Geartronics Paddleshift for sequential gearboxes

The most sophisticated & cost effective pneumatic

paddle shift system currently available...

Benefits

1. Faster, more precise gear shifts without use of the clutch - upshifts typically 50ms or less.

2. Ability to change gear mid corner with reduced risk of de-stabilising the car.

3. Virtually constant power delivery to the driven wheels meaning increased straight line performance.

4. Both hands can be kept on the steering wheel at all times.

5. Allows driver to concentrate on other aspects of car control, leading to reduced lap/stage times.

6. Potential to reduce gearbox dog wear due to faster shifts and reduced incidence of mis-shifts.

7. Reduced clutch wear - you're not using it except for standing starts!

8. On turbocharged cars, boost is not lost during gear shifts, leading to significantly increased performance.

Features in detail

1. Uses pneumatic actuation, as favoured by almost all professional race engineers. Unlike electric solenoid

systems, pneumatics offers the degree of mechanical compliance which is absolutely essential if you are

to avoid gearbox damage. Pneumatic operation offers an economical, versatile & reliable power source

and allows the use of very compact gearbox actuators. One of the greatest benefits of using pneumatics is

the ability to adjust the shift force to the requirements of the gearbox. Click here to compare the features of

air, solenoid and hydraulic actuators. As you can clearly see, large & heavy 12v solenoids have no place in

any serious paddle shift system.

2. Virtually seamless full-throttle up-shifts and clutchless down-shifts using our unique throttle blipper system.

During in-car testing we have achieved consistently rapid up-shifts in as little as 35ms and down-shifts in

the order of 100ms. Ignore the claims from other suppliers regarding shift times - if it's not closed-loop, it's

not the quickest! Our shift time claims are derived from real installations and come from our detailed on-

board datalogging within our GCU.

3. Extremely sophisticated GCU, featuring fully closed-loop control of the gear shift based on selector barrel

position. The majority of aftermarket paddleshift systems are 'open-loop' - essentially pull the paddle,

bang the lever and hope for the best! Using open-loop techniques is extremely dubious in such a dynamic

application as gear shifting. For a better explanation of why the Geartronics closed-loop system is

essential, click here.

4. Our GCU takes inputs from the following: gear position sensor, engine tachometer, throttle position sensor,

clutch position sensor, pneumatic pressure sensor and paddle switches. All analogue inputs feature 10 bit

resolution for greater accuracy.

5. Includes mis-shift safety strategies and a configurable retry option on up-shifts. Ask our competitors what

their systems do in the event of a mis-shift, if they tell you it never happens or they try to evade the

question then be vey sceptical!

6. Includes safety strategies to prevent the driver from performing potentially dangerous shifts, e.g.

attempting a down-shift which would result in the engine exceeding its safe rpm limit. All features

are included as standard and can be disabled in software if so desired.

7. Engine cut either by direct connection to ignition coils (or injectors) or digital interface to engine

management controller. No relays are required for the engine cut function and all switching is achieved by

solid-state electronics within the GCU.

8. Full on-board data logging of the following: gear shift count (up & down into each gear), mis-shift and retry

count for each gear, fastest & slowest shift time into each gear, maximum engine speed in each gear,

pneumatic pressure, compressor duty cycle & engine/gearbox runtime counter. All logged data can be

exported in the form of an Excel spreadsheet.

9. Includes gear position indicator and integral 4 stage shift lights, individually configurable upto 16000 rpm.

10. Full system includes: 12v automotive compressor, purpose designed accumulator (NOT an adapted fire

extinguisher bottle!), actuator & valve assemblies as required, conventional twin paddle assembly or our

unique 'rocker' paddle assembly allowing single-handed use, Fully closed-loop GCU complete with our

proprietary PC setup software, pneumatic throttle blipper assembly, wiring harness, all sensors &

fittings, comprehensive installation & setup instructions.

Click the images below to view a full-sized version.

http://www.paddle-shift.co.uk

Site constructed & maintained by Neil Wallace (Geartronics Ltd.)

Page last updated 22nd January 2008.

The system is available with various paddle options. Here we see our unique
'rocker' paddle assembly. Designed to be mounted between the wheel and quick
release boss, this system involves no drilling of your steering wheel and offers
the ability to shift up and down with just one hand.

We can also offer more conventional individual paddles for mounting directly to
the wheel. These neat and ultra lightweight assemblies are fitted with carbon
fibre flippers and have an extremely positive tactile feel.

Here we can see the actuator installation on the Zeus development car. The
prototype system originally used a separate valve block & actuator, but this car
now uses an integrated actuator assembly as shown. However, integrated
valves are not necessarily the best option for some applications. High levels
of vibration experienced by direct mounted valves can cause them to leak and
fail prematurely in some installations. The speed advantage of direct mounted
valves has proven to be negligible during testing, even with the prototype
pneumatics we had been able to achieve shift times in the order of 40ms.

We don't mind showing you what's inside our control box. On the contrary, we
are justifiably proud of our creation. Our GCU is specifically made for
paddleshift operation and is designed and assembled in-house. We don't use
an industrial logic controller and hide it in a fancy box! For the electronically
minded, the board uses multi-layer surface mount technology and is based
around a RISC microcontroller running at a clock frequency of either 20MHz or
40MHz. The analogue inputs feature 10 bit resolution and are sampled 10,000
times per second. This allows us to track the gearbox barrel position to an
accuracy of 1/3 of a degree!

Here is a screenshot of the configuration software. All parameters are user
definable and setup is achieved by use of our proprietary setup software. It
might initially appear complicated, but the reality is that gear shifting is a very
complicated business. The GCU features a detailed datalogging system
that allows the race engineer to fine tune the system. The GCU also has the
ability to perform auto up-shifting and down-shift 'pre-select'.

Actuator selection depends upon specific installation - the 'one size fits all'
approach does not allow for optimised reliability & performance. Here we see
an actuator assembly with integral valves that would typically be used inside
the vehicle with a direct connection to the existing gear lever. Some other
installations dictate that a separate actuator & valve assembly is used to
isolate the valves from the extreme heat & vibration that is often experienced
in a race car installations.

Our unique in-line throttle blipper assembly enables smooth clutchless down
shifts. The mechanism features full mechanical adjustment and damped
throttle return - essential for vehicle stability on down shifts. Other throttle
blipper options are available for specific applications where it's either not
possible, or not appropriate to fit a 'universal' blipper.

Here is an actuator that would typically be used on a transaxle installation in a rear
engine race car. The bracket you see in the photograph is for installation on a
Hewland FTR/JFR transaxle. This actuator requires the use of a remote valve
assembly as seen in the following photograph.

To see a short video of the system in operation, click the image on the left.
For slower internet connections use 'right click' and 'Save Target As...'

This was actually the first run of the prototype system in our Sierra test car!

Basic systems available from less than �2000 +VAT.

Professional system using bespoke actuators,
Goodridge hoses & aerospace specification wiring
harness, available for less than �4000 +VAT.

Another video clip, this time of the Zeus race car. Click the image to play
the video or right click & 'Save Target As...' to download it to your
computer (approx 3Mb.)

The system uses a purpose designed air accumulator so that the
compressor only needs to operate intermittently. The accumulator pressure
is controlled by the GCU via an extremely accurate pressure transducer. The
precision pressure regulator maintains the shift pressure at the desired level
so that each shift is executed with the same force, regardless of accumulator
pressure. The volume of the accumulator allows up to 15 shifts between
compressor operations.

This is a clip of a Gould GR55 hillclimb/sprint car testing the paddleshift system.
This car is fitted with a 700bhp Cosworth HB Formula1 engine and 6 speed
Xtrac gearbox. Instead of the usual compressor/accumulator air source, this car
uses a 1.1 litre rechargeable compressed air bottle that is good for several
hundred shifts before a re-charge is necessary. The paddleshift installation is
fully featured including TPS, RPM & clutch monitoring as well as a bespoke
throttle blipper for smooth downshifts.

The Zeus race car test bed again, this time testing an updated version of the
ECU control software. The banging you hear on upshifts is due to an ignition
only cut with a turbocharged engine. Normally aspirated engines don't usually
display the same characteristics. For the next test session we will experiment
with both an ignition and fuel cut to prevent the exhaust explosions!

or call 0114 2374102

The Geartronics remote valve assembly uses direct operating valves for
faster response times. The airflow that they can provide is adequate for
most installations and allows upto 5 down-shifts in around 1 second. The
Goodridge hoses seen in the photograph are used on our professional level
systems. More price concious installations have the option of using push-fit
pneumatic hose.

Throttle blipping for clutchless down-shifting is often one of the more
challenging aspects of an installation. Every car is different and we need to
cater for all eventualities. In the ideal world we would use a small cylinder
like this to operate the engine throttles directly.