pic: 222 3 speed closeup/cutaway

[henryBsick]

Originally Posted by CJO

Correct me if I'm wrong, somebody, but I thik the whole SCS thing was to add sensors to the transmission so that the computer would keep it in the most advantageous gear at all times, similar to the transmissions on most cars.

I understand that something would be done to monitor the rpm's or another measurable function that would contribute to the horsepower. They would then shift up/down to get max. horsepower. The only thing was the specifics of the sensor. Where to put, what kind etc.

[tkwetzel]

Correct me if I'm wrong, somebody, but I thik the whole SCS thing was to add sensors to the transmission so that the computer would keep it in the most advantageous gear at all times, similar to the transmissions on most cars.

I understand that something would be done to monitor the rpm's or another measurable function that would contribute to the horsepower. They would then shift up/down to get max. horsepower. The only thing was the specifics of the sensor. Where to put, what kind etc.

The SCS was to be able to synchronize the gear and shaft. Automatic transmissions already put it into the most advantageous gear at all times. The SCS would lower or increase the power to the motors so that the gear selecting shaft would be running at the same speed as the next gear it is about to select prior to actually engaging the gear. It would cause less stress on all the components and give you smoother shifts.

[henryBsick]

Originally Posted by tkwetzel

The SCS was to be able to synchronize the gear and shaft. Automatic transmissions already put it into the most advantageous gear at all times. The SCS would lower or increase the power to the motors so that the gear selecting shaft would be running at the same speed as the next gear it is about to select prior to actually engaging the gear. It would cause less stress on all the components and give you smoother shifts.

I see now. Thankyou. There would be two set of sensors, and they would match rpm of the input shaft to that of the output shaft.

Great system but I see one probem with that. The shift wouldn't be exactly insantaneous, it would wait for shaft speed to = then shift. If a robust enough tranny is built i see no need for the matching of speeds, other than smooth shifting. Ours now is pretty smooth though thanks to the springs on the shifting rod. I have slammed it from 3rd into 1st many times (just to make sure) and it has skidded, I wasn't on carpet all the time, but it could take the throw of the ratio change. I still like both ideas though . / thinks to self/ there is an offseason for a purpose /done thinking/

[tkwetzel]

The shift wouldn't be exactly insantaneous, it would wait for shaft speed to = then shift.

That is a very good thought, but without any load on the motors, the speeds would match very quickly and it would still shift rather quickly.

[henryBsick]

Originally Posted by tkwetzel

That is a very good thought, but without any load on the motors, the speeds would match very quickly and it would still shift rather quickly.

Yeah, oops, forgot about the neutral positions. It would require servos or some other sort of multi psitioning shifter instead of our 1,2,3 pneumatics.
/Learns more and more each day. /

[tkwetzel]

/Learns more and more each day. /

That is what FIRST is about!

[CJO]

Team 254 used the same sensors on their drive shafts this year as are used on cnc mills to determine table position (I forget what they're called)

~Christopher

[team222badbrad]

It would be cool to have an automatic shifter but I do not see the need for it.

I doubt a servo would last very long if it were used with our trannies. If it was stalled while the holes were not aligned it might hurt the little motors. The servos would also require very accurate maching methods for the shift rod and also require very good programing to align the shifting rod with the ball bearings.
However a servo could probably handle the job.