Radio controlled road vehicles on Upper Benllech

[Giles]

That really takes the biscuit..... a bit of a Faberge egg compared with my blacksmith approach!

 

Stunning.

[otherplanet]

Fabulous as usual.

 

In the comparison of the response of the steering the Model T seems to have a lag. That could make control more difficult rather than easier.

 

Out of curiosity, what space is available for a receiver - W x L x H in mm?

 

And have you any interest in writing your own program for the receiver?

 

...R

Thank you Robin

 

The lag is more to do with the backlash in the mechanism, the motor starts turning straight away, just at a lower speed.

about halfway through the video, I tightened the joints in the steering, which made a small improvement.

However, the biggest issue when driving is over steer, the wheels turn further than you expect and before you know it, you are veering off the road.

 

 

The space is about 25 x 14 x 3 maybe a smidgen more thickness as this is traded against battery thickness.

 

Whilst i have dabbled with software for work, it is not something I have really got into. I have a copy of python for dummies on my book shelf, which I have still not got around to reading since I received it many years ago. 

Thank you.

 

Are you thinking of the atmega?

[otherplanet]

It's not real you made it all up didn't you!

 

Incredible.

 

How about animating that 'orse

Aha, you've got me! 

 

Thank you

 

Every so often my brain turns to thoughts of how to animate a moving 'orse and then thankfully it runs away to think about something else. Maybe its time to go there again.

[Robin2]

the biggest issue when driving is over steer, the wheels turn further than you expect and before you know it, you are veering off the road.

That is the problem I was setting at the feet of "lag". Faster servo response might actually be better

 

The space is about 25 x 14 x 3 maybe a smidgen more thickness as this is traded against battery thickness.

 

Are you thinking of the atmega?

It is possible to program the Deltang devices that use Atmega 328 chips using the Arduino IDE. It's a bit fiddly because the board is so small.

 

I have also started experimenting with ESP8266 devices which have WiFi and a microprocessor on a very small board - but it would need to be supplemented by a motor-driver chip. It should be possible to write a small program for a smart phone to allow it to act as the controller.

 

Thinking more about your steering "problem" I suspect your idea of using a TX control potentiometer that is less sensitive may be the best, and simplest solution.

 

...R

[Pikey]

World class 

[otherplanet]

I have been trialling different road surfaces for running the RC vehicles on.

The industrial estate videos show them running on printed paper and Upper Benllech uses plaster based roads, which the Atkinson and Scammell cope well with except for a couple of particularly steep / rough sections.

However for the new layout I want to represent pre WW1 roads, unmade roads and even mud.

 

But I still want the trucks to run reliably.

 

So I have been trialling a short section of road surface.

Starting from a base of foam board. The idea was to create something that could easily be tilted to test inclines and represent diverging paths in the mud.

 

I trialled chinchilla dust, this gave a good structure, but the surface was so sharp, the wheels did not get a good grip.

 

I also tried coating this with Plastidip silicone paint, which has provided improved friction on the wheels, but did not appreciably improve the chinchilla dust road surface. 

I then tried tiling grout, this provided a better surface, however it took a couple of attempts to make surface features which were not so over scale as to create an obstruction.

So far tiling grout, with ruts created with paint brush and running spare wheel sets through, seems to give the best surface, which the Atkinson and the Model T can both cope with, even with a small incline. The model T does tend to stall its motor when it hits too steep a feature, whereas the Atkinson runs out of traction and spins its wheels.

 

 

On another matter.

I gave in to temptation and ordered myself an FPV camera from China.

Its designed to fit onto these very small drones that are available for sub £20

It includes camera and transmitter, and then a receiver plugs into the micro USB port on my phone, which slots into a cheap Virtual Reality Headset.

 

I was able to get the camera and receiver to connect very quickly and easily, whilst the phone worked no problem once I had found the correct App to download.

 

I then knocked up a temporary mounting that fits where the cab normally goes on the Atkinson.

This places the camera about the right position for the driver, with the chimney encroaching into the left side of the view.

I added a roof as it secures the top of the camera and stops the wobbling.

This is just a temporary setup to try things out. I don't intend to leave the camera in the Atkinson, rather to build a new vehicle to take it, with a nice large body to hide the electronics and the battery.

 

I have to say though I am really impressed. the view is amazing, the software divides the screen in two, so you get an image for each eye. whilst its not 3D, it is still very immersive, and I found it very easy to assess distances and drive through quite tight gaps.

 

Having dreamt of being able to walk through my layouts for over 20 years. This is by far the closest I could ever imagine to that experience. I know that many people have fitted cameras to model locos, including live feeds in loco cabs. Many of which look amazing. But the ability to control and manoeuvre left and right as well as speed is quite a revelation.

 

The software also allows a video to be recorded, so here is a short clip.

 

 

 

[19Ted54]

Geoff,

 

once again, a phantastic achievement! Could you please give us some hints (and links) to the camera, receiver et al...

 

Maybe one or two more photos of the Atkinson would be great, not only the camera but also the steering gear and its servo!

 

I take it that the new, bigger vehicle will be a period vehicle, or?!

 

Greets from Austria, Eduard

Edited May 12, 2019 by 19Ted54

[otherplanet]

Thank you

the Camera and receiver came from banggood.

I have not used them before, but a collegue at work bought a similar setup for his drone, so I thought is was worth a try.

The camera and transmitter is all in one.

https://www.banggood.com/5_8G-48CH-25mw-Transmitter-700TVL-120-Degree-Wide-Angle-Wireless-FPV-Camera-NTSC-p-1166067.html?rmmds=detail-left-hotproducts__2&stayold=1&cur_warehouse=CN

 

It was the smallest integrated set with a wide range of channels on the 5.8GHz frequency range.

It is low power at 25mW to maximise endurance, i dont expect to need the range. I choose the dipole aerial as it is much smaller and again, in a model railway context, I dont think I need the extra performance of the cloverleaf. All of these are assumptions to be tested.

 

The receiver came from the same site.

https://m.banggood.com/Eachine-ROTG01-UVC-OTG-5_8G-150CH-Full-Channel-FPV-Receiver-For-Android-Mobile-Phone-Smartphone-p-1147692.html?rmmds=search

and plugs straight into my android phone. Using the FPV-GO software they recommend.

This combination was reviewed somewhere as being compatible. I wanted a set that would definitely work so that I could learn from it.

 

The phone clips into this headset,

bought from ebay some time back to watch 3d videos on youtube. there are some superb videos on youtube from the German 1:87 RC guys who have placed 360 cameras onto a layout, and you can turn your head to look all around and watch the vehicles go past.

If you search on your shopping website of choice for google cardboard. you will find a range of headsets from less than £10 upwards. It appears to be worth looking for the ones with high quality lenses.

With the phone set to dual image mode, it displays a pair of images to line up with each eye.

 

My original plan was to build it into this,

.

 

bought for me as a birthday present.

Its a pre WW1 subsidy truck, The british government offered significant tax subsidies for business which purchased vehicles that complied with certain specifications from the war department, the downside being that they had to be kept in good condition, inspected once a year and made available to the war office if hostilities broke out. I believe other European countries had similar schemes.

Consequently, these vehicles, produced for the military modellers are also useable for civillian applications. (although I think the Dennis was technically only just into production in 1914)

I am very impressed with the kit so far, it has lots of details and the resin appears to be well cast, although there is a lot of flash.

The plan is to use the canvas tilt to hide all the extra stuff, and initially I intended to cut holes in the tilt and the cab to poke the camera through. but the lens is much larger than I anticipated. So I may have to rethink.

 

But that is kind of what I am expecting. Hence the temporary mount for the Atkinson, to try things out, see what works and what doesnt.

I am thinking to try some of the button hole cameras, which are much smaller, but don't have the transmitters etc. This way I can try replacing one bit at a time to see how things go. with reasonable confidence I can go back a step when I break something.

 

In the mean time, I have started CAD work on a working transaxle to replace the one from the kit. With the plan to complete an evolution of the model T Chassis that just has the servo end, to create a very compact servo.

 

All plans at the moment, little things ticking in the brain whilst I experiment with stuff for the layout.

The road surface worked well until I painted it, whereupon the smooth parts of the grout went very glossy.

Despite the use of matt paints and then subsequently applying matt varnish, the whole surface looks increasingling waterlogged. I want it to look like it rained a few hours ago, with puddles in the ruts. but this is way too much. So work still to do.

[otherplanet]

Geoff,

once again, a phantastic achievement! Could you please give us some hints (and links) to the camera, receiver et al...

Maybe one or two more photos of the Atkinson would be great, not only the camera but also the steering gear and its servo!

I take it that the new, bigger vehicle will be a period vehicle, or?

Greets from Austria, Eduard

The Servo is off the shelf from Micron radio control. Although the same basic unit is available in lots of other places. It is half buried in the rear of the boiler, which had the back cut away to make space.

 

Underneath, the steering knuckle is an earlier evolution of my Romford crankpin based design. using the squared off larger screw as the main block, with a hole drilled for the kingpin and the steering arm soldered to the sides.

The Axle is from square brass box section, cut and soldered to make a shallow U to clear the servo spindle.

The track rod, made from 2 pieces of brass rod bent into L shapes, has grooves filed into the bent up ends. the steering arms are bent into loops at the end, hooked over the filed grooves and the tightened to lock onto the ends of the track rod. a short piece of brass sleeve allowed the tracking to be set accurately. Finally a pin is set perpendicular to this sleeve to engage with the servo horn.

The standard horns being far too long. so this was made by drilling through the servo spindle and then inserting a piece of wire with a loop bent into it.

 

Finally a shot of the tail hook, which is operated by a piece of SMA wire

[Pikey]

Re: traction - I'm making an off-road experience type diorama to drive a Land Rover Defender around, and after using DAS clay to make a few hills I found the tyres didnt have any grip. I've had a good result creating textured paint with some ordinary cheap (brown) paint, polyfilla and sand all mixed together. Now I can even drive up the really steep bit that I put in only to be driven down    

 

Its roughly 1 part polyfilla, 2 parts paint, 3 parts sand - although I wanted a rough muddy hillside sort of finish rather than a road.

[otherplanet]

Intriguing. I presume that is in OO?

Is the landrover an Oxford diecast with rubber tyres, or have you improved on them too?

Muddy ground is good as I want a combination of metalled Road, unmade Road and cleared land.

Sounds like something to make a comparison with.

Do you have any pictures yet. Im guessing your building something similar to the HO trials tracks you see on youtube.

[Pikey]

Yes, 1:76 standard Oxford model with standard tyres. I used the Network Rail liveried model to convert to start with, but I've just bought one in military camo to use specifically on the diorama.

 

Its going to be similar, although the ones I've seen tend to look a bit fantasy/artificial, I'm going to try and create a bit of proper English muddy hillside like you'd get to drive around on an off-road driving experience day.

 

Here's a video of me testing it:

 

 

And here's a picture:

 

Edited June 14, 2018 by Pikey

[NRS91]

Loving that little Landy! Is there a build thread for it?

[Regularity]

It’s gripped. It’s sorted.

Let’s off-road.

[CME and Bottlewasher]

Wonderful stuff!

 

Looking forward to seeing the Landi tackle 'the mother of all gullies' lol!

Edited June 14, 2018 by CME and Bottlewasher

[otherplanet]

I am loving that landrover, it drives really nicely and looks so good climbing those slopes. I look forward to seeing the fully detailled scenics.

I was tempted to do a series 1 for Upper B before the invites dried up.

However this sets the bar very high. I think I need to go back and reassess my test Road.

[otherplanet]

Concerns have abated following trials of alternate vehicles. The Atkinson can only cope with this incline before sliding back down the hill. (even when just placed statically on the sloping surface).

However. The K8 will cope with this incline.

Any steeper and it starts to topple backwards on its rear wheels. But still doesnt slide.

It cant quite climb this angle, having insufficient torque because it is too highly geared. But at only a few degrees lower it will happily run up the test track.

Overall I am happy. Even the Atkinson can climb more than I need. but some further experimenting with rubber tires and or plastidip is definitely worth the effort.

Meanwhile the road surface is not the limiting factor even in its slightly smooth and glossy state.

Additionally, my efforts with the static grass (which I have never used before so excuse the imperfections) seems to leave the surface navigable even when placed between the ruts.

Its not up to the standard of Pikey's hill climb trials track, or landrover, but comfortably meets my needs.

[Pikey]

That looks great that does. Definitely the effect I'll be going for when I get round to adding some greenery to my hillside  

[otherplanet]

Happy New Year to everyone.

Its been a while and work on the layout has all gone a bit ‘armchair’ due to other commitments. So i decided to re-energise with a spot of vehicle building. I completed the mods to the servo CAD design and modelled up the transaxle for the Dennis subsidy truck. I also modelled replacement wheels with the tyres missing and designed some new acetylene headlamps as the military spec model only has one headlamp. All added to a sprue, the resulting collection of parts duely arrived from shapeways at the beginning of December.

 

 

Careful use of the dremell allowed me to hollow out the bonnet casting plus the crank case and gearbox sections of the chassis to take a 6mm gear motor. It’s quite steeply angled and not quite as perfect a fit as I had hoped, so its going to protrude into the cab slightly more than the original bulge in the floor. hopefully it won't stand out too much.

 

 

The transaxle went together nicely, it uses a 2mm dia worm and a 22tooth pinion to deliver drive to the wheels. My usual brass tube bearings are set into the SLA holes.

 

 

The grey shape in the top right is the original resin casting.

I’ve used brass tube and wire to build a pair of 2mm diameter universal joints on a drive shaft. this is glued to the motor at one end, and the input to the transaxle at the other. Since there is no rear suspension to compensate for, the small amount of freeplay in the UJ’s is sufficient to allow free running without requiring a spline connection.

 

 

I managed to achieve my objective of getting the wheels turning before the end of 2018 (on the 29th), they run very smoothly and satisfactorily at a reasonable slow speed. If needed I can change the worm to a 2.8mm diameter with the appropriate reduction in pinion to make it faster.

 

2019 will aim to get the servo built and working; since I have “improved” the design I hope it works OK. I also need to try out the plan to make tyres from square rubber drive belts to go on the wheel rims. But most importantly, I need to get the new camera working; which is suitably tiny but at the moment I cannot get an image out of it.

[Giles]

Your usual extraordinary stuff!!!!!

 

Your workmanship tend to be so much better than my bodging - I do like it!

 

I've just completed a Mechanical Horse in 7mm ( old type, not the Scrab), and that uses the 6mm x 8mm gearmotor which I find excellent in performance.

[otherplanet]

Thanks Giles, your recognition is most valued.

I have been watching the progress of your mechanical horse, it looks really nice in the green. I am occasionally tempted to do a second Scarab, now I have learnt so much. But since Upper Benllech is now formally retired, it would be a bit redundant at the moment.

[Pikey]

Cool

 

Brass UJs and my own 3D printed gearbox casing and steering axle parts is something I need to get on with, as it opens up a whole world of possibilities  

 

How did you make a UJ? Could you get a closer picture of it please? I really want to try and motorise Oxford's JCB Telehandler - but it has 4 wheel steering so I will need something like that to do it.

[otherplanet]

I have some pictures from the build. I will get them off the camera and share them.

[Pikey]

I did find these on shapeways, which I might order just to see what its like

 

https://www.shapeways.com/product/ZAUC5L5S3/kardangelenk?optionId=58142919

Edited January 4, 2019 by Pikey

[otherplanet]

Intriguing, They look very promising, I will be very interested to see how they go.

I haven't thought to search in German on shapeways. Although I have used it to look for components on other sites in the past.

 

 

 

The UJ is built from 2 tubes of 1.8mm OD 0.2mm wall thickness tube.

I cross drill the ends with a 0.45mm drill and then use a very fine piercing saw to cut the gaps out either side, and then a narrow file to finish the profile.

I then flatten the arms of the yoke by squeezing them in a pair of pliers. 

 

The spider is made from 1.2mm tube of slightly thicker wall section.

I use a 0.5mm piercing saw to cut a pair of slots into the end about 0.5mm deep.

This becomes a seat for two pieces of 0.45mm dia wire.

 

 

I cut two pieces of wire to a convenient length and then place them in a small vice at 90 degrees and squeeze the vice to create a matching set of dents so that the two wires sit in the same plane.

 

 

These are then soldered into place on the spider and trimmed to length, the completed spider can then be cut off the end of the tube.

Once the spider is finished it is fitted into each of the yokes by bending the arms out slightly until the tips of the wire can be slotted in. Then reform the arms back parallel.

 

 

This all sounds quite complicated, but its relatively quick once you have built a few.