopping list on page 2):
https://www.xsimulator.net/community/threads/g-seat-addon-to-3dof-rig.11260/

BTW, I’m thinking of going ahead with the SFX build and bolting them onto my seatmover for the heave/pitch effects that I’m missing. What do you guys think? I’m a bit concerned about the rigidity of the frame but I figure if I remove the TL component and maybe add a floorboard it should be ok.

 

[metalnwood]

I moved the mounting point for the shoulder harness in my passive setup from behind me at the same level of the holes in the seat to vertically down and it has changed the feel markedly. Not in a good way either. I now know what you mean by it pulling down on the top of your shoulders rather than more on your chest.

Now I have to fix that! Getting closer to the most awesome rig I have owned lol

 

[Chris_I]

In my rallycross car I had my seatbelts in an angle of 60 vertically down which held me down in the seat very well but wasn't nice on the shoulders. When starting to use a HANS system I had my rollcage modified to have the seatbelts attached to it in a more horizontal way and that was much better in use and comfort.

Soo purely on comfort I would suggest to have them more horizontal.

 

[anton_Chez]

I wonder how I can achieve this with nothing behind me to mount the harness more horizontal? I could have some profile mounted to guide it better, but I'm not sure that will work as good as just having them the way you had before, metal, or look very nice either. I don't worry THAT much about aesthetics, but now that the V3 is gone, the new seat going in, the monitor removed and the rig basically dropped on its ass, it looks quite mean..... I like it.

I am still waiting for a payment notice for my tensioner, SeatTime seems to be MIA. Hugo, too..... Might have to drop him a message and see what's up with it. I know he takes some time building them and with a little backlog it will likely be months before I see mine. I wonder how this active tension is going to feel with the straps going straight down behind the seat? I don't have much issue with it static. I've put the shoulder straps back on the moving chassis and re positioned the lap straps on the fixed metal angle using the springs I removed from the shoulder harness experiment. I think this way actually works nicer. You can feel the belt tighten on your waist slightly (not harshly because the springs are not very tight and the straps now have some play as opposed to being bolted straight to the angle) but not in a way that affects your driving. It's super subtle but when braking for a hairpin you definitely feel it. The race I did with them fixed but not with springs it was pretty harsh, the pulling and releasing was very noticeable and kind of distracting.

Also, if you do this and don't want to be cut in half, buckle and tighten your lap straps AFTER the platform is raised......

A friend told me to pass that onto anyone considering fixed point lap straps......