A Guide to Voice Technology in Warehousing

Voice Technology and Voice Directed Order Picking deliver a whole new level of efficiency for today's modern warehouse.

 - Frequently Asked Questions -

How is Voice Technology used in Warehouse Management?

What can I use it for?

The most common application is Order Picking where improved accuracy and productivity offer a fast payback, but you can also use it for Goods Receiving, Pallet Put-away and Let-down, and Stock Checking. Perpetual Inventory checking can be combined with other tasks.

What equipment do I need?

Each worker needs a belt-worn, wireless terminal with real-time radio communication to the WMS. You will need an 802.11 compliant radio frequency (RF) network and a communications server on the network.

Can I use my existing RF network?

Provided your network is 802.11 compliant, it is likely you can use the existing network. It will be necessary to conduct an RF survey to check RF coverage because the radio reception of a belt worn unit can differ from that of hand held or truck mounted terminals.

What are accuracy improvements can I expect?

Improvements in order picking accuracy are dramatic, and accuracy of 99.9% (one error per thousand picks), and often much better, is usually achieved. The improvements that you obtain will depend on your current method of order picking, but if you are moving from a paper-based system to voice directed picking, picking errors are usually reduced by between 80% and 90%.

What productivity gains can I expect?

Order picking productivity usually improves by 10% to 20% because the hands free and eyes free operation speeds up picking, and trips back to the assignment desk are eliminated. Administrative productivity is improved by paperless picking because the work of printing and distributing picking lists or labels is eliminated, as is the task of keying in picking confirmations, picking amendments and catchweights.

What other benefits will I get?

Eliminating paper picking labels brings a significant cost saving in the cost of the paper alone.

The real time radio communication enables real time stock updating. This in turn allows the triggering of letdowns to replenish picking faces, optimising the use of fork lift trucks and preventing re-picks or waiting time due to empty picking faces. Cycle counting can built in to the replenishment (letdown) task, improving the efficiency of the stock checking process. The improved accuracy of stock recording leads to improved service level, less time spent investigating stock discrepancies and better management of the warehouse.

Safety is improved as the hands free and eyes free operation leads to fewer accidents. Eliminating paper also leads to less waste paper or label backing sheets, resulting in a cleaner, tidier and safer warehouse.

The training time for new pickers is reduced by the use of voice, as a voice directed task is easier to learn than interpreting a paper task. Training time can often be reduced by as much as half.

What is the payback?

If you operate more than one picking shift then the costs are shared across picking shifts and payback can be achieved in as little as 6 months. If you operate a single picking shift, then a payback of one year is more realistic.

Is it possible to calculate my expected Return on Investment (ROI)?

Yes, the white paper "Voice Directed Picking: Expected ROI" covers this in detail. Alternatively, BCP provide an online payback calculator for voice directed picking 

Can I use it in the freezer?

Yes, voice technology is ideal for use in the freezer, and the hands free operation offers even greater productivity improvements as gloves hamper the use of paper or radio data terminals. For exampe, Talkman terminals operate in temperatures down to minus 30°C

Does it work in a noisy environment?

Yes, provided you use voice terminals specifically designed for noisy warehouses and industrial environments.

What’s the difference between speaker dependent and speaker independent voice recognition?

Speaker-dependent systems require each user to “train” the system for his or her individual speech pattern, dialect, or language. Voice training usually takes only a few minutes per user. Training allows the system to be much more accurate and robust in an industrial environment where there is a wide range of accents, dialects, and languages, and much extraneous noise.

Speaker independent technology is designed to match the speaker's voice to previously created, generic voice patterns, and is less suitable for the warehouse environment.

Does each user just have to do the voice training once?

It is often sufficient for a user to perform the voice training just once, and it takes only a few minutes. However, during voice training users do not always speak as they normally would when out in the warehouse, and retraining may be necessary.

Can it handle different dialects and accents?

Yes, each user trains the system for their own voice allowing the speech recognition technology to accurately recognize any user’s speech regardless of accent or dialect. A user can even train the system to recognise responses in a different language.

Does each worker need his own unit?

You need enough units to cover the number of workers on the biggest shift, plus a small percentage of spares. However, users usually have their own individual belts and headsets

How often do the batteries need charging?

The time a voice terminal can operate on a single battery charge depends on a number of factors. The amount of power consumed by the radio card varies significantly between different radio cards, the cold temperatures in a freezer reduce battery life, and the amount of radio communication needed by the application also affect power consumption.

Are the units robust?

Yes, the specialised terminals are designed for warehouse use.

How much does the unit weigh?

A voice terminal weighs around a pound.

How easy is it for workers to get used to it?

Most workers are enthusiastic and get used to it very quickly. It is usually quicker to train a new order picker in voice directed picking than paper-based picking.

Can I use it if I have a cold?

The speech recognition is not usually affected by a cold, but hoarseness or laryngitis may affect operation. Voice retraining can be done if you experience problems.

Can hearing impaired people use it?

As long as the users are not 100% hearing impaired, they can often use the system.

What happens if a user is out of range of an RF access point?

Some voice terminals have onboard intelligence and can continue to operate out of RF coverage, but the functions available will depend on the application. Others need 100% coverage to operate.

How does a picker confirm what he has picked?

The picker will normally read back the last 2 or 3 digits of the barcode so that the system can check the correct item has been picked. The picker does not have to read back the entire barcode.

Is the voice transmitted over the RF network?

With most systems, speech synthesis and recognition is carried out on the unit, and only data is transmitted over the RF network. With systems that transmit voice over the network, the bandwidth restricts the number of users and high performance voice servers are required. If you will have a significant number of users, it is important to choose a system without these limitations.