Driving with Volvo Penta IPS Drives

We recently took delivery of our Ranger Tug R-43, Out Of Office, powered by two Volvo Inboard Performance System (IPS) Pod drives. The IPS Pod drive has been around for over 20 years and while many boaters have heard about it, many have not had a chance to experience it. In this article we cover our initial experiences with the various aspects of driving a boat with the Pod drives and the different drive modes available, including one that normally is not available on the Ranger Tug R-43. If you are more of a visual learner, we have a companion video showing how these drive modes work.

If you just want to know what we like about them, here is our tl;dr:

Joystick Driving is awesome. It is unlike any other boat control system. You have total control over the boat with one control. It is extremely intuitive and especially new boaters will likely take to it faster than they do a traditional throttle-and-wheel system.

We will drive the boat 95% or more of the time in Joystick Driving or Joystick Docking. If we didn’t have Joystick Driving we’d use Joystick Steering, but with it, there is no real reason to. Assisted Docking is useful when conditions are really challenging, but for most docking, Joystick Docking provides more than enough control for docking. For driving, Joystick Driving is a convenience that on a boat in this class is well worth the cost of the option.

If you are looking for a twin-engine cabin cruiser in the 40+ foot class, they will often have IPS drives at least as an option. We believe the slight risk associated with having Pod drives is well worth it for the ease of driving and docking. Just make sure the manufacturer positions the joystick for ease of access as you are seated at the helm. It does not make sense to get IPS drives unless you can actually use the Joystick. In addition, look for the Joystick Driving feature. It is worth the additional cost if it is an option. DPS and Assisted Docking is also worth it to help control the boat while waiting for the fuel dock to clear, if you are uncomfortable docking, or for use when fishing.

If you want to understand why we came to these conclusions, keep reading. 

Longer Version

What Pod Drives Are

While Pod drive systems differ substantially from conventional propulsion systems, the motor is just a standard Volvo Penta marine diesel motor; a pair of Volvo Penta D6 380 on the R-43. These motors are common in various drive systems. The Marex 330 comes with a D6 380 sterndrive, and the Nimbus 405 can be upgraded to two D6 380 shaft drive engines. Fluid Motion’s own Cutwater C30 used to come with a single, but more powerful version of the same block.

However, instead of connecting the motor to the propeller via a shaft, the drive system is a large nickel-bronze-aluminum alloy Pod mounted underneath the boat, connected to the motor through a large oval opening in the bottom of the hull. Now for the really cool part: these Pods rotate. That’s right, they spin. The IPS 10 series on the R-43 rotate 30 degrees to each side, i.e. a rotational arc of 60 degrees. This permits the boat to move in directions even differential thrust with a pair of twin engines has a hard time doing.

The Pods also have forward-facing counter-rotating propellers. Counter-rotating propellers improve efficiency and eliminate the yaw of a single propeller - the sideways thrust that you get when the propeller rotates. Having them facing forward further increases efficiency as the propellers operate on undisturbed water. We’re seeing about 2 nautical miles per gallon (nmpg) at hull speed, and about .68-.85 nmpg at any speed between 13 and 30 knots, which is not bad for a boat that is nearly 50 feet long and 14 feet wide!

The final cool part of the Pod drives is that Volvo has routed the engine exhaust through rear of the Pods themselves. Venting the exhaust this way carries it behind the boat when under way, which means you don’t have diesel fumes in the boat.

There are disadvantages though. First, unlike other forms of propulsion, a Pod can’t have a skeg, that little fin mounted forward of the propeller to protect it. Putting one in front of the Pods would defeat the purpose of having them operate on undisturbed water. They also have slightly deeper draft than a standard shaft-drive boat, but probably only by about 6”/15cm. The draft is 42”/1.07m on the R-43.

Differential Thrust

To understand just what the Pod drives can do, we need to briefly understand differential thrust on a multi-engine boat. Imagine you have a twin engine boat, and you run just the port engine forward. It will push the bow to starboard. If you run the starboard engine at the same thrust level in reverse, the boat will spin on an axis centered on the propellers, to starboard.

Now modify this by turning the rudder hard to port. Then, give the port engine slightly more thrust forward than the starboard engine has in reverse. The slight additional thrust on the port engine pushes against the rudder and forces the stern starboard, while the thrust on the starboard engine cancels out the forward movement. The result is that the boat crab walks sideways to starboard! This is differential thrust.

Many boats with twin (or more) engines, such as the Ranger Tug R-27 and Solara S-310, come with a joystick that automates this. The joysticks are connected to a computer that computes the right level of differential thrust, along with bow (and stern if installed) thruster power to move a boat in the direction you want.

Boats with IPS Pod drives also come with a joystick, but because of the Pod drives spin, these joysticks are more capable than those on a twin-engine outboard or inboard boat. They can move the boat in more directions, more smoothly, and also have some additional tricks. In fact, the R-43 does not come with thrusters because they are not necessary on that boat. (Note that many other boats with IPS Pod drives do come with thrusters though).

Driving an IPS Boat

The Volvo Penta IPS comes with a few components you need to be aware of. First is the Electronic Vessel Control (EVC). This is the computer that controls the Pod drive. You interact with the EVC using the joystick that’s installed at the helm station, and the Glass Cockpit. The Glass Cockpit is a screen installed at the helm that can display information about your engines, the boat, and even navigational data. The screen and at least some of the software on it are actually made by Garmin, so on boats with a Garmin helm, it integrates seamlessly with the helm. Some boats integrate it with other vessel control systems as well, allowing you to control things like the air conditioning. On the R-43 it is primarily used as a companion to the joystick.

Joystick Docking

The EVC combines differential thrust with the spinning of the Pod drives to give you several interesting features. The first is Joystick Docking. This is essentially a slow-speed joystick only driving mode that lets you control all movements of the boat using the joystick. You activate it by ensuring the throttles are in neutral and the helm station active, then you press the docking mode button (lower left).




With Joystick Docking you can move the boat in any horizontal direction by merely moving the joystick in that direction. It will be smoother directly forwards and aft, but you can also move it diagonally. To spin the bow to starboard, for instance, you twist the joystick to the right.

You can combine these movements, but small single movements work best. Once you let go of the joystick the engines return to neutral. As with a normal throttle the boat will continue in the last direction until the momentum you gave it is cancelled out preferably by you or water, not by the dock, and definitely hopefully not by crunching the fiberglass of another boat. You can move the joystick in the opposite direction of the movement of the boat to slow it or stop it, just like a normal throttle.

As with docking any boat, you should spend about 80% of your time with the throttle - the joystick in this case - in neutral and let the boat glide. However, using Joystick Docking you can typically dock the boat without ever touching the wheel!

Joystick Docking operates up to about 3 knots by default, so it is quite useful to drive the boat inside a no wake zone. If you need to, you can activate the “High Power Mode” by holding the docking mode button for three seconds. This is meant to compensate for high wind or current. To exit High Power Mode, press the docking button again.

Verdict

Joystick Docking is great! If you’re familiar with how to dock a boat, and comfortable with the fact that it keeps moving even when you let the throttle go, you will feel at home after a couple of attempts. Just like with a throttle, you can stop a movement in any direction by pulling the joystick in the opposite direction. It essentially combines the wheel, throttle, and thruster controls into a single very intuitive instrument. You can use it to maneuver in tight marinas and maintain great control over the boat. We routinely use it to maneuver our boat into a covered slip that is less than 1m/3ft wider than the boat.

Dynamic Positioning System

An optional feature on the Volvo IPS system is the Dynamic Positioning System (DPS). This is a station keeping function. DPS requires a separate GPS antenna connected to the EVC. It allows the system to know exactly where it is geographically and to stay exactly there! Think of it as a virtual anchor that compensates for wind and current.

With the throttles in neutral and no other functions enabled on the Joystick, push the DPS button to engage the system:




With DPS mode engaged, the EVC will hold the boat in the exact position and with the bow pointed in the same direction. This is a really useful feature while you’re waiting for the fuel dock, or waiting for salmon to bite on your mooching rig!

That’s not all though. If you look at the Glass Cockpit you will see that it changed screen when you pushed the DPS button. It will show a screen with a circle with a boat in it. That circle is a representation of where your boat is. You can reposition the boat 3 meters/10 feet forward, backwards, or sideways, by tapping the joystick fully in the intended direction and letting it go. It will beep, and the boat will move until it arrives where it is supposed to be, and stop. If you twist the joystick fully in either direction the boat will twist 5 degrees in that direction and then stop.

Verdict

DPS mode is great when you need to hold the boat still. We use it, for example, while waiting for shrimp traps to soak, and when someone else decides to drive into and take up most of the fairway as we are pulling away from the fuel dock. It is also useful for mooching or jigging, which is nearly impossible to do in Puget Sound without either putting a whole lot of weight on the line or anchoring. It’s also great when you are just waiting for a crowded fuel dock or pump out to clear.

Assisted Docking

If you need more precision than Joystick Docking can provide, or there is a lot of current and wind, Assisted Docking mode is your friend. It is an optional software feature that changes how the DPS mode functions and adds one more feature. It also uses the DPS antenna as your GPS Copilot and you activate it by pushing the DPS button. Just like the stand alone DPS mode, it has a station keeping function where the boat stays in place, and it also allows you to move the boat forward and backward.

However, Assisted Docking differs from both Joystick Docking and DPS mode. Unlike DPS mode, it has more granular movements. If you have the stand alone DPS mode, the sideways or forward/backward movement of the boat when you tap joystick is 3 meters/10 feet per tap. If you have Assisted Docking the movement of the boat is instead .5 meters or ~1.5 feet per tap. In addition, with Assisted Docking, you also get a Side Push mode that makes the boat push gently against the dock so that it stays in place while you get off to tie it up.

Unlike in Joystick Docking, where the boat continues to move after you let go of the joystick, in Assisted Docking, it will stop and stay where it is. You can move the boat by tapping the joystick forward, backward, or sideways, or you can do it by holding the joystick in any direction.

In other words, Assisted Docking is like Joystick Docking, but without the drift and with automatic compensation for wind and current. This makes docking really easy especially in challenging conditions. The boat will go exactly where you want it to go, and stop moving when you stop telling it where to go. It is the nervous captain’s best friend.

If you have the Assisted Docking software installed you don’t have a separate DPS mode. To determine if you have DPS, or Assisted Docking, or in some cases neither, tap the throttle icon at the bottom of the Glass Cockpit, click Full Function List, and it will enumerate which software functions are enabled on your boat. If you have neither, you would need to install a DPS antenna to activate them, but if you have the DPS antenna already, you can upgrade to Assisted Docking with a software upgrade.

To activate Assisted Docking push the DPS button. The Glass Cockpit changes again.
 

The circle represents your boat. Once the boat is settled in the center of the circle, tap the joystick either forwards, backwards, or sideways. You will hear a beep, the circle turns yellow, and the boat will start moving. It will move 0.5 meters (~1.5 feet) in the desired direction, and stop. If you twist the joystick and let go you will hear another beep, and the boat will twist four degrees. You can also move the boat any amount in any direction by simply holding the joystick in that direction.

When the boat is where you want it to be, next to the dock, and it has settled in that circle in the Glass Cockpit, push the joystick lightly toward the dock and push the “Side push” button on the glass cockpit screen:



The boat will now hold itself against the dock so you can get off and tie it up.

Verdict

Assisted Docking is designed to compensate for wind and current. If you frequently dock in those conditions you will likely find it helpful. We use Joystick Docking more, partially because we are in covered moorage where Assisted Docking will not work because the GPS antenna does not have a fix.

We often use Assisted Docking for the final approach and adjustments once we are in the slip. It is great for small adjustments of your position. It is slower than Joystick Docking but it is safer and more precise, and if you don’t need to go very far with it, it works great. However, docking from the fairway with Assisted Docking is quite time-consuming. We also find the side push useful, especially if you are single-handing the boat or if you are docking in wind or current.

Joystick Steering

Joystick Steering is exactly what it sounds like: you steer the boat using the joystick. Here’s how it works. First, use the throttles to adjust your speed the same way you would on any boat. Use the wheel if necessary to keep you on track, or tap the Heading Hold button on the Glass Cockpit. Then push the Joystick Steering button on the joystick:
 

If you weren’t already in Heading Hold, you are now. The boat automatically engages Heading Hold if it is not already engaged when you push the Joystick Steering button if no auto pilot course is engaged. You can now use the joystick to steer the boat. If you are already familiar with heading hold from another boat, you recall the > and >> buttons that change direction by 1 degree and 10 degrees? The joystick is analogous. If you twist the joystick and let go, you will adjust the heading one degree in that direction. If you twist and hold, you will gently turn the boat in that direction, engaging a new heading when you let go. If you push the joystick in either direction, you will rapidly turn in that direction. If you push and let go, it will turn about 10 degrees.

Verdict

Joystick Steering is a great feature. On some boats, the joystick is mounted in an awkward position forward of the wheel making it really impossible to use for this feature, but on the R-43, it is mounted ergonomically on the outboard side of the helm seat, allowing right handed drivers to very easily control the boat without touching the wheel. We do not use the steering wheel at all. Never have actually, and I am not actually sure when and why I ever would!

Unfortunately, Fluid Motion do not offer an option for left handers to get the joystick mounted on the left side of the drivers seat. I can definitely feel how this will be awkward for lefties.

Joystick Driving

At this point, I really want to extend my sincere thanks to Volvo Penta. The factory reps provided us an upgrade to Joystick Driving, which is an optional feature not included on many boats, including the R-43.

It should be.

Where Joystick Steering removes the need to use the wheel, Joystick Driving removes the need to use the throttle levers. In Joystick Driving you control the throttle with the joystick at all speeds, allowing you to completely control the boat with the joystick. For steering, it works exactly like it does in Joystick Steering mode. In other words, you now have complete control over every movement of the boat with just the joystick.

To engage Joystick Driving you leave the throttle levers in neutral and push the Joystick Steering button. The Glass Cockpit changes to a different screen with a large vertical bar to the right.



This bar shows a representation of your current throttle level. If you push the joystick forward it will beep and engage the forward gear. To increase the throttle speed, keep holding. To accelerate faster, push it farther forward. Let go to maintain this throttle speed. This engages the Cruise Control feature on the Volvo Penta IPS drives.

Unlike a normal throttle lever, the joystick will pop back to center, but otherwise it works exactly like a throttle control. To slow down, pull it backward. To slow down faster, pull it backward more. It will beep when you get to Neutral and go into reverse if you want here. Just like with any throttle control, be careful of anything loose, such as glasses, kids, or dogs as you do this. Your joystick is now a throttle, and you use it exactly like one. To perform a crash stop of the boat, pull the joystick all the way back. This will act just like pulling your throttle lever back rapidly.

You can also control the Cruise Control mode using the joystick instead of the buttons on the throttle control. Tap the joystick forward to increase the RPM by 50, tap it backward to reduce the RPM by 50.

You can use Joystick Driving together with the autopilot as well. Here you can see that we are using route following mode and going approximately 10 knots.


If you engage the throttle levers when Joystick Driving is engaged, the boat will return to Joystick Steering and you need to start over from neutral throttles to engage Joystick Driving again.

Joystick Driving requires a Glass Cockpit display (see the image above) installed at the helm station you are driving from. In other words,  you cannot use it at a cockpit docking station that only has the smaller 4” or 7” displays installed, such as the one on the Ranger Tug R-43. This is unfortunate as it would be a perfect function to use when trolling for fish. 

Verdict

Joystick Driving is our standard way to operate the boat. We do not use the wheel to steer, and we do not use the throttles to set the speed. With Joystick Driving, we have all the control with a single, intuitive instrument. It takes almost no time to learn, and it is very easy to use. It’s more ergonomic, especially considering that Fluid Motion did a great job on where the joystick is positioned. It provides a relaxing and comfortable experience driving the boat that is incredibly easy to get used to. 

Combinations Of These Functions

Some of the functions described above supersede each other, and it is a little unclear how to tell which ones you actually have. To see which ones are installed on any boat, tap the Throttle icon on the Glass Cockpit display and then tap Full Function List.

Here’s a handy reference guide to what you might see:
  • Joystick Steering - Standard feature. All IPS installations have either this or Joystick Driving. This allows you to steer with the joystick up to any speed, but you have to control the throttles the same way you do on any boat. 
  • Joystick Docking - Standard feature. Low speed driving feature that allows you to control throttle and steering with the joystick. When you let go of the joystick the throttle goes back to neutral, but the boat will keep gliding as long as it has momentum the same way any boat does when you put the throttles in neutral. 
  • DPS - Optional feature. Holds the boat in position, compensating for wind and current. You can move it manually using the joystick but when you let go of the joystick it stops moving and holds in the new position. If you tap the joystick it  moves three feet in that direction and stops  Think of this as a virtual anchor. Requires a special GPS antenna. 
  • Assisted Docking - Optional add-on to DPS. It subsumes the standard DPS mode, so if you have Assisted Docking, you do not have a separate DPS mode. Works exactly like DPS but when you tap the joystick it only moves 1.5 feet. Also includes a side push feature to hold you against a dock. 
  • Joystick Driving - Optional add-on. Works like Joystick Steering but you also control the throttle with the joystick, in addition to steering. Also works up to any speed. Unlike Joystick Docking Joystick Driving engages the cruise control feature, which means you set the RPM with the joystick and then it stays there when you let go of the joystick.  
Which ones you have depends on the options selected when the boat was built, and which features the factory offers. Joystick Driving is a software-only add-on. You can add that to an existing boat. Assisted Docking and DPS depend on the DPS antenna. It can be added, but if you do not have the antenna installed that has to be added as well. If you already have the DPS antenna but not Assisted Docking then Assisted Docking can be added as a software add-on.

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