Ok, So I went home and tried my other controller receivers (I have two), however, They have 9 wires vs 6, like the lynxmotion wires, so I was confused on where those go! However, upon experimenting, I did connect the first 6 in sequence like the lynxmotion diagram, and that receiver responded! I didnt get the spider to move, which Im guessing I needed to have all 9 wires connected instead of just 6! So, now im more convinced that I burnt out the receiver somehow! I went onto lynxmotion and purchased another controller and receiver set! So, ill test that when it comes in!
Other than that, i know i have more tweaking to do as far as movement goes, but I have a question! When i connect the spider, it pops up, stands for a couple of seconds, and goes limp! Like in the resting position, how do I get the servos to hold their position? They arent that expensive, but they are decent as far as torque goes! Is it bc the metallic spider is just too heavy? bc id thats the case, ill just design the hexapod body and legs and 3d print it, it would be a crap ton lighter!
It would be good to make sure the controller is compatible directly and not requiring a higher voltage. Most of them can be connected directly but a few models use a higher voltage and can possibly cause electrical issues or simply not work with the BotBoarduino (without an adapter).
The Lynxmotion version of the library can be used with other PS2 controllers, too. We simply have a few fixes in it for our controllers specifically, but it should not prevent other controllers from working.
Well, we checked your servos (MG-996R) a bit online and found this. It does not look like they tend to be of high quality. Therefore, I’d recommend either changing the servos or using a lighter frame. The fact that they cutoff while being powered/receiving a pulse (from the SSC-32U) means a servomotor issue.
It would be good to mention that your servomotors seem to indicate they support 4.8-7.2 V, but most sources only mention 4.8 V DC and 6.0 V DC specs. Therefore, your power source might also be causing issues / damaging them.
The RC servomotors used in the Lynxmotion Phoenix 3 DoF hexapod kit are the [RB-Hit-29]. I have some here for tests that have been in use since before 2012 and they are still in working order.
So, if you decide to change RC servomotor, I’d recommend those as they can do the job quite well. These would have to be powered with 4.8-6.0 V DC, not anything above that.
If the voltage of the power source is an issue for you, you could do one of two things:
Change the power source to a 6 V DC one! A good fit for this is RB-Sta-08, which is a 6 V DC, 2800 mAh NiMH battery pack. The good things about this type of packs is that it can be safely discharged to empty. Since the BotBoarduino/SSC-32U does not include any under-voltage cut-off for the power source, it can easily drain a LiPo-based pack below its safe level and cause damage to it (therefore, monitor that!). You can use RB-Ten-02 for charging.
Add a DC-DC regulator to provide a stable 6 V DC to your VS1 input of the SSC-32U. Something like the RB-Pol-467 might be a good fit. It is a 6 V DC, 15 A step-down voltage regulator. It requires a minimum input voltage of 7.2 V DC. Therefore, your fully powered 7. 4 V DC battery pack should be just perfect for this.
Well, i have read that you could use other controllers and such! Ive seen videos of folks playing with their spiders using different controllers, but I havent found any diagrams on how to connect the 9 cable receiver to the Botboarduino, so i just took a chance yesterday and at least got the LED to display on the other receiver, which lead me to now believe that my lynxmotion receiver was busted, so im replacing it! I was get this right before branching off to other brands and stuff!
Lol, I should have know that robotics was gonna be an expensive hobby! ! So, what specs should I look for as far as torque, keeping their position, and pulse? Like I said, If I printed out the body and legs, that would dramatically reduce the weight, and should help, I would think, right?
I just trying to be frugal, i mean, 18 servos, at $28 a pop, might take about a little while to get! at least a month or so!
In the mean time, I should go ahead and get the 6v battery pack and charger, those servos do not last, lol! At least not what that amount of voltage! So, the voltage regulatory would correct my issue with my battery pack now? Thats awesome, Ill get one of those and hook it up first!
It is possible you got the VCC/GND of the wiring well (hence the powering up of it) but not the ATT/CMD/DAT/CLK wires. There are quite a few “official” color patterns for these (read: it feels like literally every version is different), so experimenting might be the only solution. It is only 24 permutations, after all…
Well, on paper, the Rb-Hit-29 have a lower maximum torque @ 6 V DC than the ones you have right now. The main difference is most likely quality of the components inside the motor, including the controller itself, the motor driver used, the gears and output shaft, etc. Specs wise, something similar to the RB-Hit-29 should serve well for larger 18 DoF hexapods.
For the less expensive, questionable quality servomotors, any weight reduction will be critical, I think. Even further, weight is by far one of the greatest issue with mobile robots. Wheeled robots have it easier due to low friction of moving wheels, but walking robots need to reduce total weight and payload as much as possible. Also, please keep in mind the duty cycle for hobbyist grade servomotors is very low. Therefore, they might overheat more easily (especially at 7.4 V DC!) and they need rest after 15-30 minutes of continuous use (especially if at or near their maximum torque). Please note also that many servomotors can product their rated torque but cannot maintain it continuously. This is a problem for walking robots, where the joints need to hold the weight continuously whether they are moving or not (to stay balanced).
Well, at least they are on special right now! Also, you may get a small rebate by buying larger quantities at once.
Well, by having a fixed 6 V DC, high-current output instead of the battery pack (which when fully charge is way above 7 V DC) will most likely help quite a bit.
Ok, So i got the new controller and receiver in, but I dont want to use the 7.4v battery to run the spider! I know you sent your suggestion, and I will do that, but can i get away with a 6v 1300mah battery pack for now? At least for testing purposes? Im currently in the process of setting up a 3d model of my current aluminum spider so i can print out an ABS plastic, remotely the same size, spider! I think that changing the weight, like we said before, with dramatically reduce the stress on the current servos, and will use less energy on the battery!
Also, do u think the Hitec Hs-322hd servos are good? Im not sure what Im looking for when Im reading the specs for these servos! I look on the MG996r, the ones I have now, their specs vs others, and they are roughly the same!
That should be completely fine. You just may not be able to run it for too long. As for discharge rates, it should be able to do up-to 2.6 A total, which may not be enough for 18 srvos moving quickly / all at once.
Indeed!
It may work, but as mentioned earlier, the 3 DoF hexapods for Lynxmotion use the RB-Hit-29 (HS-645MG), which has more than double the rated torque of the RB-Hit-67 (HS-322HD)
! So, what specs should I look for as far as torque, keeping their position, and pulse? Like I said, If I printed out the body and legs, that would dramatically reduce the weight, and should help, I would think, right?