Terminator T-1 reborn and redesigned.

 Our T-1 or T1FNY as she is called has been out and about at a few shows over the last few weeks. 

There have been a few updates to the object recognition system with the introduction of adding a few new objects, teaching T1FNY what to do when she see's these objects, to the object library. We have also been out doing a photoshoot with T1FNY. We still have a few problems with getting the logic switches programmed on the FrSky radio system to allow the gun sound too sync with the gun spin when in comic con demo mode.

An update on the gun systems, Initially I wanted to build a gun system that would simulate firing using the propane system we have used before but the problem has always been the weight of the guns.

A method has now been sorted to get the guns to fire but using Airsoft rounds instead. Fitted with tracer rounds when filmed in low light look awesome and sound great as well. Obviously these can only be used in controlled environments and, sorry, will not be demonstrated at public shows.

The T-1FNY on guard at a secret military location in Wiltshire.

T-1FNY has had a few more tattoos, serious Bad Ass.

Terminator T-1

 It has been a long journey from the initial cardboard template to the final T-1-FNY

Like all builds they go through distinct phases and she is now in the final stages, the fine touches.

This is where the elements of personality and realism are added. All those small details that were not really important in the construction phase have now been added.

All the wiring in the upper section has now been tidied up and extra cooling added to the Raspberry Pi 4 computer

The old metal connectors to the upper section have now been replaced with waterproof plastic ones. They are still screw lock but much stronger.

Some of the metal done nuts have been replaced with fibre to try and reduce the weight

Much larger LiFePO4 Battery.

Calibrated the Amp and low section volt meter.

Tread pattern added to tracks.

An extra 5v output.

External limit switches fitted to the top lift

Read section added to head

Gun covers added, apparently required when we go to shows as people might think the guns were real???

Face mouldings added

Starting to build all her accessories ready for the Show in May 

So what is still left to add. We have been working very hard on developing the show which T-1-FNY stars in which will have its first showing at the NEC on the 13/14 May 2023.

In terms of technology that is still to be added I will be doing a bit more work with the object recognition and seeing if I can get anymore out of the Raspberry Pi 4. The problems I am encountering are that these small computers like the raspberry Pi and Jetson Nano are simply not powerful enough to run accurate object recognition. If I want to control the robot via these systems I need much more computing power so it looks like she might have to be tethered when in this mode, connecting her to a more powerful computer. I will see, still loads to do with this. 

What I would really like to do is make the guns a bit more realistic. The main problem I have with them is that they need to be lightweight. Even adding Airsoft mechanisms to the main system adds too much weight. The only way I would be able to add a firing effect to them is find a way to do it without adding so much weight that it will cause the upper and lower lift motors to much stress. Time to put my thinking hat on.

Terminator T-1

Not all Terminator T-1's look the same. Clearly Cyberdyne Systems would not have produced identical T-1 models. The basic frames would have been the same but there would have been subtle differences.  The two models T-1-7 and T-1-8 we see in the action sequence of the film but we also see a room full of covered T-1's. 

Robot Centrals T-1 is one of those variations. 

Variations in design would have included;

Modified head with extra sensors and kevlar armour

Modified track system providing more power and traction

Slimline bodywork removing weight and allowing better access for repair.

Nuclear power source.

All fun aside, our T-1 or T-1-FNY as she is called is was built twenty years after the film prop were completed.

Technology has developed a great deal in that time and one of the things we wanted to include in our T-1 build was autonomous features. I previously wrote about the Pololu Meastro boards and use of Raspberry Pi 4 for the object recognition systems the T-1 uses.

One other feature I wanted to give T-1-FNY was the ability to know where she is and be able to move into a sentry mode on her own. To this end I used this, the ArduPilot autopilot board. I bought this board years ago to build into a drone but it never happened and it just sat in a draw not being used until now. Re-programmed with new firmware and able to run a ground vehicle it will be ideal to use on the T-1.

It is very simple to use, if effect sits between the Pololu board and multiplexer and will be switched from the FrSky radio. The only downside is that it needs to see the sky, acquiring satellites, to work so using it in an exhibition center wont work. Outside though it is great. I can program in simple tracks with way points that the T-1 can follow creating a small sentry path around out workshops. Combining this with the object recognition and ability to spin the guns up this build is providing lots of fun. 

ArduCopter ArduPilot autopilot board .

                                                               Working on Electronics

 

Lots more work has been completed on T-1-FNY's electronics tidying up all the wiring and making sure that nothing snags or moves as she trundles around.

One new feature that has been added are limit switches. I was struggling to find limit switches that where strong enough for what I needed but then came across these.

They are now fitted to the upper and lower lifts and the body rota. 

They are not strictly speaking necessary on the lifts as the actuators have built in limit switches but they have been added anyway adding an element of adjustability.

Where they were really needed was the body rota. Because I am using a tether and not a slip ring I don't want the body to spin 360 which would look silly anyway. The limit switches and motor stops now make the control system idiot proof plus allow autonomous control to be applied to the rota.

Terminator Hunter killer Battle Tank

The video above shows T-1-FNY reacting to cars driving past and being told they are not a threat.

 I never used to be into writing code and building my own control systems, I have always been a more traditional builder, however, the T-1 project has seriously opened my eyes not just to how much fun developing control system is but how easy it is to learn. 

Most of my builds are RC using a convensional RC Transmitter and Reciever. 

In building T-1-FNY and moving into this second phase of the build it has been fun giving the robot a sense of autonomy. It has also been a bit scary, as it is very easy to just flow with the technology and not stand back and think about failsafes and consiquenses. What I mean by this is that making T-1-FNY drive forward on her own, after recognizing a colour and moving towards it, is simply a few lines of code and a go button. Problem with this is that 50 percent of the time it will work great but sometimes it does not and it is in these moments that you stop and think how difficult this technology really is in making it fulproof. What I have descovered is that computing power is everything and a small Raspberry Pi, even though it is great, is simply not powerful enough to get to 100 percent. Even the bigger Nvidia Jetson or even larger computers still are not fulproof. To be able to confidently give T-1-FNY autonomous control over her power systems using object recognition as the control triggers I she must be at atleast 99 percent sure that the object she is seeing is that object. I can not allow a 300kg robot autonomous control on the basis that the object she recognized at 46 percent is the target object. 

Anyway what I mean by all this is that using these control systems, object recognition and external gyro control systems is so much fun but it has given me a new found respect for autonomous robot system and how much computing power and great coding they must have to be so smart, also how far we re from a 'real' T-1. 

I have now come to the conclusion that the follow system I was developing for T-1-FNY is now shelved and I an going to concentrate on using the object recognition and external gyro control system to control other parts of the robot, head, arms, rota,lifts, etc and keep drive control fixed to RC. There are still tons of failsafes I need to build in, even in moving her upper body and shoulders as this assembly still weighs in at 80kg. 

Hopefully by the time we launch the T-1 build at the NEC in May I will have lots of these systems up and running and be able to demo them, or atleast T-1-FNY will.

T-1 autonomous mode

 T-1-FNY Autonomous Mode

Definition of Autonomous = Independent and having the power to make your own decisions. 

It always makes me laugh when people advertise props at Comic Cons saying they are Autonomous not really having a clue what the word actually means.

It was always the plan to give T-1-FNY a few autonomous features

So how does this relate to our T-1?

Given her size and weight unfortunatley there are features that we can simply not make autonomous (the PLI  wont allow it.)

Having a 300kg robot run out of control and using the excuse she was doing it because she wanted to would not cut much weight in a court of law.

The autonomous features on the T-1-FNY will be limted to her head. body, guns and shoulder movements. As well as operating in autonomous mode she will need a RC full override which can be switched in at any given moment

This switching duty will be handled by the small but very capable Pololu 4Ch RC Multiplexer. 

With this tiny board we will be able to input both control signals from a Pololu Maestro

and FrSky TDR18 reciever and using a switch on the RC transmitter switch between the two.

The Pololu Masestro board will run a series of programs which will be triggered in turn by triggers sent from the Raspberry Pi 4 using the Object recognition software. 

In effect what this means is that certain objects or colours detected will trigger a program which will inturn control the head servos. Depending on the percentage probability that the robot has detected the object will determin which script on the Pololu runs. It sounds complex but in reality is very simple.

The T-1 will appear to react differently to varying inputs from the camera.

In effects she will chose which program to run depening in the probability that she is seeing the target object.

As I deverlop this autonomous mode I will add more scripts which will also control the shoulder, guns and lifts.

Terminator T-1-FNY Control system

                                                            FrSky Tandem XE Transmitter

Terminator T-1-FNY Battle Tank

Comes complete with a nice case and shoulder strap.

Four pop out rotary switches, two on each side.

Two blanks on each side for adding extra switches

or sockets for external wired control. 

Very nice well balanced 3 axis gimbals.

Pop out struts for shoulder strap.

Nice shape in hand

Usual external module slot and battery compartment.

Top mounted sockets. USB C for charging

FrSky Tandem X20s.        FrSky Tandem XE

Internals of radio

Pop out struts for strap.

Mecahnism looks fairly strong and internal brackets are reinforced

Main board

Location of molex connector for extra switches

Bluetooth

Side slider NOT sprung

Remove bolt pointed at to add spring to Throttle

Pop out switch unit.

Secured with two screw on back of radio

No need to take back of radio of to access

Adding Swiches to extra ports

You can add upto four switches directly via the JST SH 1mm 3pol connectors on the removable switch blocks. You can also add a further two switches soldered directly to the main board. You can see here I have added four mini momentary toggle switches. Simple to wire up, Black wire to center of pin of switch and red to one pin and yellow to the other. Plug it in and the radio will detect the switches, simple. Go to the hardware setup page and you can set the switch to whatever it was you added,i.e. 3pos/2pos or momentary switch. I will also be adding 2.5mm jacks to the switch ports to allow remote wired switches. 

After moving from the Spektrum DX18 to the FrSky X20s, controlling the larger robot builds has been so much easier. There was nothing wrong with the Spektrum DX18, it was a great radio, just very analog. What I mean by this is that for controlling simple builds it was fine but there were no programming options, something I have found I now need on the larger robot builds. 

So if the FrSky X20s was so good why bother to spend more money on the FrSky Tandem XE?

When controlling the larger robots or working on set it is much easier to use a tray radio plus I like the look of the new FrSky XE, modern/retro.

Both use the Ethos OS so in this sense are identical. What the XE offers over the X20s is more direct inputs. Now for a field flyer I cant see how extra inputs would make any difference at all so the X20s would be fine.

Where the XE scores over the X20 is that it is fitted with dual 3 axis Gimbals with switches. I have used 3 axis gimbals on radios the size of the X20s before and they always feel too big and difficult to use. Having a bigger form factor the XE deals with the 3 axis gimbals well and they don't feel overly large.

What the 3 axis gimbals offer the robot controller is much more fredom over movement.

For example: on the Terminator T-1 I can use one hand to control the power, track slip and rear track turn. What this means is that it is all more intuative. Push forward on the stick then rotate the stick to turn the rear track then input a small amount of slip. Combine this with logic switchs to feed the power correctly to each track the whole robot moves much more freely than it would with two hand input.

This then frees up the left gimbal to control the body movement, rotoation and upper and lower body lifts, which can now all hapen at the same time.

In the old days I would have used a radio equiped with a wired trainer link and wired remote switches controlled by three people. On a set this can sometimes be much easier but this radio opens up a whole new range of posibilities for the single operator. 

All of this extra intuative control creates a far better experience for an audience. 

I will still be keeping the X20s for controlling the smaller robots and to use in situations where I need to disapear into a crowd but still need to control the robots, you cant do this with a tray radio. 

The FrSky Tandem XE is well built however being larger than the X20s does not feel as solid.The X20s is built like a brick however, very, very solid radio. 

The XE uses high quailty plastic and metal to offer a very nice feel in hand but by it nature has more room inside it for additions. This makes it feel lighter than the X20s even though it is heavier. It is very hard to explain how both feel in hand. You feel that the X20s could be dropped and used in really harsh conditions and easily survive where as the XE requires a bit more respect. 

Switches on the XE are very good and the gimabls excellent.

Both screens are very clear and can be configured to show whatever info you want.

Updating firmware via Ethos suite is the same as the X20s and very simple.

Ethos OS

The Ethos OS is excellent and simply ideal for any robot builder given the nature of the logic and special function switches. In essence you can create very complex control systems minimal user input. 

It is easy to use plus offers a user interface to allow the radios to updated easily.

Hopefull as the OS is developed I have no doubt need exciting features will be added.

Opening up the XE you can add a further four switches or sockets( so remote switches can be used). There is space available for four switches and molex connectors ( JST SH 1mm 3pol) ,onto the main board inside so no soldering is needed, simply plug in. Switching from mode 1 to 2 is easy and adding a spring return the the throttle is as simple as removing and internal screw. ( you can also do this on the X20s).

External switches are very tough plus there are four rotary controls that pop out when needed. The side sliders are not sprung as some people have suggested, they are the same as the X20s.

Para links works great just like the X20s. Linking external gyro control boards via bluetooth using the para trainer function also works very well. I use the Arduino Nano33 BLE sense, great controller to use with the XE or X20s. 

Things I am not to sure about are the pop out strap posts at the base of the XE. The shoulder strap is fine but I find the posts a bit flimsy. They are metal and seem strong, only time will tell if they stand up to the rigours of using them each day. 

Internal battery on the XE is excellent and lasts much longer than the X20s.

Bluetooth audio is missing on the XE but it is next to useless anyway on the X20s so no loss really.

The problem with the bluetooth audio is the delay if using it to trigger external sounds on models. 

Reciever used with Terminator T-1-FNY

Been asked asked a great deal what receiver do we use in the T-1-FNY.

We use these, the FrSky TDR 18

Very solid reciever offering 18ch out of the box(so to speak) without adding any extra modules for more channels. On board telemetry as well as voltage and current sensors built in which is handy. 

To Conclude

Is the FrSky XE worth the money? 

Maybe this is best answered by looking at the competition, Futaba and Spektrum and their prices on comparable radios. Is it worth the extra money over the FrSky X20s? For a field flyer I would probably say no, just get a bolt on tray for your X20s if you need one. If you want to be able to add extra input controls, monitor control inputs through multiple screens, need a larger form factor then yes it is worth it. In my experience larger 3 axis gimbals on smaller radios are very fiddly but they really suite the FrSky Tandem XE

I will get some videos of the radio in use with the Terminator T-1 build over the next few weeks uploaded to our YouTube chanel.