If you want to know how well soldiers like all their new technological toys, ask a sergeant major.The organizers of this week's Army Science Conference in Orlando, Fla., put the question to five command sergeant majors: Hector Marin of the Research, Development and Engineering Command (RDECOM); Philip Johndrow of the Combined Arms Center; Jeffrey Mellinger of the Army Materiel Command; Robert Moore of the Army's National Training Center; and James Diggs of the North Atlantic Regional Medical Command. Each has advanced to the most senior noncommissioned officer rank short of the sergeant major of the Army. Each also plays the traditional role of representing the interests of the enlisted men back up the chain of command.At the conference, they were asked to talk about technological advances and the drawbacks of new equipment, particularly in the wars in Iraq and Afghanistan.For the most part, they had few complaints that new gear deployed to the field was unnecessary or inappropriate, although Marin said, 'we have gotten a lot of toys, so there may be some redundancy.'However, the biggest concern he has is with the weight of the equipment, particularly all the batteries needed to power devices such as radios, helmet-mounted displays, Global Positioning System devices and tactical computers. A soldier can end up lugging a rucksack that weighs as much as 70 pounds, Marin said. A typical platoon leader carries 34 batteries of eight different types, 'and as you go down in rank, the amount of weight goes up,' he said. 'Batteries can wind up being as much as 25 percent of a soldier's load, which is quite a lot.'The variety of batteries also creates logistical problems, he said. So his plea to those designing new gadgets is to 'use an existing battery, or if you're going to develop a new battery, give us one battery that replaces nine other batteries.'Marin said RDECOM is making progress in developing new batteries that weigh less and last longer, some of which are based on zinc-air cells. Solar battery rechargers also hold the promise of allowing the Army to reduce waste and the amount of spares a soldier must carry.Marin also showed a video about a robotic exoskeleton that a soldier could wear to lift and carry much greater weight without fatigue. If that technology makes it to the field, the soldier of the future might look a lot like Iron Man. 'We're moving toward that next-generation, F-16-on-legs concept,' Marin said.Mellinger said he, too, is concerned that soldiers are being overloaded. Of course, some of what weighs them down, such as personal armor, also saves lives. As a soldier, he said he's glad to have the new equipment, 'but at some point, my knees are going to buckle without that exoskeleton.''The old saying of 'too light to fight and too heavy to run' has never been more true,' Mellinger added. Although the weight might generate complaints, it's not stopping soldiers from getting the job done. 'It is physically demanding,' he said. 'And it's getting more and more difficult to move about, as opposed to someone just running and carrying a weapon. But it also gives the soldiers a lot of confidence in their ability to fight and survive.'Commanders have the discretion to let their soldiers shed unnecessary equipment if heat or weariness outweighs whatever benefits it has to offer.The Army Materiel Command is responsible for equipping soldiers and maintaining that equipment. However, soldiers and their commanders sometimes work around official procurement rules to bring commercial technology to the field, and those tools need to graduate to program-of-record status so the command can support and maintain them properly, Mellinger said.He added that the command has been working with soldiers to devise better ways of armoring their vehicles and otherwise countering the threat from improvised explosive devices, but that progress is often temporary. 'We have to know that every technology we can create will be countered very quickly, with our adversaries coming up with ways not to defeat our systems but to go around them,' he said.Johndrow talked about advances in protective armor for soldiers and their vehicles. Personal armor has gotten lighter and more flexible, and the addition of mesh lining makes it a little cooler to wear, he said.Vehicle protection has also improved significantly, but the speed of those advances has sometimes created its own problems. For example, Army Hummers have evolved from open vehicles with little armor in which a gunner would sit highly exposed on a raised seat to being much more enclosed, with a protective turret for the gunner. The protection offered to soldiers is improving further with the new Common Remotely Operated Weapon Station, a robotic gun turret a soldier can operate from within the vehicle.However, when the redesigned Hummers were delivered to the field, they turned out to be top heavy, resulting in more rollover accidents. So drivers who had learned the maxim that 'speed is safety' needed to be retrained to slow down if they were to benefit from the increased protection, Johndrow said.Similarly, the new, more heavily armored mine-resistant, ambush-protected vehicles were rushed through design and production and out into the field so quickly that the first time drivers were trained in their use was in Iraq. Although that caused some problems, it was a boon for soldiers' morale, Johndrow said.'It let them know how much everyone in the world cared about them that we were working so hard to get this vehicle out there as fast as possible,' he said.