My 1st project: TIE Crawler from the Star Wars Expanded Universe

My 1st project will be another: the TIE Crawler (photo below) from the Star Wars Expanded Universe.
It’ll move forward, backward, left and right. That’s all.

What do you think about it? :slight_smile: :smiley:

TIE_Crawler.jpg

Simple design with Skid steering, the code should be very simple too. From your picture, there doesn't seem to be a lot of room, where do you plan to put everything? The motor controller you may be able to salvage or just make your own, and you might want to use either an Arduino Nano, micro, or Mini.

HazardsMind: Simple design with Skid steering, the code should be very simple too. From your picture, there doesn't seem to be a lot of room, where do you plan to put everything? The motor controller you may be able to salvage or just make your own, and you might want to use either an Arduino Nano, micro, or Mini.

Can you be more clear please? :|

Your toy has skid steering ( like a tank) but judging from the picture, it looks like space is very limited. Can you specify the dimentions? Your code depending how you go about controlling it, will need a motor controller to drive the motors. The usual ones might be too big, so you may need to make your own. There are also plenty of skid steering codes on this forum, I have some myself.

But first see how you want to control it IR, bluetooth, RF or even Xbee. Then see how much space you have to work with.

I just recently built this basic kit that I found on Amazon. It has a very similar functionality to what you are looking for and is a good starting point.

http://www.amazon.com/Tamiya-Track-Wheel-Set-TAM70100/dp/B00061HHRC/ref=pd_sim_t_4

In addition to that kit, you'd need a double gearbox for independent tread control. http://www.amazon.com/Tamiya-Double-Gearbox-Independ-4-Speed/dp/B001Q13BIU/ref=pd_bxgy_t_img_y

While it doesn't fit exactly with your original picture, you can combine all the components on their universal mounting plate really easily. http://www.amazon.com/Tamiya-Universal-Plate-TAM70098/dp/B00061HHR2/ref=pd_bxgy_t_img_z

Here is a picture of my project using these components: https://www.dropbox.com/s/r8gl4rc8fayvwwh/2014-01-15%2011.56.55.jpg

I used an Arduino UNO and a cheapo L298n breakout board with some on-board passives for protection. I think it cost me 5-6 dollars.

Annnd, my last note, the motors that come with the double gearbox kit are rather crude. They do work, and are controllable with the Arduino, but I upgraded to better 6v ones and I would suggest you do the same.

HazardsMind:
Your toy has skid steering ( like a tank) but judging from the picture, it looks like space is very limited. Can you specify the dimentions? Your code depending how you go about controlling it, will need a motor controller to drive the motors. The usual ones might be too big, so you may need to make your own. There are also plenty of skid steering codes on this forum, I have some myself.

But first see how you want to control it IR, bluetooth, RF or even Xbee. Then see how much space you have to work with.

Well, actually my idea is to make it big. I think something like 40 cm*30cm (or smaller or bigger), because despite it’ll be a simple model, I want to make it IMPRESSIVE.
So I think that the normal components could be good enough for it. The codes will be very useful, but I’ll need them later.
And I want to control it with a controller made always with Arduino. I was thinking to a very simple controller with two Pads (one for forward and backward movements and one for left and right movements), an On/Off button to turn the controller on/off and a button for the light turbolaser (retractable turret) that you can see in the technical scheme.

However the TIE Crawler in the black picture is not a toy. It’s just a 3D model made with computer.

Seeing as how it is skid steering, you can use a single joystick to control it, or you can use a standard up, down, left, right buttons. Do you want to control the speed too?

HazardsMind: Seeing as how it is skid steering, you can use a single joystick to control it, or you can use a standard up, down, left, right buttons. Do you want to control the speed too?

Actually, I saw many RC tanks controlled by joysticks with 2 pads. So the joystick that I would want to build has just:

  • Pad 1 for forward and backward movements
  • Pad 2 for left and right movements
  • On/Off button to turn on/off the controller
  • Battery compartment
  • Button for a retractable component

Controlling the speed isn't a bad idea. But I don't think I need it. The TIE Crawler is a tank, so I would want that it would move at the same speed of a normal tank.

Moreover, the user "cwhummel" suggested to add a speaker with an mp3/wav module to make that awesome noise they make in the real life (and in the movies, as he said). And I agree. It would make it more realistic.

Ok, your idea is definitely possible. For your controller, do you want to recycle a gaming controller like a PS2/3 or Xbox, or do you want to make it from scratch? Either way, it will be easy but, if you decide go with a PS3 or Xbox controller, then you will need a USB host shield and a Bluetooth dongle.

If you make it from scratch then you can use either an Arduino Nano, Micro, or Mini, and your two pads and buttons.

user "cwhummel" suggested to add a speaker with an mp3/wav

Ok, cool. Here is a small WAV/AD4 module. LINK HERE

HazardsMind: Ok, your idea is definitely possible. For your controller, do you want to recycle a gaming controller like a PS2/3 or Xbox, or do you want to make it from scratch? Either way, it will be easy but, if you decide go with a PS3 or Xbox controller, then you will need a USB host shield and a Bluetooth dongle.

If you make it from scratch then you can use either an Arduino Nano, Micro, or Mini, and your two pads and buttons.

user "cwhummel" suggested to add a speaker with an mp3/wav

Ok, cool. Here is a small WAV/AD4 module. LINK HERE

Well, my TIE Crawler is very simple. So I want to make the controller from scratch. Thank you for the link you gave me. :)

If you want to make it from scratch, and use joysticks, go with these guys. The board was designed really well. I bought the ones from Sparkfun and I can only use 3 of the mounting holes. http://www.adafruit.com/products/512/

Alex_Co: Well, actually my idea is to make it big. I think something like 40 cm*30cm (or smaller or bigger), because despite it'll be a simple model, I want to make it IMPRESSIVE.

The larger the chassis is, the larger the gear motors will need to be to move it; same for the batteries, and motor controllers, etc. This all leads to a larger cost. Furthermore, if you don't understand the torque requirements for the gear motors and such, you can find yourself in a weird feedback loop (as you add weight/mass, you need more torque - which means larger motors, and larger batteries, which adds more weight/mass - and so forth).

So what you need to do is have a good idea (beyond size) how much everything is going to weigh, and what kind of torque you are going to need to move it (and what kind of terrain it will be moving on - flat ground, inclines and slope angles, soft dirt or hard tile, carpet, etc). Once you know that, then you can size everything out properly so you can purchase the proper gear motors.

Alex_Co: So I think that the normal components could be good enough for it. The codes will be very useful, but I'll need them later.

Well - and Arduino and such, certainly - but likely you are going to need something more than just the simple (and lower cost) robotics components that are out there. To move something of the size you are envisioning is going to require more than a bit of power. If you don't need speed control, then you could use relay controller modules to turn on/off (and change direction) of the motors, but you'll still need to find the proper motors (and make sure they stay in the current range of the relay boards - or build your own relay controller).

Alex_Co: However the TIE Crawler in the black picture is not a toy. It's just a 3D model made with computer.

Since this isn't something "off-the-shelf" - what do you intend to build it with? I'd personally use laser-cut pieces of plywood or acrylic; you could also go with thin aluminium if you're comfortable working with the material. Steel would likely be too heavy; you could potentially go for a combination of all the materials if you wanted.

My advice would be to try to find common items or such that can be modified to make the hull/chassis rather than try to fabricate everything from scratch (you still need to do that anyhow to a certain extent) - the difficult part would likely be the spherical center pod (perhaps a couple of bowls or a hamster ball could work - you can also purchase acrylic spheres if you look around - and some metal outlets sell steel hemispheres for decorative work).

The difficult part to fabricate is going to be the whole track system - you can't easily purchase small tracks off-the-shelf (well; that's not completely true: Tamiya makes scale metal tank tracks and such for modeling - whole tanks even - then there's the whole tank military simulation stuff - but those parts and such are very expensive).

Most people who try to build their own tank-like vehicles typically have to tackle and build their own tread system; there are those out there who home-build tanks for paintball competition - you can get ideas on how to do so:

http://www.rctankcombat.com/articles/track-systems/

Your machine might be too small, though, for such a built-up system. Another option you see in such cases is to use a timing cog belt turned "inside-out" (or one that is double-sided); the cogged side of the belt form your treads, and the inside of the belt is driven.

This won't be an easy or quick project, but if you break it down into smaller steps, you can get it done without it overwhelming yourself.

cwhummel: If you want to make it from scratch, and use joysticks, go with these guys. The board was designed really well. I bought the ones from Sparkfun and I can only use 3 of the mounting holes. http://www.adafruit.com/products/512/

Thank you cwhummel, I'll keep the link. :)

Well, I don't want to make it too big. It has to be something of impressive, but not so excessive.

The larger the chassis is, the larger the gear motors will need to be to move it; same for the batteries, and motor controllers, etc. This all leads to a larger cost. Furthermore, if you don't understand the torque requirements for the gear motors and such, you can find yourself in a weird feedback loop (as you add weight/mass, you need more torque - which means larger motors, and larger batteries, which adds more weight/mass - and so forth).

So what you need to do is have a good idea (beyond size) how much everything is going to weigh, and what kind of torque you are going to need to move it (and what kind of terrain it will be moving on - flat ground, inclines and slope angles, soft dirt or hard tile, carpet, etc). Once you know that, then you can size everything out properly so you can purchase the proper gear motors.

I want to make it big, but within a limited cost. There is one thing I don't understand: what do you mean with "the torque requirements for the gear motors"?

About the terrain, well it will be like a normal RC tank: for different terrains. I saw that many RC tank can go on different types of terrains (flat ground, inclines and slope angles, soft dirt or hard tile, carpet, etc.).

To move something of the size you are envisioning is going to require more than a bit of power. If you don't need speed control, then you could use relay controller modules to turn on/off (and change direction) of the motors, but you'll still need to find the proper motors (and make sure they stay in the current range of the relay boards - or build your own relay controller).

Could you be more clear, please? :)

Since this isn't something "off-the-shelf" - what do you intend to build it with? I'd personally use laser-cut pieces of plywood or acrylic; you could also go with thin aluminium if you're comfortable working with the material. Steel would likely be too heavy; you could potentially go for a combination of all the materials if you wanted.

For the weight I can't establish that without knowing which material. But, about the material, I was thinking about plywood, plastic and aluminium too. But acrylic is a transparent material, so I don't think is very good for this project. Yeah, steel is too heavy, so I've already excluded it from the list.

My advice would be to try to find common items or such that can be modified to make the hull/chassis rather than try to fabricate everything from scratch (you still need to do that anyhow to a certain extent) - the difficult part would likely be the spherical center pod (perhaps a couple of bowls or a hamster ball could work - you can also purchase acrylic spheres if you look around - and some metal outlets sell steel hemispheres for decorative work).

For the spherical center pod I'm taking into consideration different ways, but every way will depend from the size of the model. The bigger is the model, the bigger will be the spherical center pod.

The difficult part to fabricate is going to be the whole track system - you can't easily purchase small tracks off-the-shelf (well; that's not completely true: Tamiya makes scale metal tank tracks and such for modeling - whole tanks even - then there's the whole tank military simulation stuff - but those parts and such are very expensive).

Most people who try to build their own tank-like vehicles typically have to tackle and build their own tread system; there are those out there who home-build tanks for paintball competition - you can get ideas on how to do so:

http://www.rctankcombat.com/articles/track-systems/

Yeah, I agree with you. The track system of the TIE Crawler is very different from a normal tank's track system. So I'll make it from scratch like, as you said, many people that home-build tanks.

Thank you for the link. I'll keep it for when I start. :)

And this is a page where you can see a detailed 3D model of the TIE Crawler: http://www.turbosquid.com/3d-models/tie-crawler-3d-model/706295

As I said before, space is going to be a limiting factor. You may want to get either steppers, DC pancake motors or use a regular DC motor with a worm gear to drive the treads. Your best bet for size comparing would be to make a very simple frame with cheap materials, to get an idea of how it will look and where everything will fit.

HazardsMind: As I said before, space is going to be a limiting factor. You may want to get either steppers, DC pancake motors or use a regular DC motor with a worm gear to drive the treads. Your best bet for size comparing would be to make a very simple frame with cheap materials, to get an idea of how it will look and where everything will fit.

Yeah, a simple frame it's a good idea. Actually I'm thinking to do my model with aluminium, but if it won't be possible, I'll do it with plastic or another material.

I don't know about the motor. The best idea would be to do like other people do when they build their RC tanks.

Alex_Co: I want to make it big, but within a limited cost. There is one thing I don't understand: what do you mean with "the torque requirements for the gear motors"?

Well, gear motors have a torque rating - generally measured in lb-ft, oz-in, kg-cm, or N-m (among others); that measurement will tell you how much weight/mass the motor can move.

Alex_Co: About the terrain, well it will be like a normal RC tank: for different terrains. I saw that many RC tank can go on different types of terrains (flat ground, inclines and slope angles, soft dirt or hard tile, carpet, etc.).

Yes - and most have probably had the calculations done to know what kind of motors and gear ratios they need to produce the proper torque (on average) for the terrain they will be operated in. You will need to do these same calculations to know how much torque you need for a given terrain. You can either do the calculations and take an average (like do a flat-ground calc, and a 45 degree slope calc, then take an average) - or just do a single "worst-case scenario" (45 degree would probably be realistic) and use that as your "maximum". Or do a flat-ground calc, add 50 percent and wing it. Or don't do any calc at all, get the biggest damn motor you can afford, and pray it will work.

Alex_Co: Could you be more clear, please? :)

Well - if you have motors that have a stall current rating of say, 20 Amps, then you'll want your relays to have a contact current rating at least of that amount if not a bit more (and also be rated for inductive loads - relays are rated based on whether they will be handling resistive, inductive, capacitive, or signal loads - check the datasheet if possible).

Alex_Co: But acrylic is a transparent material, so I don't think is very good for this project.

Not all acrylic is transparent - you can get it opaque, shiny, mirrored, matte - plus it can always be painted. Don't discount it as an option; it's one drawback is that it can be difficult to work with (but that goes away almost entirely if you have access to a laser cutter - heh).

Alex_Co: Yeah, steel is too heavy, so I've already excluded it from the list.

Thin sheet steel might not be too bad - plus it is fairly easy to work with - you can cut it fairly easily, form it with simple tools, and easily weld, braze, or solder it. Aluminium can be cut ok and formed somewhat easily, but you can't easily weld it or solder it (there does exist a product out there called "AlumiWeld" that's basically a low-temp brazing alloy - http://www.alumiweld.com/ - I'm not sure how well it works, though).

Alex_Co: And this is a page where you can see a detailed 3D model of the TIE Crawler

The only problem with that model is that it is a 3D computer graphics model, and likely not suited at all for use in fabricating a real-world machine. It should be looked upon as a reference only - not as a plan. To build your machine, you should come up with your own plan on how to build the machine; such a representation could be done using pencil and paper and some 2D drawing, or a full 3D drawing in Autocad if you have the skillset for it.

An area of concern on the particular machine is going to be the torque of the central pop and axle "structures" on the tread housings; depending on how much weight is being borne on the perpendicular axis of the structure will determine what kind of fastening or other structural attachment to the tread housing is needed (otherwise, the thing will quickly fall apart over time).

cr0sh:

Alex_Co: I want to make it big, but within a limited cost. There is one thing I don't understand: what do you mean with "the torque requirements for the gear motors"?

Well, gear motors have a torque rating - generally measured in lb-ft, oz-in, kg-cm, or N-m (among others); that measurement will tell you how much weight/mass the motor can move.

Alex_Co: About the terrain, well it will be like a normal RC tank: for different terrains. I saw that many RC tank can go on different types of terrains (flat ground, inclines and slope angles, soft dirt or hard tile, carpet, etc.).

Yes - and most have probably had the calculations done to know what kind of motors and gear ratios they need to produce the proper torque (on average) for the terrain they will be operated in. You will need to do these same calculations to know how much torque you need for a given terrain. You can either do the calculations and take an average (like do a flat-ground calc, and a 45 degree slope calc, then take an average) - or just do a single "worst-case scenario" (45 degree would probably be realistic) and use that as your "maximum". Or do a flat-ground calc, add 50 percent and wing it. Or don't do any calc at all, get the biggest damn motor you can afford, and pray it will work.

Alex_Co: Could you be more clear, please? :)

Well - if you have motors that have a stall current rating of say, 20 Amps, then you'll want your relays to have a contact current rating at least of that amount if not a bit more (and also be rated for inductive loads - relays are rated based on whether they will be handling resistive, inductive, capacitive, or signal loads - check the datasheet if possible).

Alex_Co: But acrylic is a transparent material, so I don't think is very good for this project.

Not all acrylic is transparent - you can get it opaque, shiny, mirrored, matte - plus it can always be painted. Don't discount it as an option; it's one drawback is that it can be difficult to work with (but that goes away almost entirely if you have access to a laser cutter - heh).

Alex_Co: Yeah, steel is too heavy, so I've already excluded it from the list.

Thin sheet steel might not be too bad - plus it is fairly easy to work with - you can cut it fairly easily, form it with simple tools, and easily weld, braze, or solder it. Aluminium can be cut ok and formed somewhat easily, but you can't easily weld it or solder it (there does exist a product out there called "AlumiWeld" that's basically a low-temp brazing alloy - http://www.alumiweld.com/ - I'm not sure how well it works, though).

Alex_Co: And this is a page where you can see a detailed 3D model of the TIE Crawler

The only problem with that model is that it is a 3D computer graphics model, and likely not suited at all for use in fabricating a real-world machine. It should be looked upon as a reference only - not as a plan. To build your machine, you should come up with your own plan on how to build the machine; such a representation could be done using pencil and paper and some 2D drawing, or a full 3D drawing in Autocad if you have the skillset for it.

An area of concern on the particular machine is going to be the torque of the central pop and axle "structures" on the tread housings; depending on how much weight is being borne on the perpendicular axis of the structure will determine what kind of fastening or other structural attachment to the tread housing is needed (otherwise, the thing will quickly fall apart over time).


The only problem with that model is that it is a 3D computer graphics model, and likely not suited at all for use in fabricating a real-world machine. It should be looked upon as a reference only - not as a plan. To build your machine, you should come up with your own plan on how to build the machine; such a representation could be done using pencil and paper and some 2D drawing, or a full 3D drawing in Autocad if you have the skillset for it.

An area of concern on the particular machine is going to be the torque of the central pop and axle "structures" on the tread housings; depending on how much weight is being borne on the perpendicular axis of the structure will determine what kind of fastening or other structural attachment to the tread housing is needed (otherwise, the thing will quickly fall apart over time).

Well, that 3D model is a picture that I found on the web. I didn't made it for the project. :) But I'll take everything you said in consideration, thank you. It'll be a long work, I think.

Yes - and most have probably had the calculations done to know what kind of motors and gear ratios they need to produce the proper torque (on average) for the terrain they will be operated in. You will need to do these same calculations to know how much torque you need for a given terrain. You can either do the calculations and take an average (like do a flat-ground calc, and a 45 degree slope calc, then take an average) - or just do a single "worst-case scenario" (45 degree would probably be realistic) and use that as your "maximum". Or do a flat-ground calc, add 50 percent and wing it. Or don't do any calc at all, get the biggest damn motor you can afford, and pray it will work.

But how do I calculate them? I don't really know it! :(

Well, gear motors have a torque rating - generally measured in lb-ft, oz-in, kg-cm, or N-m (among others); that measurement will tell you how much weight/mass the motor can move.

And how can I measure this? :O

However, at the beginning my idea was to build also the cockpit (with a small AT-AT Pilot that I bought in a Toy Shop inside). But now I think that maybe is much better to use the cockpit for the engine and the Arduino electronic components.

So in this case I think that I should have enough space for the electronic and mechanical part. What do you think about it?

One more thing: I'm thinking to use aluminum as material. How much would my model weigh?

An aluminum body will be very light about 1 or 2 lbs, if that, but the real weight will come from the motors and battery.