Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Too close to call - Arron said 'low inductance' first though. I am just happy to have the problems solved and I can now make a second inductor and get back to working on the chassis. It would be really good to finally have this running for a demo at the next event on the 29th. I don't know when I will put it in the competition as I still have some ideas for the wedges. The Sidewinder has a really neat adjustment called Slew Control; it's basically simulated inertia and it looks useful for correcting twitchy steering. I am very keen to see how that and the current limiting goes... _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Mon Apr 10, 2006 10:03 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
i'm calling this one
Thu Dec 29, 2005 8:44 am
dear god what was i doing up at that time???
If you have any low inductance motor (like say a thingap) adding inductance to the circuit could help your speed controllers out no end.
followed up by nick
quote:
@ Jake: That just reminded me that the hingap people have an inductor board in their catalogue; I will check it out
still be interesting to put an IBC on it and play with the frequency.
one side of my IBC is probbly still working.
@prong nick can only drive one bot.... i'd rather he had a slew of non lethal ones to choose from ;-> _________________ Mechanical engineers build weapons, civil engineers build targets
Mon Apr 10, 2006 10:09 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Filed & forgotten, I am sorry to say . If the Robot Power guys get back to me, I will find out the switching frequency; perhaps we can change the clock freq. on the Sidewinder. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Mon Apr 10, 2006 11:31 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Progress:
With the main electroncis sorted out, I moved on to the battery and BEC for the logic circuitry. This uses a pair of tiny LiPo packs to get 14.8V, which the BEC reduces to 12V. It should power the Sidewinder for a solid hour on a full charge. I protected the battery in several extra layers of heatshrink and the combined parts will be wrapped in foam later as well; no LiPo fires for me .
I realised I didn't have a good power switch for this, which is essential as the BEC is drawing current whenever it is connected. A pushbutton microswitch sounds best - something that will not turn off during an impact. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Tue Apr 11, 2006 2:24 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Progress:
I finished the frame yesterday and fitted the motors and wheels; they still need some work but everything goes together in the right places . I tried sticking Subliminal to the steel roof but unfortunately the magnets are not quite powerful enough to keep it there - it's close and a four wheel version would definitely drive upside down.
Subliminal is resting on a spare tile from the Marayong arena; as you can see its basically the same size as the tile. Not much thicker either!
There is still plenty to do: mount the roller ball(s), finish the BEC, mount all the electronics, and more... _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Thu Apr 20, 2006 5:37 pm
Nick Experienced Roboteer
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Has is really been three months since the last update? I'm SO slack! This week, I decided to upgrade Sub in order to take it to RoboGames 07. It is severely under weight and the obvious thing is to make the wedges thicker. I can go up to 3.18mm (1/8 inch) titanium plus add a second angled deflector to the wedges and still just stay inside the weight limit.
The next possible upgrade is LiMn batteries. Sub only runs on 12 volts, so a small 3S pack weighing just 350 grams will do the trick and extend the run time considerably. The current packs weigh 884 grams, so that is a welcome 534 g reduction. If these packs had been around when I designed Sub, I would have been able to make the frame considerably smaller and lighter
The existing thinner wedges won't go to waste: They just happen to fit on Jolt with a small amount of modification. I instantly have four spare wedges
The last mod may be to buy Sub a 2.4Ghz reciever. My old 75MHz radio is probably legal over in the US but the extra reliability of spread spectrum can't hurt. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sat Jul 22, 2006 11:08 pm
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
I forgot how cool it looked
Are you sure you still want the top bit protruding like that for robogames?
Methinks if you did get under an undercutter it would just go straight into the UHMW _________________ ( •_•)
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
That's exactly what I was thinking. My plan has always been to have some sort of deflector at the back of the wedges - a steeper mini wedge if you will. It looks like it will work in CAD and the next thing is to make an aluminium one as a test. The hard part is getting the mini wedge attached; I figure the strongest thing is welding, backed up by some small aluminium blocks. Sounds good, but nobody has had Ti welding done and the local quality may not be up to US standards. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jul 23, 2006 12:21 pm
dyrodium Experienced Roboteer
Joined: 24 Aug 2004
Posts: 6476
Location: Sydney
Ah yeah I remember now. Cool _________________ ( •_•)
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
#%$&%*(
Thanks for the tip Aaron, even if it is really bad news. I gues I will just have to send mine back and get in the queue. I wonder how it took so long for the fault to be noticed? The Sidewinder is around a year old now and it seem hard to miss something like that. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Joined: 16 Jun 2004
Posts: 11802
Location: Sydney, NSW
Good spellung costs extra around here
I talked to Chris Baron @ Robot Power and he was completely up- front about the problem (plus a generally great guy). I can send the Sidewinder back for an exchange, which must be costing him a fortune! It's a shame there had to be a problem in the first place, but I can't think of another ESC maker who would have handled it as well - zero weaselling and a helpful, speedy reply. _________________ Australian 2015 Featherweight champion
UK 2016 Gladiator champion
Sun Jul 30, 2006 11:58 pm
Knightrous Site Admin
Joined: 15 Jun 2004
Posts: 8511
Location: NSW
Robot Power has a good reputation in the bot community and on the OSMC project boards, so I believe it would be in there best interest to suffer the costs and keep their reputation and stay in the game for years to come.
On other news, Robot Power is now moving away from the good ole IRF1405 FET to a newer IRF3204 FET... _________________ https://www.halfdonethings.com/
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
RoboWars Australia Forum Index
-> Builders Reports
. If the Robot Power guys get back to me, I will find out the switching frequency; perhaps we can change the clock freq. on the Sidewinder.
.
. I tried sticking Subliminal to the steel roof but unfortunately the magnets are not quite powerful enough to keep it there - it's close and a four wheel version would definitely drive upside down.
(For once hahaha)