Oars – They’re not sticks, they’re springs – by Howard Aiken

Most club rowers, quite rightly, will work with whatever equipment they are given, so we sometimes miss the subtleties of design in that equipment.  Take a modern sweep-oar for example. It is actually a highly-engineered precision instrument designed maximise the efficient transfer of mechanical energy from rower to boat, so to get the best out of them it helps if you understand its characteristics.bendy

In mechanical terms, each oar or blade on a moving boat is a second class lever with the fulcrum (centre of rotation) near the tip of the spoon.  However, while it is correctly described as a lever, a blade is not rigid. It is designed with a carefully calculated degree of flexibility.

From the rower’s point of view the importance of this flexibility is its relationship to the effort (energy) the rower is applying to the blade.  At the start of a stroke (the catch) the blade is subject to a bending force as the rower pulls the handle toward the bows.  The spoon remains almost stationary in the water, moving the boat forward by means of the force which is transferred to the boat at the pin.  As the blade bends it is in effect storing energy which will be released again as the blade unbends.  So the important question is – when does the blade unbend? There are only two options:

Option 1. The blade unbends as the spoon lifts out of the water.  In this situation the rower is pulling hard on the blade as her outside hand moves downward to extract the blade.  There is still pressure on the front face of the spoon as it leaves the water.  At its worst this is referred to as “washing out”, where the spoon doesn’t actually stay in the water for the full length of the drive phase but moves up and out of the water, creating a telltale “wash” of foam as it leaves the surface, rather than the puddle we should expect. In less severe cases it still produces a splash at the extraction – a sure sign that energy is being wasted in throwing water into the air rather than moving the boat.

Option 2. The blade unbends in the water.  In this situation the rower has slightly eased off the pressure on the handle at the finish.  As the blade unbends, the energy stored within it is transferred to the boat as forward motion. There will be little or no splash at the end of the stroke as the blade is extracted from the water because there is no pressure left on the front of the spoon to throw water into the air.

In practice there is only a small fraction of a second’s difference between option 1 and option 2, but that small fraction of a second can deliver a significant improvement in efficiency. Leaving the spoon in the river for that extra moment allows the rower to convert the energy stored in the blade into additional forward motion.  Over the duration of a race, that additional motion could be the difference between winning and losing.  In my experience, once rowers learn to think of the blade as a spring rather than a stick and to look critically at their extraction technique for signs of splash or wash, they can significantly improve the efficiency of their stroke, getting a little more boat speed for a little less effort by making better use of the flexibility that the designers of modern blades have gone to so much trouble to provide.

Incidentally, all of the above also applies to sculling, although being shorter in length, most sculling blades will not bend as visibly as a sweep blade during the stroke.

Carl Douglas Racing Shells – not traditional boat-building, by Howard Aiken

The modern sport of rowing is blessed with some fine boat builders aroundcdrs the world. They are devoted to the sport and work hard to bring their customers the best equipment they can make. And yet – I have sat in boats with sharp slides which cut the skin on my calves, I have coxed eights with rudders the size of a credit card which simply don’t work and I have seen a blow from the tip of a passing blade open a long scar on a boat’s skin, deep enough to keep it off the water for weeks. All of these things I have accepted as normal, because “that’s just the way things are”. Well, let me introduce you to a boat builder who doesn’t believe “that’s just the way things are” and has built the boats to prove it. Carl Douglas (http://www.carldouglasrowing.com/) brings to his work an insistent focus on “fitness for purpose” and he won’t allow a product out of his workshops if it fails that test.

Carl Douglas Rowing Shells (CDRS) builds high performance singles, doubles and pairs. His high-tech moulded wood composite shells typically have a glossy wood-grain finish but it would be wrong to call them wooden boats. They are as stiff and as weatherproof as 100% composite boats, and they are built to win races – which they do, regularly. Unlike 100% composite boats, a Carl Douglas shell won’t damage easily and as a result has a longer useful life.

Wood + Kevlar® = Strength (and beauty)
CDRS composite construction technology uses wood, laminated with Kevlar® and epoxy resin under heat and pressure. Carl argues that wood has evolved over 400 million years to withstand stress, fatigue and shock and is strong, durable, stiff, light and mouldable. While he can produce a standard white (or black) finish for clients who wouldn’t be seen dead in anything which looked like a wooden boat, he clearly enjoys crafting the outer skin of his shells to highlight the natural beauty of wood. While the glowing quality of the finish he and his team achieve has an undeniably old-fashioned look the technology he uses would have been unavailable fifty years ago and his team is one of the very few who can combine the hand-crafted sculpting of real wood veneers with the computer-controlled precision of 21st century hull design. Clients can choose from a wide range of customised woods, including Rosewood, Maple, Walnut and Mahogany and they can even get personalised designs inlaid in contrasting colours. Carl Douglas Racing currently has the capacity to build about fifty boats a year and each boat takes approximately three weeks from start to finish.

Re-engineering, from stem to stern
His racing shells are however, only part of the story. Carl is a Chartered Engineer and brings an engineer’s analytical approach to all aspects of boat design. This has led him to redesign many ‘standard’ boat parts to the point where everything from the bow-balls to the riggers, fins and rudders on his boats are now his own designs, and if you are willing to listen he can explain in layman’s terms exactly why each of the innovations he has made improves the competitive performance of the boat.

One example I found particularly illuminating was his AeRowFin© fin/rudder system (Figure 1). His innovation was startlingly simple. Whereas most boat makers are happy to fit fins and rudders cut from a flat sheet of metal, Carl’s design has an aerofoil profile (teardrop-shaped like the cross-section of an aeroplane’s wing).

aerowfin

Fig.1 AeRowFin© fin/rudder system vs. conventional fin/rudder system

As a result, it creates less turbulence when the rudder is used resulting in more responsive steering, lower drag and greater boat speed. It is such an obvious improvement to the basic design that I was left wondering how on earth other manufacturers have got away with selling such comparatively ineffective and inefficient fin/rudder assemblies for so long. See http://www.carldouglasrowing.com/sitedata/files/AeRowFin_tech_doc_3.pdf for more details.

He was similarly dissatisfied with the riggers other suppliers were offering for his hulls, so he designed his own. Carl Douglas riggers are, he claims, a better combination of lightness, stiffness and strength than his original suppliers could offer and moreover, they deliver these characteristics with a design offering lower resistance to both wind and water. He now supplies riggers and rudders for all types of sculling and sweep-oar boats. Both products were used on the GB men’s eight which won Gold at the Sydney Olympics in 2000.
More innovation (do you notice a pattern here?) can be found at the end of the riggers. While many coaches still adjust swivel pins with (carefully applied) brute force, CDRS has developed a precision non-slip mechanism for the independent adjustment of lateral and fore/aft pitches. I particularly appreciated the thought that went into the CDRS replacement for swivel height adjusting washers. They are bright red, so you can see one if you drop it on grass or on a landing stage, and they float, so you stand a chance of retrieving them if you drop one while on the water.
Seats and slides get the same treatment – properly thought-through designs so that the slides don’t cut your legs and the seats are still comfortable at the end of an outing.

So – do you own a CDRS boat?
The hard fact is that my club doesn’t own any CDRS boats (although some individual scullers do) and I have to ask myself – why? CDRS boats are certainly premium products and they don’t currently build fours or eights, but they are priced below their equivalents from the ‘big name’ manufacturers, and my club does buy their boats. In my discussion with Carl he reminded me of a saying I remembered from my previous career in Information Technology. It was “no-one ever got fired for buying IBM”, and I think that is the key to why CDRS build 50 boats every year rather than 500. Coaches and captains put their reputations on the line every time they buy a new boat. If they go with a big name and their squad still loses, no-one is going to blame the boat. If they buy a less well-known name (and bear in mind that most rowers don’t have a wide knowledge or understanding of boats and boat-building) then they risk being blamed for their choice when their squad loses. So they’ll pay more for the big name, because even if the rigging or rudder is not quite the best and it’s so fragile that it can be expensively punctured while being lifted onto a rack, most rowers won’t mind, because they’re sitting in a boat with a famous brand name. In the meantime, it’s the scullers and small-boat specialists who really know about hulls and rigging who buy Carl Douglas Racing boats. And ill-informed commentators and spectators will continue to be surprised to see these ‘wooden’ boats winning at regattas and head races around the world.

The company
Carl Douglas Racing Shells was founded in 1973 and is now the longest – established British boat builder. Over the past forty years, Carl and his team, based at the Harris Boatyard in Chertsey UK, have built an enviable reputation for the quality of their products and their service to customers. Their engineering-led practice has pioneered innovation in all aspects of boat-building from design to manufacturing and equipment. This and their expertise in computer-controlled machining has established them as a supplier of precision components to many of the ‘big name’ manufacturers. They build a range of high performance singles, doubles and pairs to their own designs in wood/Kevlar® composites, resulting in boats of outstanding ‘fitness for purpose’ – robust, reliable and beautiful to look at.

Some facts:
1. Each single takes between 120 and 150 man hours to build, depending on client specification
2. Pairs and doubles take about 50% more hours
3. The wood used is harvested only at the tree’s maturity and can be anything from 25 to 500 years old, depending on species
4. Building in wood means the boats are ecologically sound:
a) harvested at maturity, the wood used is efficiently converted into veneers
b) the exceptional durability of Carl Douglas boats gives them an exceptionally long working life
c) at end of life they are easily re-cycled into energy and safely re-usable by-products
5. A Carl Douglas single (including riggers) weighs 14kgs, a double weighs 25kg
6. Their wood is seasoned for 2 to 20 years before use
7. CDRS only use wood bearing FSC (Forest Stewardship Council) certification
8. While about 75% of a Carl Douglas shell is wood, they also use man-made materials including Kevlar®, carbon, glass fibre, resins, ultra-tough man-made finishes and metals – but always with the objective of maximising performance and endurance

For more information, visit www.carldouglasrowing.com

All images courtesy of Carl Douglas Racing Shells.

The offline version of this article was originally published in Issue 3 of Row360 Magazine row-360.com

Eyes in the Boat

Eyes in the Boat

I was recently asked to write an article for a new rowing magazine* (Row360 – Row-360.com). The subject of the article was a new coaching aid developed in Australia called Sibi http://yepp.com.au/sibi At its heart, Sibi is an array of rigger mounted high speed (100 frames / second) video cameras which monitor rowers and their blades during an outing. The hardware is backed up by some very clever software which allows coaches capture, edit and manage the images they need from this array without spending hours on a PC.  It tied in very well with my last blog post on the use of smartphones in coaching (Regattas and telephones – are you making best use of them?) although mainly to show how much more we will be able to do with purpose-built video systems rather than general purpose smartphones.

Here’s the full version of the article:

Eyes in the Boat – An Australian Innovation

If there is one technology which has enhanced the coach’s life over the last few years it is digital photography.  Whether as video or stills, digital photography has allowed coaches to hold up a mirror to their crews and say “THAT’S what I’m talking about”.  From smartphones to Go-Pro cameras to professional video equipment, there’s a price point for every club and every crew.

This year, an Australian company called YePP has taken the next logical step and is marketing a product designed specifically for rowing (called the sibisystem – sibi is short for “see it believe it” yepp.com.au/sibi ) which allows coaches to capture each individual crew member, simultaneously, at 100 frames/sec, during a session, from multiple, dual-lens cameras mounted on the boat.  Given the sheer amount of video ‘footage’ their system can create, they have wisely added comprehensive video editing and analysis software as part of their product.  So now, in addition to capturing the coach’s eye view from the bank or launch, coaches can record much more detailed close-up, stroke-by-stroke video of each rower’s performance.

Controlled via an sibicleansmallintuitive iPhone app, training requirements are minimal and crucially a recording can be triggered after an event occurs (catching a crab for example) allowing the coach to collect video from before, during and after the event from all cameras simultaneously with a single ‘trigger’.

When I first heard about it, I must admit I thought this was probably an “elite squad only” product, but in fact schools have been among the first users – and potentially in any rowing club which doesn’t have enough coaches to go round or where coaches also have to cox their crews (my least favourite coaching option) this product could be a real game-changer.  While the coach can continue to provide real-time feedback, YePP’s sibisystem provides indisputable objective evidence as to how the rowers and blades were working during  a session – both in terms of individual technique and their timing with the rest of the crew.

The user’s view

For those of you who are interested in the technical details of the cameras there’s a webpage here: yepp.com.au/sibi/camera.  However, I was more interested in discovering what the coaches and rowers who had used the system thought of it.  I was able to speak to two users on YePP’s Early Adopter Programme from Melbourne Girls Grammar, namely Christian Neeson, Director of Physical Performance and Health, and Lachlan Beckett, Head of Rowing.  Melbourne Girls Grammar have a history of innovation in rowing, having put the first girls crews out on the Yarra River as early as 1905.  Not surprisingly therefore, they were among the first to use video recording as a routine part of their coaching repertoire and as early as 2010 were experimenting with GoPro cameras attached to boats, blades and coxes heads.  While they got lots of useful footage from the cameras, coaches also discovered the practical limitations of the technology and the hours of time it took to review and edit the material placed real constraints on how often cameras could be used.

Working with YePP allowed them to make a major step forward in their coaching.  In Christian Neeson’s opinion “the ease with which we can ‘time-travel’ through the record of an outing makes a real difference and as a bonus we’ve also saved on the costs of having people following the boats with cameras”.  With 120 athletes to look after, he now has an archive of individual recordings for much of the squad which can be reviewed with coaches, parents and the athletes themselves.

sibiappgood

As Head of Rowing, Lachlan Beckett is responsible for a team of 36 coaches and uses the sibisystem to track the progress of individual coach’s training plans.  He also feels it has changed the way they coach. “Traditionally, coaches would spend time during an outing sorting out issues of technique with individual rowers.  This would occasionally lead to rowers feeling ‘picked on’ or neglected – which is certainly not what you want in a school environment.  YePP has allowed each rower access to an entirely objective record of their own performance, annotated if necessary by both their coach and themselves, which they can own and which can form the basis of a more obviously equitable teaching environment. So they’re happier, more proficient technically as rowers and more competitive as a result.”

SibiSystem  – Overview

Unlike general purpose video products, the Sibisystem has been designed for rowers and no-one else.  The cameras are not just waterproof, they are designed for simple attachment to racing boats and their two lenses capture synchronised video of both rower and blade.  With up to eight synchronised cameras (16 views) per boat coaches can capture up to 200×15 second sequences at 100 frames/second during an outing, triggered from an iPhone app.

The hardware is controlled by an integrated suite of software designed around coaches and rowers. Video archives can be maintained for each individual rower and annotated by both coach and rower.  Recordings can be compared to show progress over time. The system is self-contained and needs no additional IT infrastructure other than in Internet link. The current version of the product is based on five years of research and development and additional features are in the product pipeline for future release.

YePP have a team in place to support both the ongoing development of the product and the successful deployment in clubs around the world. With the financial capabilities of most rowing clubs in mind, they have designed a purchase plan based on a small up-front payment followed by an ongoing monthly fee.  For this each customer gets 8 dual-lens Cameras, 4 Bridges, 1 Hub, accessories and 98 User licences.  The fee includes all upgrades and new releases.

Is it for you?

My guess is that the coaches who will make best use of YePP’s sibisystem are probably (like Melbourne Girls Grammar) already routinely using video and photography as part of their coaching toolkit.  They will most appreciate the step up in capability that it provides and their rowers will gain the greatest competitive advantage from it.  And to rowing clubs and coaches out there who aren’t using video yet, the message is “look out”, because coaching is changing – and YePP’s sibisystem is setting a new benchmark for the coach/rower relationship.

Full product descriptions and technical details are available on the company website at http://yepp.com.au/ .

*This is a longer version of the article published in the September/October 2014 edition of Row360.

Regattas and telephones – are you making best use of them?

If you heard that another club had been gifted hundreds of pounds of communications and video equipment, you might think they were really lucky – or clever.  If you were particularly highly motivated you might even make enquiries as to how and from where they got hold of such a valuable resource.  Well here’s the thing – that club is your club and the equipment is there now waiting for an imaginative coach to use it effectively.

I’m talking of course about smartphones.  Most of your adult rowers (and quite a few of your juniors) have one – so if you are taking a squad of say 12 rowers to a regatta, you have more than enough equipment to boost your club’s overall coaching effectiveness by a significant margin in a very short time. Samsung

Even an average smartphone is today capable of shooting video (and stills) good enough to be used for training purposes and their built-in communications capabilities make it relatively easy to collect that video material together for the coach(es) to use.

Try this for a scenario.  You have an eight competing over a 1km river course.  The course has a bend in it so there is no one place from which you can see the whole race.  Apart from the eight rowers in the boat you have four others and yourself to make a video record of their performance.  You can communicate with them by calling them or via text messages.  Texts can be sent to individuals or to the group (a ‘how to’ explanation for group texting is available here: http://bit.ly/1kmUeWC).

As the start is furthest away, you take that station and position yourself so that you can record the start sequence.  You put your next camera about  300m down the course.  They will be able to record how the crew settles into race pace.  You put another at the half way mark and another 150 – 200 metres from the finish.  That still leaves you one spare to capture the finish even though that probably has less training value that the other stations.  Each phone only needs to capture about a minute’s worth of video – well within the capabilities of a smartphone. After the event and from the comfort of their own homes, your squad can upload their videos to your chosen online storage service (Microsoft OneDrive / Google Drive / Dropbox – there are lots to choose from) from where you can gather them together to review, edit and either email to your crew or replay at the clubhouse when you next meet.

If this sounds technically challenging, don’t worry.  The younger members of your club have all of the required skills to make this work. They are already doing most of it already, although probably for less useful purposes.  That said, as with any new exercise, it is worth rehearsing this on your own stretch of water before you try it out at a regatta.

A couple of words of caution may be appropriate here.  Recording video on a smartphone while riding a bicycle may not actually be illegal but it is certainly high risk and I’d advise against it. Don’t ask your squad members to risk their phones or their safety in pursuit of a training video – most phones are not waterproof and can break if dropped. However, as I said at the beginning, equipment and capabilities which were fiction only a few years ago are now available to us all.  It is up to us how we use it.

The Crab Conundrum

For many rowers in their first couple of competitive seasons, “catching a crab” is the biggest fear in the boat. After a while, as your most recent crab recedes into history and becomes a distant memory, rowers tend to stop worrying about it – until suddenly one day for no obvious reason, it strikes again.  Crabs are rare among senior rowers, but not unknown. They happen during the Oxford / Cambridge boat race, at national championships and at Henley.  So here’s the conondrum, why does this novice error occasionally strike even very experienced crews? And what should coaches do about it?

This video – big thanks to WA Rowing Club, Perth – shows an experienced crew catching a crab (crab at 1:42 NSFW – loud music):

 

There are actually two types of crab.  The ‘common’ crab happens during the power phase of the stroke when the rower is unable to extract the blade from the water.  The speed of the boat pushes the handle of the stuck blade into the rowers body.  If they are lucky it simply knocks them flat and passes over their heads.  If they are unlucky, the handle can lift the rower out of his or her shoes and eject them over the side of the boat.  The other type of crab (as shown in the video) happens during the recovery when the blades are, or should be, in the air. If the leading edge of a blade catches the water at the wrong angle, the blade enters the water, the suddenly increased drag stops the forward motion of the spoon and again the movement of the boat brings the handle towards the bow, striking the rower’s body with the effect described above. From the coach’s point of view it is important to know which type of crab a rower has caught as the remedies differ.

The cause of the common crab is usually that the blade is not square in the water, either because the catch was not square or because the rower was feathering the blade underwater. Both of these novice errors can be fixed quickly and simply if timely action is taken by the coach. Unfortunately, a common response from novice rowers trying to avoid catching a crab is to pull their finishes lower into their laps in the belief that this will help get their blade out of the water. What this actually does is to lower their rigger toward the water at the extraction, giving them less space to ‘tap down’ into – so the problem of getting the blade out of the water actually gets worse. Pulling the finish higher, so raising the rigger and creating more room for the tap down is actually the more effective response.

A crab on the recovery is often caused either by over-feathering or (particularly with novices) by failure to keep the knees down during the first part of the recovery.  If the knees come up early, the hands have to rise to get over them – and if the hands rise then the spoon has to drop toward the water. Again both these errors are relatively easy to fix by appropriate coaching if they are spotted in time.

Some coaches train crews to row their recoveries with blades very close to the water. Personally I’m not sure that this offers a real performance advantage, but it does increase the risk of a crab if the boat hits rough water or the wake of another boat.  I coach crews to use the same hand height  on the recovery whether they are using square or feathered blades.  This gives the boat a margin of safety should the conditions require it.

For most rowers, catching a crab is not a predictable occurrence.  It happens suddenly and unexpectedly and even the rower concerned my not be sure at which stage of the stroke the crab happened.  Without video evidence, diagnosis and specific remedial coaching can be difficult.  In these situations it is important not to exaggerate the problem in the rower’s mind.  A rower who is concentrating on not catching a crab  is probably not rowing at their best and the more the coach focuses on the crab the more pressure the rower is under. That pressure is more likely to lead to further errors and you risk creating a vicious circle. No-one catches a crab deliberately and I believe that the most common cause is a lapse of concentration – possibly elsewhere in the boat.

With senior crews I simply ignore the occasional crab.  If it isn’t due to basic errors of technique then you do more good by sticking with the training plan for the outing rather than chasing what can be a very elusive error.  Particularly in the run-up to a competition, good crew morale and the achievement of the right balance of attention and relaxation is more important.

It IS important always to check the rigging after a crab – particularly if it happened while the boat was moving fast.  A crabbed blade can bend rigging out of shape. If the crew are sharing boats it is also worth checking that someone else hasn’t changed rigger heights, spans or blade pitches – again possibly on a different seat.

Provided that the problem isn’t in the equipment or the technique you have taught, I think catching a random crab remains one of rowing’s ‘black swan events’.  Bad luck if it happens to you, good luck if it takes out the competition.  As a coach, you just have to live with it.

A favour requested

To those of you interested enough to read this blog – I have a new website for rowers and coaches under development at CrossedBlades.com.   I would be very grateful if you would join me in the development process by taking part in a very brief (2 minute) survey on our Facebook page at: http://bit.ly/1vCBO3A .

Thanks and best wishes,

HowardtheCoach

Google+

Novice Rowing Errors – “The Fist of Hur”

For some reason, a significant proportion of college rowers seem to have learned their rowing technique from the movie “Ben Hur” .  In this clip, you can see why this might be a problem:

From a host of other possible issues I want to focus on what I have called ‘The Fist of Hur’. While I can’t comment on the historical accuracy of the scene, the movie presents us with galley-slaves “rowing” with oars of such size and weight that they could have been carved from tree-trunks.  Just to move these oars at all needs enormous strength and a vice-like clenched-fist grip – in short, The Fist of Hur!

A brief experiment will tell you that clenching your fist tightens your wrist joint and the tighter you clench the more rigid the wrist becomes.   Tension and rigidity can also be caused by nervousness, but whatever the cause, they are a real obstacle to the smooth, responsive and accurate movement required in rowing.

Unlike the oars shown in Ben-Hur, modern rowing blades are high-tech precision-engineered instruments.  They are a careful balance of  lightness and strength, crafted to enter and leave the water during the stroke with a minimum of effort. In rowing as in many other sports, relaxation is fundamental to successful learning and one of the most important changes any coach can bring to a new rower is the relaxation of the clenched fist.

Very occasionally a rower will look at me as if I’m crazy when I ask them to unclench their fists and just hook their fingers over the blade handle.  They are fighting to control the blade in their clenched fists and can’t even imagine that they can control the blade with relaxed hands.  I sometimes get these rowers to row with just the finger and thumb of their outside hand encircling the end of the handle.  This brings home to them how to work with the equipment rather than fighting against it.

If practising in the boat is too challenging,  relaxed hands can be coached on the erg (rowing machine) where rowers can learn that holding the handle with the last two joints of the fingers is entirely adequate even for firm pressure rowing.

You can try the hand position as follows: 1) make a ‘thumbs-up’ sign 2) extend and spread the fingers into a ‘hook’ 3) turn the hand palm downward – and there you have the ‘relaxed hands’ position.

In coaching circles, rowing with the blade clenched in your fists has traditionally been called ‘blacksmithing’.  This is in fact a bit of an insult to all those blacksmiths who do extraordinarily precise work which does not involve bashing large pieces of iron with massive hammers: