Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[malcolmfrary]

the engineering problem is providing an interlock which guarantees this for a low cost...

If the reverse is "below" the stop point on the throttle stick, the interlock is more or less built in.  You have to get past the stop point to get to reverse. 
If the reverser was on another stick, it would need some electronic gating at the boat end, or, if a two axis stick on the transmitter, a slotted overlay on the transmitter LH stick to prevent reversing anywhere other than at stop.
With the "More power, Igor!" type switch, it "just" needs for the aux servo to set off a windscreen wiper type drive arrangement to cycle to one state or the other.  Maybe two pieces of copper clad printed circuit board sliding over each other could do the job and be more compact?  I see a need for care - in this case making sure that a) whatever arrangement costs less than a commercial one, and b) doesn't sink the boat.

[dodgy geezer]

If the reverse is "below" the stop point on the throttle stick, the interlock is more or less built in.  You have to get past the stop point to get to reverse. 

If the reverse is "below" the stop point on the throttle stick, you don't have a problem, because you already have a reversing ESC! This (albeit slightly tongue-in-cheek) discussion is about how to convert a non-reversing ESC to a reversing one using mechanical switching of the motor leads (either brushed or brushless) with another channel....

If the reverser was on another stick, it would need some electronic gating at the boat end, or, if a two axis stick on the transmitter, a slotted overlay on the transmitter LH stick to prevent reversing anywhere other than at stop.

Now that, I like! The left stick would have a 'U' shaped guide cut out of paxolin and screwed over the gimbal. The throttle would work with the 'aileron' channel hard right, and you could only go hard left by dropping to the bottom...

With the "More power, Igor!" type switch, it "just" needs for the aux servo to set off a windscreen wiper type drive arrangement to cycle to one state or the other.  Maybe two pieces of copper clad printed circuit board sliding over each other could do the job and be more compact?  I see a need for care - in this case making sure that a) whatever arrangement costs less than a commercial one, and b) doesn't sink the boat.

Needs to be able to transmit a lot of power. And not spark, if the hull is wooden! Here is a shielded knife switch... http://www.ebay.co.uk/itm/32A-Two-Pole-Double-Throw-Knife-Disconnect-Switch-/160661908650?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item2568322caa

[dodgy geezer]

Here's a thought...

[Mad_Mike]

I like that 

[malcolmfrary]

If the reverse is "below" the stop point on the throttle stick, you don't have a problem, because you already have a reversing ESC! This (albeit slightly tongue-in-cheek) discussion is about how to convert a non-reversing ESC to a reversing one using mechanical switching of the motor leads (either brushed or brushless) with another channel....

What I meant was - on a forward only ESC, "off" is commonly "left stick as far back as it goes".  A reversing pulse would be given by driving the associated servo beyond that point momentarily.

For the TX plate I was thinking of an inverted "T", with the reverser part being pulsed one way or the other, but the "U" is better, giving a visual indication of what is going on.

The rotating or sliding PCB might take less driving effort, but its current carrying ability would be dependent on surface area and pressure.  A knife switch does benefit from long leaves on the sockets - adjustment is fairly critical, and longer (springier) leaves help that adjustment last longer.

[dodgy geezer]

In the drawing, the plug pins are pivoted on an insulating tube (not shown), and are soldered to the input cables. The pins can be driven by the two ends of a servo arm and move in opposition to each other - all that does is alter the wiring of clips compared to the pins moving synchronously...

But, of course, you cannot be sure that the pins will disconnect at precisely the same time from each clip - in theory a servo failure when only one was disconnected would leave the ESC in a dangerous state....

What I meant was - on a forward only ESC, "off" is commonly "left stick as far back as it goes".  A reversing pulse would be given by driving the associated servo beyond that point momentarily.

Sorry - didn't understand. Yes that would work...

A knife switch does benefit from long leaves on the sockets ...

..And you do get the benefit of an Igor (Yes, masterrr) ...

but I wonder what boats would benefit? Fast boats usually perform badly in reverse....  I suppose a cheap springer..... ?

The advantage of a 'U' shape is that you could limit the reverse speed by shortening one arm - here's a paper template example...